sfrench/cifs-2.6.git
2 years agoMerge tag 'fscache-next-20180406' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Sat, 7 Apr 2018 16:08:24 +0000 (09:08 -0700)]
Merge tag 'fscache-next-20180406' of git://git./linux/kernel/git/dhowells/linux-fs

Pull fscache updates from David Howells:
 "Three patches that fix some of AFS's usage of fscache:

   (1) Need to invalidate the cache if a foreign data change is detected
       on the server.

   (2) Move the vnode ID uniquifier (equivalent to i_generation) from
       the auxiliary data to the index key to prevent a race between
       file delete and a subsequent file create seeing the same index
       key.

   (3) Need to retire cookies that correspond to files that we think got
       deleted on the server.

  Four patches to fix some things in fscache and cachefiles:

   (4) Fix a couple of checker warnings.

   (5) Correctly indicate to the end-of-operation callback whether an
       operation completed or was cancelled.

   (6) Add a check for multiple cookie relinquishment.

   (7) Fix a path through the asynchronous write that doesn't wake up a
       waiter for a page if the cache decides not to write that page,
       but discards it instead.

  A couple of patches to add tracepoints to fscache and cachefiles:

   (8) Add tracepoints for cookie operators, object state machine
       execution, cachefiles object management and cachefiles VFS
       operations.

   (9) Add tracepoints for fscache operation management and page
       wrangling.

  And then three development patches:

  (10) Attach the index key and auxiliary data to the cookie, pass this
       information through various fscache-netfs API functions and get
       rid of the callbacks to the netfs to get it.

       This means that the cache can get at this information, even if
       the netfs goes away. It also means that the cache can be lazy in
       updating the coherency data.

  (11) Pass the object data size through various fscache-netfs API
       rather than calling back to the netfs for it, and store the value
       in the object.

       This makes it easier to correctly resize the object, as the size
       is updated on writes to the cache, rather than calling back out
       to the netfs.

  (12) Maintain a catalogue of allocated cookies. This makes it possible
       to catch cookie collision up front rather than down in the bowels
       of the cache being run from a service thread from the object
       state machine.

       This will also make it possible in the future to reconnect to a
       cookie that's not gone dead yet because it's waiting for
       finalisation of the storage and also make it possible to bring
       cookies online if the cache is added after the cookie has been
       obtained"

* tag 'fscache-next-20180406' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  fscache: Maintain a catalogue of allocated cookies
  fscache: Pass object size in rather than calling back for it
  fscache: Attach the index key and aux data to the cookie
  fscache: Add more tracepoints
  fscache: Add tracepoints
  fscache: Fix hanging wait on page discarded by writeback
  fscache: Detect multiple relinquishment of a cookie
  fscache: Pass the correct cancelled indications to fscache_op_complete()
  fscache, cachefiles: Fix checker warnings
  afs: Be more aggressive in retiring cached vnodes
  afs: Use the vnode ID uniquifier in the cache key not the aux data
  afs: Invalidate cache on server data change

2 years agoMerge tag 'vfio-v4.17-rc1' of git://github.com/awilliam/linux-vfio
Linus Torvalds [Sat, 7 Apr 2018 02:44:27 +0000 (19:44 -0700)]
Merge tag 'vfio-v4.17-rc1' of git://github.com/awilliam/linux-vfio

Pull VFIO updates from Alex Williamson:

 - Adopt iommu_unmap_fast() interface to type1 backend
   (Suravee Suthikulpanit)

 - mdev sample driver fixup (Shunyong Yang)

 - More efficient PFN mapping handling in type1 backend
   (Jason Cai)

 - VFIO device ioeventfd interface (Alex Williamson)

 - Tag new vfio-platform sub-maintainer (Alex Williamson)

* tag 'vfio-v4.17-rc1' of git://github.com/awilliam/linux-vfio:
  MAINTAINERS: vfio/platform: Update sub-maintainer
  vfio/pci: Add ioeventfd support
  vfio/pci: Use endian neutral helpers
  vfio/pci: Pull BAR mapping setup from read-write path
  vfio/type1: Improve memory pinning process for raw PFN mapping
  vfio-mdev/samples: change RDI interrupt condition
  vfio/type1: Adopt fast IOTLB flush interface when unmap IOVAs

2 years agoMerge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
Linus Torvalds [Sat, 7 Apr 2018 02:21:41 +0000 (19:21 -0700)]
Merge tag 'for_linus' of git://git./linux/kernel/git/mst/vhost

Pull fw_cfg, vhost updates from Michael Tsirkin:
 "This cleans up the qemu fw cfg device driver.

  On top of this, vmcore is dumped there on crash to help debugging
  with kASLR enabled.

  Also included are some fixes in vhost"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  vhost: add vsock compat ioctl
  vhost: fix vhost ioctl signature to build with clang
  fw_cfg: write vmcoreinfo details
  crash: export paddr_vmcoreinfo_note()
  fw_cfg: add DMA register
  fw_cfg: add a public uapi header
  fw_cfg: handle fw_cfg_read_blob() error
  fw_cfg: remove inline from fw_cfg_read_blob()
  fw_cfg: fix sparse warnings around FW_CFG_FILE_DIR read
  fw_cfg: fix sparse warning reading FW_CFG_ID
  fw_cfg: fix sparse warnings with fw_cfg_file
  fw_cfg: fix sparse warnings in fw_cfg_sel_endianness()
  ptr_ring: fix build

2 years agoMerge tag 'pci-v4.17-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaa...
Linus Torvalds [Sat, 7 Apr 2018 01:31:06 +0000 (18:31 -0700)]
Merge tag 'pci-v4.17-changes' of git://git./linux/kernel/git/helgaas/pci

Pull PCI updates from Bjorn Helgaas:

 - move pci_uevent_ers() out of pci.h (Michael Ellerman)

 - skip ASPM common clock warning if BIOS already configured it (Sinan
   Kaya)

 - fix ASPM Coverity warning about threshold_ns (Gustavo A. R. Silva)

 - remove last user of pci_get_bus_and_slot() and the function itself
   (Sinan Kaya)

 - add decoding for 16 GT/s link speed (Jay Fang)

 - add interfaces to get max link speed and width (Tal Gilboa)

 - add pcie_bandwidth_capable() to compute max supported link bandwidth
   (Tal Gilboa)

 - add pcie_bandwidth_available() to compute bandwidth available to
   device (Tal Gilboa)

 - add pcie_print_link_status() to log link speed and whether it's
   limited (Tal Gilboa)

 - use PCI core interfaces to report when device performance may be
   limited by its slot instead of doing it in each driver (Tal Gilboa)

 - fix possible cpqphp NULL pointer dereference (Shawn Lin)

 - rescan more of the hierarchy on ACPI hotplug to fix Thunderbolt/xHCI
   hotplug (Mika Westerberg)

 - add support for PCI I/O port space that's neither directly accessible
   via CPU in/out instructions nor directly mapped into CPU physical
   memory space. This is fairly intrusive and includes minor changes to
   interfaces used for I/O space on most platforms (Zhichang Yuan, John
   Garry)

 - add support for HiSilicon Hip06/Hip07 LPC I/O space (Zhichang Yuan,
   John Garry)

 - use PCI_EXP_DEVCTL2_COMP_TIMEOUT in rapidio/tsi721 (Bjorn Helgaas)

 - remove possible NULL pointer dereference in of_pci_bus_find_domain_nr()
   (Shawn Lin)

 - report quirk timings with dev_info (Bjorn Helgaas)

 - report quirks that take longer than 10ms (Bjorn Helgaas)

 - add and use Altera Vendor ID (Johannes Thumshirn)

 - tidy Makefiles and comments (Bjorn Helgaas)

 - don't set up INTx if MSI or MSI-X is enabled to align cris, frv,
   ia64, and mn10300 with x86 (Bjorn Helgaas)

 - move pcieport_if.h to drivers/pci/pcie/ to encapsulate it (Frederick
   Lawler)

 - merge pcieport_if.h into portdrv.h (Bjorn Helgaas)

 - move workaround for BIOS PME issue from portdrv to PCI core (Bjorn
   Helgaas)

 - completely disable portdrv with "pcie_ports=compat" (Bjorn Helgaas)

 - remove portdrv link order dependency (Bjorn Helgaas)

 - remove support for unused VC portdrv service (Bjorn Helgaas)

 - simplify portdrv feature permission checking (Bjorn Helgaas)

 - remove "pcie_hp=nomsi" parameter (use "pci=nomsi" instead) (Bjorn
   Helgaas)

 - remove unnecessary "pcie_ports=auto" parameter (Bjorn Helgaas)

 - use cached AER capability offset (Frederick Lawler)

 - don't enable DPC if BIOS hasn't granted AER control (Mika Westerberg)

 - rename pcie-dpc.c to dpc.c (Bjorn Helgaas)

 - use generic pci_mmap_resource_range() instead of powerpc and xtensa
   arch-specific versions (David Woodhouse)

 - support arbitrary PCI host bridge offsets on sparc (Yinghai Lu)

 - remove System and Video ROM reservations on sparc (Bjorn Helgaas)

 - probe for device reset support during enumeration instead of runtime
   (Bjorn Helgaas)

 - add ACS quirk for Ampere (née APM) root ports (Feng Kan)

 - add function 1 DMA alias quirk for Marvell 88SE9220 (Thomas
   Vincent-Cross)

 - protect device restore with device lock (Sinan Kaya)

 - handle failure of FLR gracefully (Sinan Kaya)

 - handle CRS (config retry status) after device resets (Sinan Kaya)

 - skip various config reads for SR-IOV VFs as an optimization
   (KarimAllah Ahmed)

 - consolidate VPD code in vpd.c (Bjorn Helgaas)

 - add Tegra dependency on PCI_MSI_IRQ_DOMAIN (Arnd Bergmann)

 - add DT support for R-Car r8a7743 (Biju Das)

 - fix a PCI_EJECT vs PCI_BUS_RELATIONS race condition in Hyper-V host
   bridge driver that causes a general protection fault (Dexuan Cui)

 - fix Hyper-V host bridge hang in MSI setup on 1-vCPU VMs with SR-IOV
   (Dexuan Cui)

 - fix Hyper-V host bridge hang when ejecting a VF before setting up MSI
   (Dexuan Cui)

 - make several structures static (Fengguang Wu)

 - increase number of MSI IRQs supported by Synopsys DesignWare bridges
   from 32 to 256 (Gustavo Pimentel)

 - implemented multiplexed IRQ domain API and remove obsolete MSI IRQ
   API from DesignWare drivers (Gustavo Pimentel)

 - add Tegra power management support (Manikanta Maddireddy)

 - add Tegra loadable module support (Manikanta Maddireddy)

 - handle 64-bit BARs correctly in endpoint support (Niklas Cassel)

 - support optional regulator for HiSilicon STB (Shawn Guo)

 - use regulator bulk API for Qualcomm apq8064 (Srinivas Kandagatla)

 - support power supplies for Qualcomm msm8996 (Srinivas Kandagatla)

* tag 'pci-v4.17-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (123 commits)
  MAINTAINERS: Add John Garry as maintainer for HiSilicon LPC driver
  HISI LPC: Add ACPI support
  ACPI / scan: Do not enumerate Indirect IO host children
  ACPI / scan: Rename acpi_is_serial_bus_slave() for more general use
  HISI LPC: Support the LPC host on Hip06/Hip07 with DT bindings
  of: Add missing I/O range exception for indirect-IO devices
  PCI: Apply the new generic I/O management on PCI IO hosts
  PCI: Add fwnode handler as input param of pci_register_io_range()
  PCI: Remove __weak tag from pci_register_io_range()
  MAINTAINERS: Add missing /drivers/pci/cadence directory entry
  fm10k: Report PCIe link properties with pcie_print_link_status()
  net/mlx5e: Use pcie_bandwidth_available() to compute bandwidth
  net/mlx5: Report PCIe link properties with pcie_print_link_status()
  net/mlx4_core: Report PCIe link properties with pcie_print_link_status()
  PCI: Add pcie_print_link_status() to log link speed and whether it's limited
  PCI: Add pcie_bandwidth_available() to compute bandwidth available to device
  misc: pci_endpoint_test: Handle 64-bit BARs properly
  PCI: designware-ep: Make dw_pcie_ep_reset_bar() handle 64-bit BARs properly
  PCI: endpoint: Make sure that BAR_5 does not have 64-bit flag set when clearing
  PCI: endpoint: Make epc->ops->clear_bar()/pci_epc_clear_bar() take struct *epf_bar
  ...

2 years agoMerge tag 'for-linus-unmerged' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma...
Linus Torvalds [Sat, 7 Apr 2018 00:35:43 +0000 (17:35 -0700)]
Merge tag 'for-linus-unmerged' of git://git./linux/kernel/git/rdma/rdma

Pull rdma updates from Jason Gunthorpe:
 "Doug and I are at a conference next week so if another PR is sent I
  expect it to only be bug fixes. Parav noted yesterday that there are
  some fringe case behavior changes in his work that he would like to
  fix, and I see that Intel has a number of rc looking patches for HFI1
  they posted yesterday.

  Parav is again the biggest contributor by patch count with his ongoing
  work to enable container support in the RDMA stack, followed by Leon
  doing syzkaller inspired cleanups, though most of the actual fixing
  went to RC.

  There is one uncomfortable series here fixing the user ABI to actually
  work as intended in 32 bit mode. There are lots of notes in the commit
  messages, but the basic summary is we don't think there is an actual
  32 bit kernel user of drivers/infiniband for several good reasons.

  However we are seeing people want to use a 32 bit user space with 64
  bit kernel, which didn't completely work today. So in fixing it we
  required a 32 bit rxe user to upgrade their userspace. rxe users are
  still already quite rare and we think a 32 bit one is non-existing.

   - Fix RDMA uapi headers to actually compile in userspace and be more
     complete

   - Three shared with netdev pull requests from Mellanox:

      * 7 patches, mostly to net with 1 IB related one at the back).
        This series addresses an IRQ performance issue (patch 1),
        cleanups related to the fix for the IRQ performance problem
        (patches 2-6), and then extends the fragmented completion queue
        support that already exists in the net side of the driver to the
        ib side of the driver (patch 7).

      * Mostly IB, with 5 patches to net that are needed to support the
        remaining 10 patches to the IB subsystem. This series extends
        the current 'representor' framework when the mlx5 driver is in
        switchdev mode from being a netdev only construct to being a
        netdev/IB dev construct. The IB dev is limited to raw Eth queue
        pairs only, but by having an IB dev of this type attached to the
        representor for a switchdev port, it enables DPDK to work on the
        switchdev device.

      * All net related, but needed as infrastructure for the rdma
        driver

   - Updates for the hns, i40iw, bnxt_re, cxgb3, cxgb4, hns drivers

   - SRP performance updates

   - IB uverbs write path cleanup patch series from Leon

   - Add RDMA_CM support to ib_srpt. This is disabled by default. Users
     need to set the port for ib_srpt to listen on in configfs in order
     for it to be enabled
     (/sys/kernel/config/target/srpt/discovery_auth/rdma_cm_port)

   - TSO and Scatter FCS support in mlx4

   - Refactor of modify_qp routine to resolve problems seen while
     working on new code that is forthcoming

   - More refactoring and updates of RDMA CM for containers support from
     Parav

   - mlx5 'fine grained packet pacing', 'ipsec offload' and 'device
     memory' user API features

   - Infrastructure updates for the new IOCTL interface, based on
     increased usage

   - ABI compatibility bug fixes to fully support 32 bit userspace on 64
     bit kernel as was originally intended. See the commit messages for
     extensive details

   - Syzkaller bugs and code cleanups motivated by them"

* tag 'for-linus-unmerged' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (199 commits)
  IB/rxe: Fix for oops in rxe_register_device on ppc64le arch
  IB/mlx5: Device memory mr registration support
  net/mlx5: Mkey creation command adjustments
  IB/mlx5: Device memory support in mlx5_ib
  net/mlx5: Query device memory capabilities
  IB/uverbs: Add device memory registration ioctl support
  IB/uverbs: Add alloc/free dm uverbs ioctl support
  IB/uverbs: Add device memory capabilities reporting
  IB/uverbs: Expose device memory capabilities to user
  RDMA/qedr: Fix wmb usage in qedr
  IB/rxe: Removed GID add/del dummy routines
  RDMA/qedr: Zero stack memory before copying to user space
  IB/mlx5: Add ability to hash by IPSEC_SPI when creating a TIR
  IB/mlx5: Add information for querying IPsec capabilities
  IB/mlx5: Add IPsec support for egress and ingress
  {net,IB}/mlx5: Add ipsec helper
  IB/mlx5: Add modify_flow_action_esp verb
  IB/mlx5: Add implementation for create and destroy action_xfrm
  IB/uverbs: Introduce ESP steering match filter
  IB/uverbs: Add modify ESP flow_action
  ...

2 years agoMerge tag 'mailbox-v4.17' of git://git.linaro.org/landing-teams/working/fujitsu/integ...
Linus Torvalds [Sat, 7 Apr 2018 00:20:14 +0000 (17:20 -0700)]
Merge tag 'mailbox-v4.17' of git://git.linaro.org/landing-teams/working/fujitsu/integration

Pull mailbox updates from Jassi Brar:

 - New Hi3660 mailbox driver

 - Fix TEGRA Kconfig warning

 - Broadcom: use dma_pool_zalloc instead of dma_pool_alloc+memset

* tag 'mailbox-v4.17' of git://git.linaro.org/landing-teams/working/fujitsu/integration:
  mailbox: Add support for Hi3660 mailbox
  dt-bindings: mailbox: Introduce Hi3660 controller binding
  mailbox: tegra: relax TEGRA_HSP_MBOX Kconfig dependencies
  maillbox: bcm-flexrm-mailbox: Use dma_pool_zalloc()

2 years agoMerge tag 'selinux-pr-20180403' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Fri, 6 Apr 2018 22:39:26 +0000 (15:39 -0700)]
Merge tag 'selinux-pr-20180403' of git://git./linux/kernel/git/pcmoore/selinux

Pull SELinux updates from Paul Moore:
 "A bigger than usual pull request for SELinux, 13 patches (lucky!)
  along with a scary looking diffstat.

  Although if you look a bit closer, excluding the usual minor
  tweaks/fixes, there are really only two significant changes in this
  pull request: the addition of proper SELinux access controls for SCTP
  and the encapsulation of a lot of internal SELinux state.

  The SCTP changes are the result of a multi-month effort (maybe even a
  year or longer?) between the SELinux folks and the SCTP folks to add
  proper SELinux controls. A special thanks go to Richard for seeing
  this through and keeping the effort moving forward.

  The state encapsulation work is a bit of janitorial work that came out
  of some early work on SELinux namespacing. The question of namespacing
  is still an open one, but I believe there is some real value in the
  encapsulation work so we've split that out and are now sending that up
  to you"

* tag 'selinux-pr-20180403' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
  selinux: wrap AVC state
  selinux: wrap selinuxfs state
  selinux: fix handling of uninitialized selinux state in get_bools/classes
  selinux: Update SELinux SCTP documentation
  selinux: Fix ltp test connect-syscall failure
  selinux: rename the {is,set}_enforcing() functions
  selinux: wrap global selinux state
  selinux: fix typo in selinux_netlbl_sctp_sk_clone declaration
  selinux: Add SCTP support
  sctp: Add LSM hooks
  sctp: Add ip option support
  security: Add support for SCTP security hooks
  netlabel: If PF_INET6, check sk_buff ip header version

2 years agoMerge tag 'audit-pr-20180403' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoor...
Linus Torvalds [Fri, 6 Apr 2018 22:01:25 +0000 (15:01 -0700)]
Merge tag 'audit-pr-20180403' of git://git./linux/kernel/git/pcmoore/audit

Pull audit updates from Paul Moore:
 "We didn't have anything to send for v4.16, but we're back with a
  little more than usual for v4.17.

  Eleven patches in total, most fall into the small fix category, but
  there are three non-trivial changes worth calling out:

   - the audit entry filter is being removed after deprecating it for
     quite a while (years of no one really using it because it turns out
     to be not very practical)

   - created our own version of "__mutex_owner()" because the locking
     folks were upset we were using theirs

   - improved our handling of kernel command line parameters to make
     them more forgiving

   - we fixed auditing of symlink operations

  Everything passes the audit-testsuite and as of a few minutes ago it
  merges well with your tree"

* tag 'audit-pr-20180403' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
  audit: add refused symlink to audit_names
  audit: remove path param from link denied function
  audit: link denied should not directly generate PATH record
  audit: make ANOM_LINK obey audit_enabled and audit_dummy_context
  audit: do not panic on invalid boot parameter
  audit: track the owner of the command mutex ourselves
  audit: return on memory error to avoid null pointer dereference
  audit: bail before bug check if audit disabled
  audit: deprecate the AUDIT_FILTER_ENTRY filter
  audit: session ID should not set arch quick field pointer
  audit: update bugtracker and source URIs

2 years agoMerge tag 'pstore-v4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees...
Linus Torvalds [Fri, 6 Apr 2018 21:59:01 +0000 (14:59 -0700)]
Merge tag 'pstore-v4.17-rc1' of git://git./linux/kernel/git/kees/linux

Pull pstore updates from Kees Cook:
 "This cycle was almost entirely improvements to the pstore compression
  options, noted below:

   - Add lz4hc and 842 to pstore compression options (Geliang Tang)

   - Refactor to use crypto compression API (Geliang Tang)

   - Fix up Kconfig dependencies for compression (Arnd Bergmann)

   - Allow for run-time compression selection

   - Remove stack VLA usage"

* tag 'pstore-v4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  pstore: fix crypto dependencies
  pstore: Use crypto compress API
  pstore/ram: Do not use stack VLA for parity workspace
  pstore: Select compression at runtime
  pstore: Avoid size casts for 842 compression
  pstore: Add lz4hc and 842 compression support

2 years agoMerge branch 'akpm' (patches from Andrew)
Linus Torvalds [Fri, 6 Apr 2018 21:19:26 +0000 (14:19 -0700)]
Merge branch 'akpm' (patches from Andrew)

Merge updates from Andrew Morton:

 - a few misc things

 - ocfs2 updates

 - the v9fs maintainers have been missing for a long time. I've taken
   over v9fs patch slinging.

 - most of MM

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (116 commits)
  mm,oom_reaper: check for MMF_OOM_SKIP before complaining
  mm/ksm: fix interaction with THP
  mm/memblock.c: cast constant ULLONG_MAX to phys_addr_t
  headers: untangle kmemleak.h from mm.h
  include/linux/mmdebug.h: make VM_WARN* non-rvals
  mm/page_isolation.c: make start_isolate_page_range() fail if already isolated
  mm: change return type to vm_fault_t
  mm, oom: remove 3% bonus for CAP_SYS_ADMIN processes
  mm, page_alloc: wakeup kcompactd even if kswapd cannot free more memory
  kernel/fork.c: detect early free of a live mm
  mm: make counting of list_lru_one::nr_items lockless
  mm/swap_state.c: make bool enable_vma_readahead and swap_vma_readahead() static
  block_invalidatepage(): only release page if the full page was invalidated
  mm: kernel-doc: add missing parameter descriptions
  mm/swap.c: remove @cold parameter description for release_pages()
  mm/nommu: remove description of alloc_vm_area
  zram: drop max_zpage_size and use zs_huge_class_size()
  zsmalloc: introduce zs_huge_class_size()
  mm: fix races between swapoff and flush dcache
  fs/direct-io.c: minor cleanups in do_blockdev_direct_IO
  ...

2 years agoMerge tag 'mtd/for-4.17' of git://git.infradead.org/linux-mtd
Linus Torvalds [Fri, 6 Apr 2018 19:15:41 +0000 (12:15 -0700)]
Merge tag 'mtd/for-4.17' of git://git.infradead.org/linux-mtd

Pull MTD updates from Boris Brezillon:
 "MTD Core:
   - Remove support for asynchronous erase (not implemented by any of
     the existing drivers anyway)
   - Remove Cyrille from the list of SPI NOR and MTD maintainers
   - Fix kernel doc headers
   - Allow users to define the partitions parsers they want to test
     through a DT property (compatible of the partitions subnode)
   - Remove the bfin-async-flash driver (the only architecture using it
     has been removed)
   - Fix pagetest test
   - Add extra checks in mtd_erase()
   - Simplify the MTD partition creation logic and get rid of
     mtd_add_device_partitions()

  MTD Drivers:
   - Add endianness information to the physmap DT binding
   - Add Eon EN29LV400A IDs to JEDEC probe logic
   - Use %*ph where appropriate

  SPI NOR Drivers:
   - Make fsl-quaspi assign different names to MTD devices connected to
     the same QSPI controller
   - Remove an unneeded driver.bus assigned in the fsl-qspi driver

  NAND Core:
   - Prepare arrival of the SPI NAND subsystem by implementing a generic
     (interface-agnostic) layer to ease manipulation of NAND devices
   - Move onenand code base to the drivers/mtd/nand/ dir
   - Rework timing mode selection
   - Provide a generic way for NAND chip drivers to flag a specific
     GET/SET FEATURE operation as supported/unsupported
   - Stop embedding ONFI/JEDEC param page in nand_chip

  NAND Drivers:
   - Rework/cleanup of the mxc driver
   - Various cleanups in the vf610 driver
   - Migrate the fsmc and vf610 to ->exec_op()
   - Get rid of the pxa driver (replaced by marvell_nand)
   - Support ->setup_data_interface() in the GPMI driver
   - Fix probe error path in several drivers
   - Remove support for unused hw_syndrome mode in sunxi_nand
   - Various minor improvements"

* tag 'mtd/for-4.17' of git://git.infradead.org/linux-mtd: (89 commits)
  dt-bindings: fsl-quadspi: Add the example of two SPI NOR
  mtd: fsl-quadspi: Distinguish the mtd device names
  mtd: nand: Fix some function description mismatches in core.c
  mtd: fsl-quadspi: Remove unneeded driver.bus assignment
  mtd: rawnand: marvell: Rename ->ecc_clk into ->core_clk
  mtd: rawnand: s3c2410: enhance the probe function error path
  mtd: rawnand: tango: fix probe function error path
  mtd: rawnand: sh_flctl: fix the probe function error path
  mtd: rawnand: omap2: fix the probe function error path
  mtd: rawnand: mxc: fix probe function error path
  mtd: rawnand: denali: fix probe function error path
  mtd: rawnand: davinci: fix probe function error path
  mtd: rawnand: cafe: fix probe function error path
  mtd: rawnand: brcmnand: fix probe function error path
  mtd: rawnand: sunxi: Stop supporting ECC_HW_SYNDROME mode
  mtd: rawnand: marvell: Fix clock resource by adding a register clock
  mtd: ftl: Use DIV_ROUND_UP()
  mtd: Fix some function description mismatches in mtdcore.c
  mtd: physmap_of: update struct map_info's swap as per map requirement
  dt-bindings: mtd-physmap: Add endianness supports
  ...

2 years agoMerge tag 'for-4.17/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Fri, 6 Apr 2018 18:50:19 +0000 (11:50 -0700)]
Merge tag 'for-4.17/dm-changes' of git://git./linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - DM core passthrough ioctl fix to retain reference to DM table, and
   that table's block devices, while issuing the ioctl to one of those
   block devices.

 - DM core passthrough ioctl fix to _not_ override the fmode_t used to
   issue the ioctl. Overriding by using the fmode_t that the block
   device was originally open with during DM table load is a liability.

 - Add DM core support for secure erase forwarding and update the DM
   linear and DM striped targets to support them.

 - A DM core 4.16 stable fix to allow abnormal IO (e.g. discard, write
   same, write zeroes) for targets that make use of the non-splitting IO
   variant (as is done for multipath or thinp when layered directly on
   NVMe).

 - Allow DM targets to return a payload in response to a DM message that
   they are sent. This is useful for DM targets that would like to
   provide statistics data in response to DM messages.

 - Update DM bufio to support non-power-of-2 block sizes. Numerous other
   related changes prepare the DM bufio code for this support.

 - Fix DM crypt to use a bounded amount of memory across the entire
   system. This is to avoid OOM that can otherwise occur in response to
   certain pathological IO workloads (e.g. discarding a large DM crypt
   device).

 - Add a 'check_at_most_once' feature to the DM verity target to allow
   verity to be used on mobile devices that have very limited resources.

 - Fix the DM integrity target to fail early if a keyed algorithm (e.g.
   HMAC) is to be used but the key isn't set.

 - Add non-power-of-2 support to the DM unstripe target.

 - Eliminate the use of a Variable Length Array in the DM stripe target.

 - Update the DM log-writes target to record metadata (REQ_META flag).

 - DM raid fixes for its nosync status and some variable range issues.

* tag 'for-4.17/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (28 commits)
  dm: remove fmode_t argument from .prepare_ioctl hook
  dm: hold DM table for duration of ioctl rather than use blkdev_get
  dm raid: fix parse_raid_params() variable range issue
  dm verity: make verity_for_io_block static
  dm verity: add 'check_at_most_once' option to only validate hashes once
  dm bufio: don't embed a bio in the dm_buffer structure
  dm bufio: support non-power-of-two block sizes
  dm bufio: use slab cache for dm_buffer structure allocations
  dm bufio: reorder fields in dm_buffer structure
  dm bufio: relax alignment constraint on slab cache
  dm bufio: remove code that merges slab caches
  dm bufio: get rid of slab cache name allocations
  dm bufio: move dm-bufio.h to include/linux/
  dm bufio: delete outdated comment
  dm: add support for secure erase forwarding
  dm: backfill abnormal IO support to non-splitting IO submission
  dm raid: fix nosync status
  dm mpath: use DM_MAPIO_SUBMITTED instead of magic number 0 in process_queued_bios()
  dm stripe: get rid of a Variable Length Array (VLA)
  dm log writes: record metadata flag for better flags record
  ...

2 years agoMerge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Linus Torvalds [Fri, 6 Apr 2018 18:07:08 +0000 (11:07 -0700)]
Merge branch 'work.misc' of git://git./linux/kernel/git/viro/vfs

Pull misc vfs updates from Al Viro:
 "Assorted stuff, including Christoph's I_DIRTY patches"

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fs: move I_DIRTY_INODE to fs.h
  ubifs: fix bogus __mark_inode_dirty(I_DIRTY_SYNC | I_DIRTY_DATASYNC) call
  ntfs: fix bogus __mark_inode_dirty(I_DIRTY_SYNC | I_DIRTY_DATASYNC) call
  gfs2: fix bogus __mark_inode_dirty(I_DIRTY_SYNC | I_DIRTY_DATASYNC) calls
  fs: fold open_check_o_direct into do_dentry_open
  vfs: Replace stray non-ASCII homoglyph characters with their ASCII equivalents
  vfs: make sure struct filename->iname is word-aligned
  get rid of pointless includes of fs_struct.h
  [poll] annotate SAA6588_CMD_POLL users

2 years agoMerge remote-tracking branch 'lorenzo/pci/cadence' into next
Bjorn Helgaas [Fri, 6 Apr 2018 13:41:08 +0000 (08:41 -0500)]
Merge remote-tracking branch 'lorenzo/pci/cadence' into next

* lorenzo/pci/cadence:
  MAINTAINERS: Add missing /drivers/pci/cadence directory entry

2 years agofscache: Maintain a catalogue of allocated cookies
David Howells [Wed, 4 Apr 2018 12:41:28 +0000 (13:41 +0100)]
fscache: Maintain a catalogue of allocated cookies

Maintain a catalogue of allocated cookies so that cookie collisions can be
handled properly.  For the moment, this just involves printing a warning
and returning a NULL cookie to the caller of fscache_acquire_cookie(), but
in future it might make sense to wait for the old cookie to finish being
cleaned up.

This requires the cookie key to be stored attached to the cookie so that we
still have the key available if the netfs relinquishes the cookie.  This is
done by an earlier patch.

The catalogue also renders redundant fscache_netfs_list (used for checking
for duplicates), so that can be removed.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Anna Schumaker <anna.schumaker@netapp.com>
Tested-by: Steve Dickson <steved@redhat.com>
2 years agofscache: Pass object size in rather than calling back for it
David Howells [Wed, 4 Apr 2018 12:41:28 +0000 (13:41 +0100)]
fscache: Pass object size in rather than calling back for it

Pass the object size in to fscache_acquire_cookie() and
fscache_write_page() rather than the netfs providing a callback by which it
can be received.  This makes it easier to update the size of the object
when a new page is written that extends the object.

The current object size is also passed by fscache to the check_aux
function, obviating the need to store it in the aux data.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Anna Schumaker <anna.schumaker@netapp.com>
Tested-by: Steve Dickson <steved@redhat.com>
2 years agomm,oom_reaper: check for MMF_OOM_SKIP before complaining
Tetsuo Handa [Thu, 5 Apr 2018 23:25:45 +0000 (16:25 -0700)]
mm,oom_reaper: check for MMF_OOM_SKIP before complaining

I got "oom_reaper: unable to reap pid:" messages when the victim thread
was blocked inside free_pgtables() (which occurred after returning from
unmap_vmas() and setting MMF_OOM_SKIP).  We don't need to complain when
exit_mmap() already set MMF_OOM_SKIP.

  Killed process 7558 (a.out) total-vm:4176kB, anon-rss:84kB, file-rss:0kB, shmem-rss:0kB
  oom_reaper: unable to reap pid:7558 (a.out)
  a.out           D13272  7558   6931 0x00100084
  Call Trace:
   schedule+0x2d/0x80
   rwsem_down_write_failed+0x2bb/0x440
   call_rwsem_down_write_failed+0x13/0x20
   down_write+0x49/0x60
   unlink_file_vma+0x28/0x50
   free_pgtables+0x36/0x100
   exit_mmap+0xbb/0x180
   mmput+0x50/0x110
   copy_process.part.41+0xb61/0x1fe0
   _do_fork+0xe6/0x560
   do_syscall_64+0x74/0x230
   entry_SYSCALL_64_after_hwframe+0x42/0xb7

Link: http://lkml.kernel.org/r/201803221946.DHG65638.VFJHFtOSQLOMOF@I-love.SAKURA.ne.jp
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm/ksm: fix interaction with THP
Claudio Imbrenda [Thu, 5 Apr 2018 23:25:41 +0000 (16:25 -0700)]
mm/ksm: fix interaction with THP

This patch fixes a corner case for KSM.  When two pages belong or
belonged to the same transparent hugepage, and they should be merged,
KSM fails to split the page, and therefore no merging happens.

This bug can be reproduced by:
* making sure ksm is running (in case disabling ksmtuned)
* enabling transparent hugepages
* allocating a THP-aligned 1-THP-sized buffer
  e.g. on amd64: posix_memalign(&p, 1<<21, 1<<21)
* filling it with the same values
  e.g. memset(p, 42, 1<<21)
* performing madvise to make it mergeable
  e.g. madvise(p, 1<<21, MADV_MERGEABLE)
* waiting for KSM to perform a few scans

The expected outcome is that the all the pages get merged (1 shared and
the rest sharing); the actual outcome is that no pages get merged (1
unshared and the rest volatile)

The reason of this behaviour is that we increase the reference count
once for both pages we want to merge, but if they belong to the same
hugepage (or compound page), the reference counter used in both cases is
the one of the head of the compound page.  This means that
split_huge_page will find a value of the reference counter too high and
will fail.

This patch solves this problem by testing if the two pages to merge
belong to the same hugepage when attempting to merge them.  If so, the
hugepage is split safely.  This means that the hugepage is not split if
not necessary.

Link: http://lkml.kernel.org/r/1521548069-24758-1-git-send-email-imbrenda@linux.vnet.ibm.com
Signed-off-by: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com>
Co-authored-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm/memblock.c: cast constant ULLONG_MAX to phys_addr_t
Stefan Agner [Thu, 5 Apr 2018 23:25:38 +0000 (16:25 -0700)]
mm/memblock.c: cast constant ULLONG_MAX to phys_addr_t

This fixes a warning shown when phys_addr_t is 32-bit int when compiling
with clang:

  mm/memblock.c:927:15: warning: implicit conversion from 'unsigned long long'
        to 'phys_addr_t' (aka 'unsigned int') changes value from
        18446744073709551615 to 4294967295 [-Wconstant-conversion]
                                  r->base : ULLONG_MAX;
                                            ^~~~~~~~~~
  ./include/linux/kernel.h:30:21: note: expanded from macro 'ULLONG_MAX'
  #define ULLONG_MAX      (~0ULL)
                           ^~~~~

Link: http://lkml.kernel.org/r/20180319005645.29051-1-stefan@agner.ch
Signed-off-by: Stefan Agner <stefan@agner.ch>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoheaders: untangle kmemleak.h from mm.h
Randy Dunlap [Thu, 5 Apr 2018 23:25:34 +0000 (16:25 -0700)]
headers: untangle kmemleak.h from mm.h

Currently <linux/slab.h> #includes <linux/kmemleak.h> for no obvious
reason.  It looks like it's only a convenience, so remove kmemleak.h
from slab.h and add <linux/kmemleak.h> to any users of kmemleak_* that
don't already #include it.  Also remove <linux/kmemleak.h> from source
files that do not use it.

This is tested on i386 allmodconfig and x86_64 allmodconfig.  It would
be good to run it through the 0day bot for other $ARCHes.  I have
neither the horsepower nor the storage space for the other $ARCHes.

Update: This patch has been extensively build-tested by both the 0day
bot & kisskb/ozlabs build farms.  Both of them reported 2 build failures
for which patches are included here (in v2).

[ slab.h is the second most used header file after module.h; kernel.h is
  right there with slab.h. There could be some minor error in the
  counting due to some #includes having comments after them and I didn't
  combine all of those. ]

[akpm@linux-foundation.org: security/keys/big_key.c needs vmalloc.h, per sfr]
Link: http://lkml.kernel.org/r/e4309f98-3749-93e1-4bb7-d9501a39d015@infradead.org
Link: http://kisskb.ellerman.id.au/kisskb/head/13396/
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Reported-by: Michael Ellerman <mpe@ellerman.id.au> [2 build failures]
Reported-by: Fengguang Wu <fengguang.wu@intel.com> [2 build failures]
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Wei Yongjun <weiyongjun1@huawei.com>
Cc: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: John Johansen <john.johansen@canonical.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoinclude/linux/mmdebug.h: make VM_WARN* non-rvals
Michal Hocko [Thu, 5 Apr 2018 23:25:30 +0000 (16:25 -0700)]
include/linux/mmdebug.h: make VM_WARN* non-rvals

At present the construct

if (VM_WARN(...))

will compile OK with CONFIG_DEBUG_VM=y and will fail with
CONFIG_DEBUG_VM=n.  The reason is that VM_{WARN,BUG}* have always been
special wrt.  {WARN/BUG}* and never generate any code when DEBUG_VM is
disabled.  So we cannot really use it in conditionals.

We considered changing things so that this construct works in both cases
but that might cause unwanted code generation with CONFIG_DEBUG_VM=n.
It is safer and simpler to make the build fail in both cases.

[akpm@linux-foundation.org: changelog]
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm/page_isolation.c: make start_isolate_page_range() fail if already isolated
Mike Kravetz [Thu, 5 Apr 2018 23:25:26 +0000 (16:25 -0700)]
mm/page_isolation.c: make start_isolate_page_range() fail if already isolated

start_isolate_page_range() is used to set the migrate type of a set of
pageblocks to MIGRATE_ISOLATE while attempting to start a migration
operation.  It assumes that only one thread is calling it for the
specified range.  This routine is used by CMA, memory hotplug and
gigantic huge pages.  Each of these users synchronize access to the
range within their subsystem.  However, two subsystems (CMA and gigantic
huge pages for example) could attempt operations on the same range.  If
this happens, one thread may 'undo' the work another thread is doing.
This can result in pageblocks being incorrectly left marked as
MIGRATE_ISOLATE and therefore not available for page allocation.

What is ideally needed is a way to synchronize access to a set of
pageblocks that are undergoing isolation and migration.  The only thing
we know about these pageblocks is that they are all in the same zone.  A
per-node mutex is too coarse as we want to allow multiple operations on
different ranges within the same zone concurrently.  Instead, we will
use the migration type of the pageblocks themselves as a form of
synchronization.

start_isolate_page_range sets the migration type on a set of page-
blocks going in order from the one associated with the smallest pfn to
the largest pfn.  The zone lock is acquired to check and set the
migration type.  When going through the list of pageblocks check if
MIGRATE_ISOLATE is already set.  If so, this indicates another thread is
working on this pageblock.  We know exactly which pageblocks we set, so
clean up by undo those and return -EBUSY.

This allows start_isolate_page_range to serve as a synchronization
mechanism and will allow for more general use of callers making use of
these interfaces.  Update comments in alloc_contig_range to reflect this
new functionality.

Each CPU holds the associated zone lock to modify or examine the
migration type of a pageblock.  And, it will only examine/update a
single pageblock per lock acquire/release cycle.

Link: http://lkml.kernel.org/r/20180309224731.16978-1-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm: change return type to vm_fault_t
Souptick Joarder [Thu, 5 Apr 2018 23:25:23 +0000 (16:25 -0700)]
mm: change return type to vm_fault_t

The plan for these patches is to introduce the typedef, initially just
as documentation ("These functions should return a VM_FAULT_ status").
We'll trickle the patches to individual drivers/filesystems in through
the maintainers, as far as possible.  Then we'll change the typedef to
an unsigned int and break the compilation of any unconverted
drivers/filesystems.

vmf_insert_page(), vmf_insert_mixed() and vmf_insert_pfn() are three
newly added functions.  The various drivers/filesystems where return
value of fault(), huge_fault(), page_mkwrite() and pfn_mkwrite() get
converted, will need them.  These functions will return correct
VM_FAULT_ code based on err value.

We've had bugs before where drivers returned -EFOO.  And we have this
silly inefficiency where vm_insert_xxx() return an errno which (afaict)
every driver then converts into a VM_FAULT code.  In many cases drivers
failed to return correct VM_FAULT code value despite of vm_insert_xxx()
fails.  We have indentified and clean up all those existing bugs and
silly inefficiencies in driver/filesystems by adding these three new
inline wrappers.  As mentioned above, we will trickle those patches to
individual drivers/filesystems in through maintainers after these three
wrapper functions are merged.

Eventually we can convert vm_insert_xxx() into vmf_insert_xxx() and
remove these inline wrappers, but these are a good intermediate step.

Link: http://lkml.kernel.org/r/20180310162351.GA7422@jordon-HP-15-Notebook-PC
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm, oom: remove 3% bonus for CAP_SYS_ADMIN processes
David Rientjes [Thu, 5 Apr 2018 23:25:19 +0000 (16:25 -0700)]
mm, oom: remove 3% bonus for CAP_SYS_ADMIN processes

Since the 2.6 kernel, the oom killer has slightly biased away from
CAP_SYS_ADMIN processes by discounting some of its memory usage in
comparison to other processes.

This has always been implicit and nothing exactly relies on the
behavior.

Gaurav notices that __task_cred() can dereference a potentially freed
pointer if the task under consideration is exiting because a reference
to the task_struct is not held.

Remove the CAP_SYS_ADMIN bias so that all processes are treated equally.

If any CAP_SYS_ADMIN process would like to be biased against, it is
always allowed to adjust /proc/pid/oom_score_adj.

Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1803071548510.6996@chino.kir.corp.google.com
Signed-off-by: David Rientjes <rientjes@google.com>
Reported-by: Gaurav Kohli <gkohli@codeaurora.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm, page_alloc: wakeup kcompactd even if kswapd cannot free more memory
David Rientjes [Thu, 5 Apr 2018 23:25:16 +0000 (16:25 -0700)]
mm, page_alloc: wakeup kcompactd even if kswapd cannot free more memory

Kswapd will not wakeup if per-zone watermarks are not failing or if too
many previous attempts at background reclaim have failed.

This can be true if there is a lot of free memory available.  For high-
order allocations, kswapd is responsible for waking up kcompactd for
background compaction.  If the zone is not below its watermarks or
reclaim has recently failed (lots of free memory, nothing left to
reclaim), kcompactd does not get woken up.

When __GFP_DIRECT_RECLAIM is not allowed, allow kcompactd to still be
woken up even if kswapd will not reclaim.  This allows high-order
allocations, such as thp, to still trigger background compaction even
when the zone has an abundance of free memory.

Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1803111659420.209721@chino.kir.corp.google.com
Signed-off-by: David Rientjes <rientjes@google.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agokernel/fork.c: detect early free of a live mm
Mark Rutland [Thu, 5 Apr 2018 23:25:12 +0000 (16:25 -0700)]
kernel/fork.c: detect early free of a live mm

KASAN splats indicate that in some cases we free a live mm, then
continue to access it, with potentially disastrous results.  This is
likely due to a mismatched mmdrop() somewhere in the kernel, but so far
the culprit remains elusive.

Let's have __mmdrop() verify that the mm isn't live for the current
task, similar to the existing check for init_mm.  This way, we can catch
this class of issue earlier, and without requiring KASAN.

Currently, idle_task_exit() leaves active_mm stale after it switches to
init_mm.  This isn't harmful, but will trigger the new assertions, so we
must adjust idle_task_exit() to update active_mm.

Link: http://lkml.kernel.org/r/20180312140103.19235-1-mark.rutland@arm.com
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm: make counting of list_lru_one::nr_items lockless
Kirill Tkhai [Thu, 5 Apr 2018 23:25:08 +0000 (16:25 -0700)]
mm: make counting of list_lru_one::nr_items lockless

During the reclaiming slab of a memcg, shrink_slab iterates over all
registered shrinkers in the system, and tries to count and consume
objects related to the cgroup.  In case of memory pressure, this behaves
bad: I observe high system time and time spent in list_lru_count_one()
for many processes on RHEL7 kernel.

This patch makes list_lru_node::memcg_lrus rcu protected, that allows to
skip taking spinlock in list_lru_count_one().

Shakeel Butt with the patch observes significant perf graph change.  He
says:

========================================================================
Setup: running a fork-bomb in a memcg of 200MiB on a 8GiB and 4 vcpu
VM and recording the trace with 'perf record -g -a'.

The trace without the patch:

+  34.19%     fb.sh  [kernel.kallsyms]  [k] queued_spin_lock_slowpath
+  30.77%     fb.sh  [kernel.kallsyms]  [k] _raw_spin_lock
+   3.53%     fb.sh  [kernel.kallsyms]  [k] list_lru_count_one
+   2.26%     fb.sh  [kernel.kallsyms]  [k] super_cache_count
+   1.68%     fb.sh  [kernel.kallsyms]  [k] shrink_slab
+   0.59%     fb.sh  [kernel.kallsyms]  [k] down_read_trylock
+   0.48%     fb.sh  [kernel.kallsyms]  [k] _raw_spin_unlock_irqrestore
+   0.38%     fb.sh  [kernel.kallsyms]  [k] shrink_node_memcg
+   0.32%     fb.sh  [kernel.kallsyms]  [k] queue_work_on
+   0.26%     fb.sh  [kernel.kallsyms]  [k] count_shadow_nodes

With the patch:

+   0.16%     swapper  [kernel.kallsyms]    [k] default_idle
+   0.13%     oom_reaper  [kernel.kallsyms]    [k] mutex_spin_on_owner
+   0.05%     perf  [kernel.kallsyms]    [k] copy_user_generic_string
+   0.05%     init.real  [kernel.kallsyms]    [k] wait_consider_task
+   0.05%     kworker/0:0  [kernel.kallsyms]    [k] finish_task_switch
+   0.04%     kworker/2:1  [kernel.kallsyms]    [k] finish_task_switch
+   0.04%     kworker/3:1  [kernel.kallsyms]    [k] finish_task_switch
+   0.04%     kworker/1:0  [kernel.kallsyms]    [k] finish_task_switch
+   0.03%     binary  [kernel.kallsyms]    [k] copy_page
========================================================================

Thanks Shakeel for the testing.

[ktkhai@virtuozzo.com: v2]
Link: http://lkml.kernel.org/r/151203869520.3915.2587549826865799173.stgit@localhost.localdomain
Link: http://lkml.kernel.org/r/150583358557.26700.8490036563698102569.stgit@localhost.localdomain
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Tested-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm/swap_state.c: make bool enable_vma_readahead and swap_vma_readahead() static
Colin Ian King [Thu, 5 Apr 2018 23:25:05 +0000 (16:25 -0700)]
mm/swap_state.c: make bool enable_vma_readahead and swap_vma_readahead() static

The bool enable_vma_readahead and swap_vma_readahead() are local to the
source and do not need to be in global scope, so make them static.

Cleans up sparse warnings:

  mm/swap_state.c:41:6: warning: symbol 'enable_vma_readahead' was not declared. Should it be static?
  mm/swap_state.c:742:13: warning: symbol 'swap_vma_readahead' was not declared. Should it be static?

Link: http://lkml.kernel.org/r/20180223164852.5159-1-colin.king@canonical.com
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: "Huang, Ying" <ying.huang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoblock_invalidatepage(): only release page if the full page was invalidated
Jeff Moyer [Thu, 5 Apr 2018 23:25:01 +0000 (16:25 -0700)]
block_invalidatepage(): only release page if the full page was invalidated

Prior to commit d47992f86b30 ("mm: change invalidatepage prototype to
accept length"), an offset of 0 meant that the full page was being
invalidated.  After that commit, we need to instead check the length.

Jan said:
:
: The only possible issue is that try_to_release_page() was called more
: often than necessary.  Otherwise the issue is harmless but still it's good
: to have this fixed.

Link: http://lkml.kernel.org/r/x49fu5rtnzs.fsf@segfault.boston.devel.redhat.com
Fixes: d47992f86b307 ("mm: change invalidatepage prototype to accept length")
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Lukas Czerner <lczerner@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm: kernel-doc: add missing parameter descriptions
Mike Rapoport [Thu, 5 Apr 2018 23:24:57 +0000 (16:24 -0700)]
mm: kernel-doc: add missing parameter descriptions

Link: http://lkml.kernel.org/r/1519585191-10180-4-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm/swap.c: remove @cold parameter description for release_pages()
Mike Rapoport [Thu, 5 Apr 2018 23:24:53 +0000 (16:24 -0700)]
mm/swap.c: remove @cold parameter description for release_pages()

The 'cold' parameter was removed from release_pages function by commit
c6f92f9fbe7d ("mm: remove cold parameter for release_pages").

Update the description to match the code.

Link: http://lkml.kernel.org/r/1519585191-10180-3-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm/nommu: remove description of alloc_vm_area
Mike Rapoport [Thu, 5 Apr 2018 23:24:50 +0000 (16:24 -0700)]
mm/nommu: remove description of alloc_vm_area

The alloc_mm_area in nommu is a stub, but its description states it
allocates kernel address space.  Remove the description to make the code
and the documentation agree.

Link: http://lkml.kernel.org/r/1519585191-10180-2-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agozram: drop max_zpage_size and use zs_huge_class_size()
Sergey Senozhatsky [Thu, 5 Apr 2018 23:24:47 +0000 (16:24 -0700)]
zram: drop max_zpage_size and use zs_huge_class_size()

Remove ZRAM's enforced "huge object" value and use zsmalloc huge-class
watermark instead, which makes more sense.

TEST
- I used a 1G zram device, LZO compression back-end, original
  data set size was 444MB. Looking at zsmalloc classes stats the
  test ended up to be pretty fair.

BASE ZRAM/ZSMALLOC
=====================
zram mm_stat

498978816 191482495 199831552        0 199831552    15634        0

zsmalloc classes

 class  size almost_full almost_empty obj_allocated   obj_used pages_used pages_per_zspage freeable
...
   151  2448           0            0          1240       1240        744                3        0
   168  2720           0            0          4200       4200       2800                2        0
   190  3072           0            0         10100      10100       7575                3        0
   202  3264           0            0           380        380        304                4        0
   254  4096           0            0         10620      10620      10620                1        0

 Total                 7           46        106982     106187      48787                         0

PATCHED ZRAM/ZSMALLOC
=====================

zram mm_stat

498978816 182579184 194248704        0 194248704    15628        0

zsmalloc classes

 class  size almost_full almost_empty obj_allocated   obj_used pages_used pages_per_zspage freeable
...
   151  2448           0            0          1240       1240        744                3        0
   168  2720           0            0          4200       4200       2800                2        0
   190  3072           0            0         10100      10100       7575                3        0
   202  3264           0            0          7180       7180       5744                4        0
   254  4096           0            0          3820       3820       3820                1        0

 Total                 8           45        106959     106193      47424                         0

As we can see, we reduced the number of objects stored in class-4096,
because a huge number of objects which we previously forcibly stored in
class-4096 now stored in non-huge class-3264.  This results in lower
memory consumption:

- zsmalloc now uses 47424 physical pages, which is less than 48787 pages
  zsmalloc used before.

- objects that we store in class-3264 share zspages.  That's why overall
  the number of pages that both class-4096 and class-3264 consumed went
  down from 10924 to 9564.

[sergey.senozhatsky.work@gmail.com: add pool param to zs_huge_class_size()]
Link: http://lkml.kernel.org/r/20180314081833.1096-3-sergey.senozhatsky@gmail.com
Link: http://lkml.kernel.org/r/20180306070639.7389-3-sergey.senozhatsky@gmail.com
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agozsmalloc: introduce zs_huge_class_size()
Sergey Senozhatsky [Thu, 5 Apr 2018 23:24:43 +0000 (16:24 -0700)]
zsmalloc: introduce zs_huge_class_size()

Patch series "zsmalloc/zram: drop zram's max_zpage_size", v3.

ZRAM's max_zpage_size is a bad thing.  It forces zsmalloc to store
normal objects as huge ones, which results in bigger zsmalloc memory
usage.  Drop it and use actual zsmalloc huge-class value when decide if
the object is huge or not.

This patch (of 2):

Not every object can be share its zspage with other objects, e.g.  when
the object is as big as zspage or nearly as big a zspage.  For such
objects zsmalloc has a so called huge class - every object which belongs
to huge class consumes the entire zspage (which consists of a physical
page).  On x86_64, PAGE_SHIFT 12 box, the first non-huge class size is
3264, so starting down from size 3264, objects can share page(-s) and
thus minimize memory wastage.

ZRAM, however, has its own statically defined watermark for huge
objects, namely "3 * PAGE_SIZE / 4 = 3072", and forcibly stores every
object larger than this watermark (3072) as a PAGE_SIZE object, in other
words, to a huge class, while zsmalloc can keep some of those objects in
non-huge classes.  This results in increased memory consumption.

zsmalloc knows better if the object is huge or not.  Introduce
zs_huge_class_size() function which tells if the given object can be
stored in one of non-huge classes or not.  This will let us to drop
ZRAM's huge object watermark and fully rely on zsmalloc when we decide
if the object is huge.

[sergey.senozhatsky.work@gmail.com: add pool param to zs_huge_class_size()]
Link: http://lkml.kernel.org/r/20180314081833.1096-2-sergey.senozhatsky@gmail.com
Link: http://lkml.kernel.org/r/20180306070639.7389-2-sergey.senozhatsky@gmail.com
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm: fix races between swapoff and flush dcache
Huang Ying [Thu, 5 Apr 2018 23:24:39 +0000 (16:24 -0700)]
mm: fix races between swapoff and flush dcache

Thanks to commit 4b3ef9daa4fc ("mm/swap: split swap cache into 64MB
trunks"), after swapoff the address_space associated with the swap
device will be freed.  So page_mapping() users which may touch the
address_space need some kind of mechanism to prevent the address_space
from being freed during accessing.

The dcache flushing functions (flush_dcache_page(), etc) in architecture
specific code may access the address_space of swap device for anonymous
pages in swap cache via page_mapping() function.  But in some cases
there are no mechanisms to prevent the swap device from being swapoff,
for example,

  CPU1 CPU2
  __get_user_pages() swapoff()
    flush_dcache_page()
      mapping = page_mapping()
        ...   exit_swap_address_space()
        ...     kvfree(spaces)
        mapping_mapped(mapping)

The address space may be accessed after being freed.

But from cachetlb.txt and Russell King, flush_dcache_page() only care
about file cache pages, for anonymous pages, flush_anon_page() should be
used.  The implementation of flush_dcache_page() in all architectures
follows this too.  They will check whether page_mapping() is NULL and
whether mapping_mapped() is true to determine whether to flush the
dcache immediately.  And they will use interval tree (mapping->i_mmap)
to find all user space mappings.  While mapping_mapped() and
mapping->i_mmap isn't used by anonymous pages in swap cache at all.

So, to fix the race between swapoff and flush dcache, __page_mapping()
is add to return the address_space for file cache pages and NULL
otherwise.  All page_mapping() invoking in flush dcache functions are
replaced with page_mapping_file().

[akpm@linux-foundation.org: simplify page_mapping_file(), per Mike]
Link: http://lkml.kernel.org/r/20180305083634.15174-1-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Chen Liqin <liqin.linux@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Zankel <chris@zankel.net>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agofs/direct-io.c: minor cleanups in do_blockdev_direct_IO
Nikolay Borisov [Thu, 5 Apr 2018 23:24:36 +0000 (16:24 -0700)]
fs/direct-io.c: minor cleanups in do_blockdev_direct_IO

We already get the block counts and calculate the end block at the
beginning of the function.  Let's use the local variables for
consistency and readability.  No functional changes

[akpm@linux-foundation.org: constify the locals to prevent future slipups]
Link: http://lkml.kernel.org/r/1519638870-17756-1-git-send-email-nborisov@suse.com
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoinclude/linux/mm.h: provide consistent declaration for num_poisoned_pages
Guenter Roeck [Thu, 5 Apr 2018 23:24:32 +0000 (16:24 -0700)]
include/linux/mm.h: provide consistent declaration for num_poisoned_pages

clang reports the following compile warning.

  In file included from mm/vmscan.c:56:
  ./include/linux/swapops.h:327:22: warning:
section attribute is specified on redeclared variable [-Wsection]
  extern atomic_long_t num_poisoned_pages __read_mostly;
                       ^
  ./include/linux/mm.h:2585:22: note: previous declaration is here
  extern atomic_long_t num_poisoned_pages;
                     ^

Let's use __read_mostly everywhere.

Link: http://lkml.kernel.org/r/1519686565-8224-1-git-send-email-linux@roeck-us.net
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthias Kaehlcke <mka@chromium.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agodevice-dax: implement ->pagesize() for smaps to report MMUPageSize
Dan Williams [Thu, 5 Apr 2018 23:24:28 +0000 (16:24 -0700)]
device-dax: implement ->pagesize() for smaps to report MMUPageSize

Given that device-dax is making similar page mapping size guarantees as
hugetlbfs, emit the size in smaps and any other kernel path that
requests the mapping size of a vma.

Link: http://lkml.kernel.org/r/151996255287.27922.18397777516059080245.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reported-by: Jane Chu <jane.chu@oracle.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm, hugetlbfs: introduce ->pagesize() to vm_operations_struct
Dan Williams [Thu, 5 Apr 2018 23:24:25 +0000 (16:24 -0700)]
mm, hugetlbfs: introduce ->pagesize() to vm_operations_struct

When device-dax is operating in huge-page mode we want it to behave like
hugetlbfs and report the MMU page mapping size that is being enforced by
the vma.

Similar to commit 31383c6865a5 "mm, hugetlbfs: introduce ->split() to
vm_operations_struct" it would be messy to teach vma_mmu_pagesize()
about device-dax page mapping sizes in the same (hstate) way that
hugetlbfs communicates this attribute.  Instead, these patches introduce
a new ->pagesize() vm operation.

Link: http://lkml.kernel.org/r/151996254734.27922.15813097401404359642.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reported-by: Jane Chu <jane.chu@oracle.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm, powerpc: use vma_kernel_pagesize() in vma_mmu_pagesize()
Dan Williams [Thu, 5 Apr 2018 23:24:21 +0000 (16:24 -0700)]
mm, powerpc: use vma_kernel_pagesize() in vma_mmu_pagesize()

Patch series "mm, smaps: MMUPageSize for device-dax", v3.

Similar to commit 31383c6865a5 ("mm, hugetlbfs: introduce ->split() to
vm_operations_struct") here is another occasion where we want
special-case hugetlbfs/hstate enabling to also apply to device-dax.

This prompts the question what other hstate conversions we might do
beyond ->split() and ->pagesize(), but this appears to be the last of
the usages of hstate_vma() in generic/non-hugetlbfs specific code paths.

This patch (of 3):

The current powerpc definition of vma_mmu_pagesize() open codes looking
up the page size via hstate.  It is identical to the generic
vma_kernel_pagesize() implementation.

Now, vma_kernel_pagesize() is growing support for determining the page
size of Device-DAX vmas in addition to the existing Hugetlbfs page size
determination.

Ideally, if the powerpc vma_mmu_pagesize() used vma_kernel_pagesize() it
would automatically benefit from any new vma-type support that is added
to vma_kernel_pagesize().  However, the powerpc vma_mmu_pagesize() is
prevented from calling vma_kernel_pagesize() due to a circular header
dependency that requires vma_mmu_pagesize() to be defined before
including <linux/hugetlb.h>.

Break this circular dependency by defining the default vma_mmu_pagesize()
as a __weak symbol to be overridden by the powerpc version.

Link: http://lkml.kernel.org/r/151996254179.27922.2213728278535578744.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Jane Chu <jane.chu@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm/gup.c: fix coding style issues.
Mario Leinweber [Thu, 5 Apr 2018 23:24:18 +0000 (16:24 -0700)]
mm/gup.c: fix coding style issues.

- Fixed style error: 8 spaces -> 1 tab.
- Fixed style warning: Corrected misleading indentation.

Link: http://lkml.kernel.org/r/20180302210254.31888-1-marioleinweber@web.de
Signed-off-by: Mario Leinweber <marioleinweber@web.de>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm/free_pcppages_bulk: prefetch buddy while not holding lock
Aaron Lu [Thu, 5 Apr 2018 23:24:14 +0000 (16:24 -0700)]
mm/free_pcppages_bulk: prefetch buddy while not holding lock

When a page is freed back to the global pool, its buddy will be checked
to see if it's possible to do a merge.  This requires accessing buddy's
page structure and that access could take a long time if it's cache
cold.

This patch adds a prefetch to the to-be-freed page's buddy outside of
zone->lock in hope of accessing buddy's page structure later under
zone->lock will be faster.  Since we *always* do buddy merging and check
an order-0 page's buddy to try to merge it when it goes into the main
allocator, the cacheline will always come in, i.e.  the prefetched data
will never be unused.

Normally, the number of prefetch will be pcp->batch(default=31 and has
an upper limit of (PAGE_SHIFT * 8)=96 on x86_64) but in the case of
pcp's pages get all drained, it will be pcp->count which has an upper
limit of pcp->high.  pcp->high, although has a default value of 186
(pcp->batch=31 * 6), can be changed by user through
/proc/sys/vm/percpu_pagelist_fraction and there is no software upper
limit so could be large, like several thousand.  For this reason, only
the first pcp->batch number of page's buddy structure is prefetched to
avoid excessive prefetching.

In the meantime, there are two concerns:

 1. the prefetch could potentially evict existing cachelines, especially
    for L1D cache since it is not huge

 2. there is some additional instruction overhead, namely calculating
    buddy pfn twice

For 1, it's hard to say, this microbenchmark though shows good result
but the actual benefit of this patch will be workload/CPU dependant;

For 2, since the calculation is a XOR on two local variables, it's
expected in many cases that cycles spent will be offset by reduced
memory latency later.  This is especially true for NUMA machines where
multiple CPUs are contending on zone->lock and the most time consuming
part under zone->lock is the wait of 'struct page' cacheline of the
to-be-freed pages and their buddies.

Test with will-it-scale/page_fault1 full load:

  kernel      Broadwell(2S)  Skylake(2S)   Broadwell(4S)  Skylake(4S)
  v4.16-rc2+  9034215        7971818       13667135       15677465
  patch2/3    9536374 +5.6%  8314710 +4.3% 14070408 +3.0% 16675866 +6.4%
  this patch 10180856 +6.8%  8506369 +2.3% 14756865 +4.9% 17325324 +3.9%

Note: this patch's performance improvement percent is against patch2/3.

(Changelog stolen from Dave Hansen and Mel Gorman's comments at
http://lkml.kernel.org/r/148a42d8-8306-2f2f-7f7c-86bc118f8ccd@intel.com)

[aaron.lu@intel.com: use helper function, avoid disordering pages]
Link: http://lkml.kernel.org/r/20180301062845.26038-4-aaron.lu@intel.com
Link: http://lkml.kernel.org/r/20180320113146.GB24737@intel.com
[aaron.lu@intel.com: v4]
Link: http://lkml.kernel.org/r/20180301062845.26038-4-aaron.lu@intel.com
Link: http://lkml.kernel.org/r/20180309082431.GB30868@intel.com
Link: http://lkml.kernel.org/r/20180301062845.26038-4-aaron.lu@intel.com
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Suggested-by: Ying Huang <ying.huang@intel.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Kemi Wang <kemi.wang@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm/free_pcppages_bulk: do not hold lock when picking pages to free
Aaron Lu [Thu, 5 Apr 2018 23:24:10 +0000 (16:24 -0700)]
mm/free_pcppages_bulk: do not hold lock when picking pages to free

When freeing a batch of pages from Per-CPU-Pages(PCP) back to buddy, the
zone->lock is held and then pages are chosen from PCP's migratetype
list.  While there is actually no need to do this 'choose part' under
lock since it's PCP pages, the only CPU that can touch them is us and
irq is also disabled.

Moving this part outside could reduce lock held time and improve
performance.  Test with will-it-scale/page_fault1 full load:

  kernel      Broadwell(2S)  Skylake(2S)   Broadwell(4S)  Skylake(4S)
  v4.16-rc2+  9034215        7971818       13667135       15677465
  this patch  9536374 +5.6%  8314710 +4.3% 14070408 +3.0% 16675866 +6.4%

What the test does is: starts $nr_cpu processes and each will repeatedly
do the following for 5 minutes:

 - mmap 128M anonymouse space

 - write access to that space

 - munmap.

The score is the aggregated iteration.

https://github.com/antonblanchard/will-it-scale/blob/master/tests/page_fault1.c

Link: http://lkml.kernel.org/r/20180301062845.26038-3-aaron.lu@intel.com
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Kemi Wang <kemi.wang@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm/free_pcppages_bulk: update pcp->count inside
Aaron Lu [Thu, 5 Apr 2018 23:24:06 +0000 (16:24 -0700)]
mm/free_pcppages_bulk: update pcp->count inside

Matthew Wilcox found that all callers of free_pcppages_bulk() currently
update pcp->count immediately after so it's natural to do it inside
free_pcppages_bulk().

No functionality or performance change is expected from this patch.

Link: http://lkml.kernel.org/r/20180301062845.26038-2-aaron.lu@intel.com
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Suggested-by: Matthew Wilcox <willy@infradead.org>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kemi Wang <kemi.wang@intel.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm, compaction: drain pcps for zone when kcompactd fails
David Rientjes [Thu, 5 Apr 2018 23:24:02 +0000 (16:24 -0700)]
mm, compaction: drain pcps for zone when kcompactd fails

It's possible for free pages to become stranded on per-cpu pagesets
(pcps) that, if drained, could be merged with buddy pages on the zone's
free area to form large order pages, including up to MAX_ORDER.

Consider a verbose example using the tools/vm/page-types tool at the
beginning of a ZONE_NORMAL ('B' indicates a buddy page and 'S' indicates
a slab page).  Pages on pcps do not have any page flags set.

  109954  1       _______S________________________________________________________
  109955  2       __________B_____________________________________________________
  109957  1       ________________________________________________________________
  109958  1       __________B_____________________________________________________
  109959  7       ________________________________________________________________
  109960  1       __________B_____________________________________________________
  109961  9       ________________________________________________________________
  10996a  1       __________B_____________________________________________________
  10996b  3       ________________________________________________________________
  10996e  1       __________B_____________________________________________________
  10996f  1       ________________________________________________________________
  ...
  109f8c  1       __________B_____________________________________________________
  109f8d  2       ________________________________________________________________
  109f8f  2       __________B_____________________________________________________
  109f91  f       ________________________________________________________________
  109fa0  1       __________B_____________________________________________________
  109fa1  7       ________________________________________________________________
  109fa8  1       __________B_____________________________________________________
  109fa9  1       ________________________________________________________________
  109faa  1       __________B_____________________________________________________
  109fab  1       _______S________________________________________________________

The compaction migration scanner is attempting to defragment this memory
since it is at the beginning of the zone.  It has done so quite well,
all movable pages have been migrated.  From pfn [0x109955, 0x109fab),
there are only buddy pages and pages without flags set.

These pages may be stranded on pcps that could otherwise allow this
memory to be coalesced if freed back to the zone free area.  It is
possible that some of these pages may not be on pcps and that something
has called alloc_pages() and used the memory directly, but we rely on
the absence of __GFP_MOVABLE in these cases to allocate from
MIGATE_UNMOVABLE pageblocks to try to keep these MIGRATE_MOVABLE
pageblocks as free as possible.

These buddy and pcp pages, spanning 1,621 pages, could be coalesced and
allow for three transparent hugepages to be dynamically allocated.
Running the numbers for all such spans on the system, it was found that
there were over 400 such spans of only buddy pages and pages without
flags set at the time this /proc/kpageflags sample was collected.
Without this support, there were _no_ order-9 or order-10 pages free.

When kcompactd fails to defragment memory such that a cc.order page can
be allocated, drain all pcps for the zone back to the buddy allocator so
this stranding cannot occur.  Compaction for that order will
subsequently be deferred, which acts as a ratelimit on this drain.

Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1803010340100.88270@chino.kir.corp.google.com
Signed-off-by: David Rientjes <rientjes@google.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm: make should_failslab always available for fault injection
Howard McLauchlan [Thu, 5 Apr 2018 23:23:57 +0000 (16:23 -0700)]
mm: make should_failslab always available for fault injection

should_failslab() is a convenient function to hook into for directed
error injection into kmalloc().  However, it is only available if a
config flag is set.

The following BCC script, for example, fails kmalloc() calls after a
btrfs umount:

    from bcc import BPF

    prog = r"""
    BPF_HASH(flag);

    #include <linux/mm.h>

    int kprobe__btrfs_close_devices(void *ctx) {
            u64 key = 1;
            flag.update(&key, &key);
            return 0;
    }

    int kprobe__should_failslab(struct pt_regs *ctx) {
            u64 key = 1;
            u64 *res;
            res = flag.lookup(&key);
            if (res != 0) {
                bpf_override_return(ctx, -ENOMEM);
            }
            return 0;
    }
    """
    b = BPF(text=prog)

    while 1:
        b.kprobe_poll()

This patch refactors the should_failslab implementation so that the
function is always available for error injection, independent of flags.

This change would be similar in nature to commit f5490d3ec921 ("block:
Add should_fail_bio() for bpf error injection").

Link: http://lkml.kernel.org/r/20180222020320.6944-1-hmclauchlan@fb.com
Signed-off-by: Howard McLauchlan <hmclauchlan@fb.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: Johannes Weiner <jweiner@fb.com>
Cc: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm/page_poison.c: make early_page_poison_param() __init
Dou Liyang [Thu, 5 Apr 2018 23:23:53 +0000 (16:23 -0700)]
mm/page_poison.c: make early_page_poison_param() __init

The early_param() is only called during kernel initialization, So Linux
marks the function of it with __init macro to save memory.

But it forgot to mark the early_page_poison_param().  So, Make it __init
as well.

Link: http://lkml.kernel.org/r/20180117034757.27024-1-douly.fnst@cn.fujitsu.com
Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm/page_owner.c: make early_page_owner_param() __init
Dou Liyang [Thu, 5 Apr 2018 23:23:49 +0000 (16:23 -0700)]
mm/page_owner.c: make early_page_owner_param() __init

The early_param() is only called during kernel initialization, So Linux
marks the functions of it with __init macro to save memory.

But it forgot to mark the early_page_owner_param().  So, Make it __init
as well.

Link: http://lkml.kernel.org/r/20180117034736.26963-1-douly.fnst@cn.fujitsu.com
Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm/kmemleak.c: make kmemleak_boot_config() __init
Dou Liyang [Thu, 5 Apr 2018 23:23:46 +0000 (16:23 -0700)]
mm/kmemleak.c: make kmemleak_boot_config() __init

The early_param() is only called during kernel initialization, So Linux
marks the functions of it with __init macro to save memory.

But it forgot to mark the kmemleak_boot_config().  So, Make it __init as
well.

Link: http://lkml.kernel.org/r/20180117034720.26897-1-douly.fnst@cn.fujitsu.com
Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm: swap: unify cluster-based and vma-based swap readahead
Minchan Kim [Thu, 5 Apr 2018 23:23:42 +0000 (16:23 -0700)]
mm: swap: unify cluster-based and vma-based swap readahead

This patch makes do_swap_page() not need to be aware of two different
swap readahead algorithms.  Just unify cluster-based and vma-based
readahead function call.

Link: http://lkml.kernel.org/r/1509520520-32367-3-git-send-email-minchan@kernel.org
Link: http://lkml.kernel.org/r/20180220085249.151400-3-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm: swap: clean up swap readahead
Minchan Kim [Thu, 5 Apr 2018 23:23:39 +0000 (16:23 -0700)]
mm: swap: clean up swap readahead

When I see recent change of swap readahead, I am very unhappy about
current code structure which diverges two swap readahead algorithm in
do_swap_page.  This patch is to clean it up.

Main motivation is that fault handler doesn't need to be aware of
readahead algorithms but just should call swapin_readahead.

As first step, this patch cleans up a little bit but not perfect (I just
separate for review easier) so next patch will make the goal complete.

[minchan@kernel.org: do not check readahead flag with THP anon]
Link: http://lkml.kernel.org/r/874lm83zho.fsf@yhuang-dev.intel.com
Link: http://lkml.kernel.org/r/20180227232611.169883-1-minchan@kernel.org
Link: http://lkml.kernel.org/r/1509520520-32367-2-git-send-email-minchan@kernel.org
Link: http://lkml.kernel.org/r/20180220085249.151400-2-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm,vmscan: don't pretend forward progress upon shrinker_rwsem contention
Tetsuo Handa [Thu, 5 Apr 2018 23:23:35 +0000 (16:23 -0700)]
mm,vmscan: don't pretend forward progress upon shrinker_rwsem contention

Since we no longer use return value of shrink_slab() for normal reclaim,
the comment is no longer true.  If some do_shrink_slab() call takes
unexpectedly long (root cause of stall is currently unknown) when
register_shrinker()/unregister_shrinker() is pending, trying to drop
caches via /proc/sys/vm/drop_caches could become infinite cond_resched()
loop if many mem_cgroup are defined.  For safety, let's not pretend
forward progress.

Link: http://lkml.kernel.org/r/201802202229.GGF26507.LVFtMSOOHFJOQF@I-love.SAKURA.ne.jp
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Glauber Costa <glommer@gmail.com>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoz3fold: limit use of stale list for allocation
Vitaly Wool [Thu, 5 Apr 2018 23:23:32 +0000 (16:23 -0700)]
z3fold: limit use of stale list for allocation

Currently if z3fold couldn't find an unbuddied page it would first try
to pull a page off the stale list.  The problem with this approach is
that we can't 100% guarantee that the page is not processed by the
workqueue thread at the same time unless we run cancel_work_sync() on
it, which we can't do if we're in an atomic context.  So let's just
limit stale list usage to non-atomic contexts only.

Link: http://lkml.kernel.org/r/47ab51e7-e9c1-d30e-ab17-f734dbc3abce@gmail.com
Signed-off-by: Vitaly Vul <vitaly.vul@sony.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: <Oleksiy.Avramchenko@sony.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm/huge_memory.c: reorder operations in __split_huge_page_tail()
Konstantin Khlebnikov [Thu, 5 Apr 2018 23:23:28 +0000 (16:23 -0700)]
mm/huge_memory.c: reorder operations in __split_huge_page_tail()

THP split makes non-atomic change of tail page flags.  This is almost ok
because tail pages are locked and isolated but this breaks recent
changes in page locking: non-atomic operation could clear bit
PG_waiters.

As a result concurrent sequence get_page_unless_zero() -> lock_page()
might block forever.  Especially if this page was truncated later.

Fix is trivial: clone flags before unfreezing page reference counter.

This race exists since commit 62906027091f ("mm: add PageWaiters
indicating tasks are waiting for a page bit") while unsave unfreeze
itself was added in commit 8df651c7059e ("thp: cleanup
split_huge_page()").

clear_compound_head() also must be called before unfreezing page
reference because after successful get_page_unless_zero() might follow
put_page() which needs correct compound_head().

And replace page_ref_inc()/page_ref_add() with page_ref_unfreeze() which
is made especially for that and has semantic of smp_store_release().

Link: http://lkml.kernel.org/r/151844393341.210639.13162088407980624477.stgit@buzz
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm/page_ref: use atomic_set_release in page_ref_unfreeze
Konstantin Khlebnikov [Thu, 5 Apr 2018 23:23:24 +0000 (16:23 -0700)]
mm/page_ref: use atomic_set_release in page_ref_unfreeze

page_ref_unfreeze() has exactly that semantic.  No functional changes:
just minus one barrier and proper handling of PPro errata.

Link: http://lkml.kernel.org/r/151844393004.210639.4672319312617954272.stgit@buzz
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm: fix races between address_space dereference and free in page_evicatable
Huang Ying [Thu, 5 Apr 2018 23:23:20 +0000 (16:23 -0700)]
mm: fix races between address_space dereference and free in page_evicatable

When page_mapping() is called and the mapping is dereferenced in
page_evicatable() through shrink_active_list(), it is possible for the
inode to be truncated and the embedded address space to be freed at the
same time.  This may lead to the following race.

CPU1                                                CPU2

truncate(inode)                                     shrink_active_list()
  ...                                                 page_evictable(page)
  truncate_inode_page(mapping, page);
    delete_from_page_cache(page)
      spin_lock_irqsave(&mapping->tree_lock, flags);
        __delete_from_page_cache(page, NULL)
          page_cache_tree_delete(..)
            ...                                         mapping = page_mapping(page);
            page->mapping = NULL;
            ...
      spin_unlock_irqrestore(&mapping->tree_lock, flags);
      page_cache_free_page(mapping, page)
        put_page(page)
          if (put_page_testzero(page)) -> false
- inode now has no pages and can be freed including embedded address_space

                                                        mapping_unevictable(mapping)
  test_bit(AS_UNEVICTABLE, &mapping->flags);
- we've dereferenced mapping which is potentially already free.

Similar race exists between swap cache freeing and page_evicatable()
too.

The address_space in inode and swap cache will be freed after a RCU
grace period.  So the races are fixed via enclosing the page_mapping()
and address_space usage in rcu_read_lock/unlock().  Some comments are
added in code to make it clear what is protected by the RCU read lock.

Link: http://lkml.kernel.org/r/20180212081227.1940-1-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Minchan Kim <minchan@kernel.org>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm: reuse DEFINE_SHOW_ATTRIBUTE() macro
Andy Shevchenko [Thu, 5 Apr 2018 23:23:16 +0000 (16:23 -0700)]
mm: reuse DEFINE_SHOW_ATTRIBUTE() macro

...instead of open coding file operations followed by custom ->open()
callbacks per each attribute.

[andriy.shevchenko@linux.intel.com: add tags, fix compilation issue]
Link: http://lkml.kernel.org/r/20180217144253.58604-1-andriy.shevchenko@linux.intel.com
Link: http://lkml.kernel.org/r/20180214154644.54505-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Dennis Zhou <dennisszhou@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm, page_alloc: move mirrored_kernelcore to __meminitdata
David Rientjes [Thu, 5 Apr 2018 23:23:12 +0000 (16:23 -0700)]
mm, page_alloc: move mirrored_kernelcore to __meminitdata

mirrored_kernelcore can be in __meminitdata, so move it there.

At the same time, fixup section specifiers to be after the name of the
variable per checkpatch.

Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1802121623280.179479@chino.kir.corp.google.com
Signed-off-by: David Rientjes <rientjes@google.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm, page_alloc: extend kernelcore and movablecore for percent
David Rientjes [Thu, 5 Apr 2018 23:23:09 +0000 (16:23 -0700)]
mm, page_alloc: extend kernelcore and movablecore for percent

Both kernelcore= and movablecore= can be used to define the amount of
ZONE_NORMAL and ZONE_MOVABLE on a system, respectively.  This requires
the system memory capacity to be known when specifying the command line,
however.

This introduces the ability to define both kernelcore= and movablecore=
as a percentage of total system memory.  This is convenient for systems
software that wants to define the amount of ZONE_MOVABLE, for example,
as a proportion of a system's memory rather than a hardcoded byte value.

To define the percentage, the final character of the parameter should be
a '%'.

mhocko: "why is anyone using these options nowadays?"

rientjes:
:
: Fragmentation of non-__GFP_MOVABLE pages due to low on memory
: situations can pollute most pageblocks on the system, as much as 1GB of
: slab being fragmented over 128GB of memory, for example.  When the
: amount of kernel memory is well bounded for certain systems, it is
: better to aggressively reclaim from existing MIGRATE_UNMOVABLE
: pageblocks rather than eagerly fallback to others.
:
: We have additional patches that help with this fragmentation if you're
: interested, specifically kcompactd compaction of MIGRATE_UNMOVABLE
: pageblocks triggered by fallback of non-__GFP_MOVABLE allocations and
: draining of pcp lists back to the zone free area to prevent stranding.

[rientjes@google.com: updates]
Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1802131700160.71590@chino.kir.corp.google.com
Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1802121622470.179479@chino.kir.corp.google.com
Signed-off-by: David Rientjes <rientjes@google.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm: hwpoison: disable memory error handling on 1GB hugepage
Naoya Horiguchi [Thu, 5 Apr 2018 23:23:05 +0000 (16:23 -0700)]
mm: hwpoison: disable memory error handling on 1GB hugepage

Recently the following BUG was reported:

    Injecting memory failure for pfn 0x3c0000 at process virtual address 0x7fe300000000
    Memory failure: 0x3c0000: recovery action for huge page: Recovered
    BUG: unable to handle kernel paging request at ffff8dfcc0003000
    IP: gup_pgd_range+0x1f0/0xc20
    PGD 17ae72067 P4D 17ae72067 PUD 0
    Oops: 0000 [#1] SMP PTI
    ...
    CPU: 3 PID: 5467 Comm: hugetlb_1gb Not tainted 4.15.0-rc8-mm1-abc+ #3
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.3-1.fc25 04/01/2014

You can easily reproduce this by calling madvise(MADV_HWPOISON) twice on
a 1GB hugepage.  This happens because get_user_pages_fast() is not aware
of a migration entry on pud that was created in the 1st madvise() event.

I think that conversion to pud-aligned migration entry is working, but
other MM code walking over page table isn't prepared for it.  We need
some time and effort to make all this work properly, so this patch
avoids the reported bug by just disabling error handling for 1GB
hugepage.

[n-horiguchi@ah.jp.nec.com: v2]
Link: http://lkml.kernel.org/r/1517284444-18149-1-git-send-email-n-horiguchi@ah.jp.nec.com
Link: http://lkml.kernel.org/r/1517207283-15769-1-git-send-email-n-horiguchi@ah.jp.nec.com
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Punit Agrawal <punit.agrawal@arm.com>
Tested-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm/memory_hotplug: optimize memory hotplug
Pavel Tatashin [Thu, 5 Apr 2018 23:23:00 +0000 (16:23 -0700)]
mm/memory_hotplug: optimize memory hotplug

During memory hotplugging we traverse struct pages three times:

1. memset(0) in sparse_add_one_section()
2. loop in __add_section() to set do: set_page_node(page, nid); and
   SetPageReserved(page);
3. loop in memmap_init_zone() to call __init_single_pfn()

This patch removes the first two loops, and leaves only loop 3.  All
struct pages are initialized in one place, the same as it is done during
boot.

The benefits:

 - We improve memory hotplug performance because we are not evicting the
   cache several times and also reduce loop branching overhead.

 - Remove condition from hotpath in __init_single_pfn(), that was added
   in order to fix the problem that was reported by Bharata in the above
   email thread, thus also improve performance during normal boot.

 - Make memory hotplug more similar to the boot memory initialization
   path because we zero and initialize struct pages only in one
   function.

 - Simplifies memory hotplug struct page initialization code, and thus
   enables future improvements, such as multi-threading the
   initialization of struct pages in order to improve hotplug
   performance even further on larger machines.

[pasha.tatashin@oracle.com: v5]
Link: http://lkml.kernel.org/r/20180228030308.1116-7-pasha.tatashin@oracle.com
Link: http://lkml.kernel.org/r/20180215165920.8570-7-pasha.tatashin@oracle.com
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Bharata B Rao <bharata@linux.vnet.ibm.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm/memory_hotplug: don't read nid from struct page during hotplug
Pavel Tatashin [Thu, 5 Apr 2018 23:22:56 +0000 (16:22 -0700)]
mm/memory_hotplug: don't read nid from struct page during hotplug

During memory hotplugging the probe routine will leave struct pages
uninitialized, the same as it is currently done during boot.  Therefore,
we do not want to access the inside of struct pages before
__init_single_page() is called during onlining.

Because during hotplug we know that pages in one memory block belong to
the same numa node, we can skip the checking.  We should keep checking
for the boot case.

[pasha.tatashin@oracle.com: s/register_new_memory()/hotplug_memory_register()]
Link: http://lkml.kernel.org/r/20180228030308.1116-6-pasha.tatashin@oracle.com
Link: http://lkml.kernel.org/r/20180215165920.8570-6-pasha.tatashin@oracle.com
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Bharata B Rao <bharata@linux.vnet.ibm.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm/memory_hotplug: optimize probe routine
Pavel Tatashin [Thu, 5 Apr 2018 23:22:52 +0000 (16:22 -0700)]
mm/memory_hotplug: optimize probe routine

When memory is hotplugged pages_correctly_reserved() is called to verify
that the added memory is present, this routine traverses through every
struct page and verifies that PageReserved() is set.  This is a slow
operation especially if a large amount of memory is added.

Instead of checking every page, it is enough to simply check that the
section is present, has mapping (struct page array is allocated), and
the mapping is online.

In addition, we should not excpect that probe routine sets flags in
struct page, as the struct pages have not yet been initialized.  The
initialization should be done in __init_single_page(), the same as
during boot.

Link: http://lkml.kernel.org/r/20180215165920.8570-5-pasha.tatashin@oracle.com
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Bharata B Rao <bharata@linux.vnet.ibm.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm: uninitialized struct page poisoning sanity checking
Pavel Tatashin [Thu, 5 Apr 2018 23:22:47 +0000 (16:22 -0700)]
mm: uninitialized struct page poisoning sanity checking

During boot we poison struct page memory in order to ensure that no one
is accessing this memory until the struct pages are initialized in
__init_single_page().

This patch adds more scrutiny to this checking by making sure that flags
do not equal the poison pattern when they are accessed.  The pattern is
all ones.

Since node id is also stored in struct page, and may be accessed quite
early, we add this enforcement into page_to_nid() function as well.
Note, this is applicable only when NODE_NOT_IN_PAGE_FLAGS=n

[pasha.tatashin@oracle.com: v4]
Link: http://lkml.kernel.org/r/20180215165920.8570-4-pasha.tatashin@oracle.com
Link: http://lkml.kernel.org/r/20180213193159.14606-4-pasha.tatashin@oracle.com
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Bharata B Rao <bharata@linux.vnet.ibm.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agox86/mm/memory_hotplug: determine block size based on the end of boot memory
Pavel Tatashin [Thu, 5 Apr 2018 23:22:43 +0000 (16:22 -0700)]
x86/mm/memory_hotplug: determine block size based on the end of boot memory

Memory sections are combined into "memory block" chunks.  These chunks
are the units upon which memory can be added and removed.

On x86, the new memory may be added after the end of the boot memory,
therefore, if block size does not align with end of boot memory, memory
hot-plugging/hot-removing can be broken.

Memory sections are combined into "memory block" chunks.  These chunks
are the units upon which memory can be added and removed.

On x86 the new memory may be added after the end of the boot memory,
therefore, if block size does not align with end of boot memory, memory
hotplugging/hotremoving can be broken.

Currently, whenever machine is booted with more than 64G the block size
is unconditionally increased to 2G from the base 128M.  This is done in
order to reduce number of memory device files in sysfs:

/sys/devices/system/memory/memoryXXX

We must use the largest allowed block size that aligns to the next
address to be able to hotplug the next block of memory.

So, when memory is larger or equal to 64G, we check the end address and
find the largest block size that is still power of two but smaller or
equal to 2G.

Before, the fix:
Run qemu with:
-m 64G,slots=2,maxmem=66G -object memory-backend-ram,id=mem1,size=2G

(qemu) device_add pc-dimm,id=dimm1,memdev=mem1
Block size [0x80000000] unaligned hotplug range: start 0x1040000000,
size 0x80000000
acpi PNP0C80:00: add_memory failed
acpi PNP0C80:00: acpi_memory_enable_device() error
acpi PNP0C80:00: Enumeration failure

With the fix memory is added successfully as the block size is set to
1G, and therefore aligns with start address 0x1040000000.

[pasha.tatashin@oracle.com: v4]
Link: http://lkml.kernel.org/r/20180215165920.8570-3-pasha.tatashin@oracle.com
Link: http://lkml.kernel.org/r/20180213193159.14606-3-pasha.tatashin@oracle.com
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Bharata B Rao <bharata@linux.vnet.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm/memory_hotplug: enforce block size aligned range check
Pavel Tatashin [Thu, 5 Apr 2018 23:22:39 +0000 (16:22 -0700)]
mm/memory_hotplug: enforce block size aligned range check

Patch series "optimize memory hotplug", v3.

This patchset:

 - Improves hotplug performance by eliminating a number of struct page
   traverses during memory hotplug.

 - Fixes some issues with hotplugging, where boundaries were not
   properly checked. And on x86 block size was not properly aligned with
   end of memory

 - Also, potentially improves boot performance by eliminating condition
   from __init_single_page().

 - Adds robustness by verifying that that struct pages are correctly
   poisoned when flags are accessed.

The following experiments were performed on Xeon(R) CPU E7-8895 v3 @
2.60GHz with 1T RAM:

booting in qemu with 960G of memory, time to initialize struct pages:

no-kvm:
TRY1 TRY2
BEFORE: 39.433668 39.39705
AFTER: 36.903781 36.989329

with-kvm:
BEFORE: 10.977447 11.103164
AFTER: 10.929072 10.751885

Hotplug 896G memory:
no-kvm:
TRY1 TRY2
BEFORE: 848.740000 846.910000
AFTER:  783.070000 786.560000

with-kvm:
TRY1 TRY2
BEFORE: 34.410000 33.57
AFTER: 29.810000 29.580000

This patch (of 6):

Start qemu with the following arguments:

  -m 64G,slots=2,maxmem=66G -object memory-backend-ram,id=mem1,size=2G

Which: boots machine with 64G, and adds a device mem1 with 2G which can
be hotplugged later.

Also make sure that config has the following turned on:
  CONFIG_MEMORY_HOTPLUG
  CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE
  CONFIG_ACPI_HOTPLUG_MEMORY

Using the qemu monitor hotplug the memory (make sure config has (qemu)
device_add pc-dimm,id=dimm1,memdev=mem1

The operation will fail with the following trace:

    WARNING: CPU: 0 PID: 91 at drivers/base/memory.c:205
    pages_correctly_reserved+0xe6/0x110
    Modules linked in:
    CPU: 0 PID: 91 Comm: systemd-udevd Not tainted 4.16.0-rc1_pt_master #29
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
    BIOS rel-1.11.0-0-g63451fca13-prebuilt.qemu-project.org 04/01/2014
    RIP: 0010:pages_correctly_reserved+0xe6/0x110
    Call Trace:
     memory_subsys_online+0x44/0xa0
     device_online+0x51/0x80
     store_mem_state+0x5e/0xe0
     kernfs_fop_write+0xfa/0x170
     __vfs_write+0x2e/0x150
     vfs_write+0xa8/0x1a0
     SyS_write+0x4d/0xb0
     do_syscall_64+0x5d/0x110
     entry_SYSCALL_64_after_hwframe+0x21/0x86
    ---[ end trace 6203bc4f1a5d30e8 ]---

The problem is detected in: drivers/base/memory.c

   static bool pages_correctly_reserved(unsigned long start_pfn)
   205                 if (WARN_ON_ONCE(!pfn_valid(pfn)))

This function loops through every section in the newly added memory
block and verifies that the first pfn is valid, meaning section exists,
has mapping (struct page array), and is online.

The block size on x86 is usually 128M, but when machine is booted with
more than 64G of memory, the block size is changed to 2G: $ cat
/sys/devices/system/memory/block_size_bytes 80000000

or

   $ dmesg | grep "block size"
   [    0.086469] x86/mm: Memory block size: 2048MB

During memory hotplug, and hotremove we verify that the range is section
size aligned, but we actually must verify that it is block size aligned,
because that is the proper unit for hotplug operations.  See:
Documentation/memory-hotplug.txt

So, when the start_pfn of newly added memory is not block size aligned,
we can get a memory block that has only part of it with properly
populated sections.

In our case the start_pfn starts from the last_pfn (end of physical
memory).

   $ dmesg | grep last_pfn
   [    0.000000] e820: last_pfn = 0x1040000 max_arch_pfn = 0x400000000

0x1040000 == 65G, and so is not 2G aligned!

The fix is to enforce that memory that is hotplugged and hotremoved is
block size aligned.

With this fix, running the above sequence yield to the following result:

   (qemu) device_add pc-dimm,id=dimm1,memdev=mem1
   Block size [0x80000000] unaligned hotplug range: start 0x1040000000,
    size 0x80000000
   acpi PNP0C80:00: add_memory failed
   acpi PNP0C80:00: acpi_memory_enable_device() error
   acpi PNP0C80:00: Enumeration failure

Link: http://lkml.kernel.org/r/20180213193159.14606-2-pasha.tatashin@oracle.com
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Bharata B Rao <bharata@linux.vnet.ibm.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm: thp: fix potential clearing to referenced flag in page_idle_clear_pte_refs_one()
Yang Shi [Thu, 5 Apr 2018 23:22:35 +0000 (16:22 -0700)]
mm: thp: fix potential clearing to referenced flag in page_idle_clear_pte_refs_one()

For PTE-mapped THP, the compound THP has not been split to normal 4K
pages yet, the whole THP is considered referenced if any one of sub page
is referenced.

When walking PTE-mapped THP by pvmw, all relevant PTEs will be checked
to retrieve referenced bit.  But, the current code just returns the
result of the last PTE.  If the last PTE has not referenced, the
referenced flag will be cleared.

Just set referenced when ptep{pmdp}_clear_young_notify() returns true.

Link: http://lkml.kernel.org/r/1518212451-87134-1-git-send-email-yang.shi@linux.alibaba.com
Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
Reported-by: Gang Deng <gavin.dg@linux.alibaba.com>
Suggested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm: initialize pages on demand during boot
Pavel Tatashin [Thu, 5 Apr 2018 23:22:31 +0000 (16:22 -0700)]
mm: initialize pages on demand during boot

Deferred page initialization allows the boot cpu to initialize a small
subset of the system's pages early in boot, with other cpus doing the
rest later on.

It is, however, problematic to know how many pages the kernel needs
during boot.  Different modules and kernel parameters may change the
requirement, so the boot cpu either initializes too many pages or runs
out of memory.

To fix that, initialize early pages on demand.  This ensures the kernel
does the minimum amount of work to initialize pages during boot and
leaves the rest to be divided in the multithreaded initialization path
(deferred_init_memmap).

The on-demand code is permanently disabled using static branching once
deferred pages are initialized.  After the static branch is changed to
false, the overhead is up-to two branch-always instructions if the zone
watermark check fails or if rmqueue fails.

Sergey Senozhatsky noticed that while deferred pages currently make
sense only on NUMA machines (we start one thread per latency node),
CONFIG_NUMA is not a requirement for CONFIG_DEFERRED_STRUCT_PAGE_INIT,
so that is also must be addressed in the patch.

[akpm@linux-foundation.org: fix typo in comment, make deferred_pages static]
[pasha.tatashin@oracle.com: fix min() type mismatch warning]
Link: http://lkml.kernel.org/r/20180212164543.26592-1-pasha.tatashin@oracle.com
[pasha.tatashin@oracle.com: use zone_to_nid() in deferred_grow_zone()]
Link: http://lkml.kernel.org/r/20180214163343.21234-2-pasha.tatashin@oracle.com
[pasha.tatashin@oracle.com: might_sleep warning]
Link: http://lkml.kernel.org/r/20180306192022.28289-1-pasha.tatashin@oracle.com
[akpm@linux-foundation.org: s/spin_lock/spin_lock_irq/ in page_alloc_init_late()]
[pasha.tatashin@oracle.com: v5]
Link: http://lkml.kernel.org/r/20180309220807.24961-3-pasha.tatashin@oracle.com
[akpm@linux-foundation.org: tweak comments]
[pasha.tatashin@oracle.com: v6]
Link: http://lkml.kernel.org/r/20180313182355.17669-3-pasha.tatashin@oracle.com
[akpm@linux-foundation.org: coding-style fixes]
Link: http://lkml.kernel.org/r/20180209192216.20509-2-pasha.tatashin@oracle.com
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Reviewed-by: Steven Sistare <steven.sistare@oracle.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Gioh Kim <gi-oh.kim@profitbricks.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Miles Chen <miles.chen@mediatek.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm: disable interrupts while initializing deferred pages
Pavel Tatashin [Thu, 5 Apr 2018 23:22:27 +0000 (16:22 -0700)]
mm: disable interrupts while initializing deferred pages

Vlastimil Babka reported about a window issue during which when deferred
pages are initialized, and the current version of on-demand
initialization is finished, allocations may fail.  While this is highly
unlikely scenario, since this kind of allocation request must be large,
and must come from interrupt handler, we still want to cover it.

We solve this by initializing deferred pages with interrupts disabled,
and holding node_size_lock spin lock while pages in the node are being
initialized.  The on-demand deferred page initialization that comes
later will use the same lock, and thus synchronize with
deferred_init_memmap().

It is unlikely for threads that initialize deferred pages to be
interrupted.  They run soon after smp_init(), but before modules are
initialized, and long before user space programs.  This is why there is
no adverse effect of having these threads running with interrupts
disabled.

[pasha.tatashin@oracle.com: v6]
Link: http://lkml.kernel.org/r/20180313182355.17669-2-pasha.tatashin@oracle.com
Link: http://lkml.kernel.org/r/20180309220807.24961-2-pasha.tatashin@oracle.com
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Gioh Kim <gi-oh.kim@profitbricks.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Miles Chen <miles.chen@mediatek.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm/swap_slots.c: use conditional compilation
Randy Dunlap [Thu, 5 Apr 2018 23:22:23 +0000 (16:22 -0700)]
mm/swap_slots.c: use conditional compilation

For mm/swap_slots.c, use the traditional Linux method of conditional
compilation and linking instead of always compiling it by using #ifdef
CONFIG_SWAP and #endif for the entire source file (excluding header
files).

Link: http://lkml.kernel.org/r/c2a47015-0b5a-d0d9-8bc7-9984c049df20@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Tim Chen <tim.c.chen@linux.intel.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm/migrate: rename migration reason MR_CMA to MR_CONTIG_RANGE
Anshuman Khandual [Thu, 5 Apr 2018 23:22:08 +0000 (16:22 -0700)]
mm/migrate: rename migration reason MR_CMA to MR_CONTIG_RANGE

alloc_contig_range() initiates compaction and eventual migration for the
purpose of either CMA or HugeTLB allocations.  At present, the reason
code remains the same MR_CMA for either of these cases.  Let's make it
MR_CONTIG_RANGE which will appropriately reflect the reason code in both
these cases.

Link: http://lkml.kernel.org/r/20180202091518.18798-1-khandual@linux.vnet.ibm.com
Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm: always print RLIMIT_DATA warning
David Woodhouse [Thu, 5 Apr 2018 23:22:05 +0000 (16:22 -0700)]
mm: always print RLIMIT_DATA warning

The documentation for ignore_rlimit_data says that it will print a
warning at first misuse.  Yet it doesn't seem to do that.

Fix the code to print the warning even when we allow the process to
continue.

Link: http://lkml.kernel.org/r/1517935505-9321-1-git-send-email-dwmw@amazon.co.uk
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Acked-by: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm/ksm.c: make stable_node_dup() static
Colin Ian King [Thu, 5 Apr 2018 23:22:01 +0000 (16:22 -0700)]
mm/ksm.c: make stable_node_dup() static

stable_node_dup() is local to the source and does not need to be in
global scope, so make it static.

Cleans up sparse warning:

  mm/ksm.c:1321:13: warning: symbol 'stable_node_dup' was not declared. Should it be static?

Link: http://lkml.kernel.org/r/20180206221005.12642-1-colin.king@canonical.com
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoslab, slub: skip unnecessary kasan_cache_shutdown()
Shakeel Butt [Thu, 5 Apr 2018 23:21:57 +0000 (16:21 -0700)]
slab, slub: skip unnecessary kasan_cache_shutdown()

The kasan quarantine is designed to delay freeing slab objects to catch
use-after-free.  The quarantine can be large (several percent of machine
memory size).  When kmem_caches are deleted related objects are flushed
from the quarantine but this requires scanning the entire quarantine
which can be very slow.  We have seen the kernel busily working on this
while holding slab_mutex and badly affecting cache_reaper, slabinfo
readers and memcg kmem cache creations.

It can easily reproduced by following script:

yes . | head -1000000 | xargs stat > /dev/null
for i in `seq 1 10`; do
seq 500 | (cd /cg/memory && xargs mkdir)
seq 500 | xargs -I{} sh -c 'echo $BASHPID > \
/cg/memory/{}/tasks && exec stat .' > /dev/null
seq 500 | (cd /cg/memory && xargs rmdir)
done

The busy stack:
    kasan_cache_shutdown
    shutdown_cache
    memcg_destroy_kmem_caches
    mem_cgroup_css_free
    css_free_rwork_fn
    process_one_work
    worker_thread
    kthread
    ret_from_fork

This patch is based on the observation that if the kmem_cache to be
destroyed is empty then there should not be any objects of this cache in
the quarantine.

Without the patch the script got stuck for couple of hours.  With the
patch the script completed within a second.

Link: http://lkml.kernel.org/r/20180327230603.54721-1-shakeelb@google.com
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agomm/slab_common.c: remove test if cache name is accessible
Mikulas Patocka [Thu, 5 Apr 2018 23:21:53 +0000 (16:21 -0700)]
mm/slab_common.c: remove test if cache name is accessible

Since commit db265eca7700 ("mm/sl[aou]b: Move duping of slab name to
slab_common.c"), the kernel always duplicates the slab cache name when
creating a slab cache, so the test if the slab name is accessible is
useless.

Link: http://lkml.kernel.org/r/alpine.LRH.2.02.1803231133310.22626@file01.intranet.prod.int.rdu2.redhat.com
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoslab, slub: remove size disparity on debug kernel
Shakeel Butt [Thu, 5 Apr 2018 23:21:50 +0000 (16:21 -0700)]
slab, slub: remove size disparity on debug kernel

I have noticed on debug kernel with SLAB, the size of some non-root
slabs were larger than their corresponding root slabs.

e.g. for radix_tree_node:
  $cat /proc/slabinfo | grep radix
  name     <active_objs> <num_objs> <objsize> <objperslab> <pagesperslab> ...
  radix_tree_node 15052    15075      4096         1             1 ...

  $cat /cgroup/memory/temp/memory.kmem.slabinfo | grep radix
  name     <active_objs> <num_objs> <objsize> <objperslab> <pagesperslab> ...
  radix_tree_node 1581      158       4120         1             2 ...

However for SLUB in debug kernel, the sizes were same.  On further
inspection it is found that SLUB always use kmem_cache.object_size to
measure the kmem_cache.size while SLAB use the given kmem_cache.size.
In the debug kernel the slab's size can be larger than its object_size.
Thus in the creation of non-root slab, the SLAB uses the root's size as
base to calculate the non-root slab's size and thus non-root slab's size
can be larger than the root slab's size.  For SLUB, the non-root slab's
size is measured based on the root's object_size and thus the size will
remain same for root and non-root slab.

This patch makes slab's object_size the default base to measure the
slab's size.

Link: http://lkml.kernel.org/r/20180313165428.58699-1-shakeelb@google.com
Fixes: 794b1248be4e ("memcg, slab: separate memcg vs root cache creation paths")
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoslab: use 32-bit arithmetic in freelist_randomize()
Alexey Dobriyan [Thu, 5 Apr 2018 23:21:46 +0000 (16:21 -0700)]
slab: use 32-bit arithmetic in freelist_randomize()

SLAB doesn't support 4GB+ of objects per slab, therefore randomization
doesn't need size_t.

Link: http://lkml.kernel.org/r/20180305200730.15812-25-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoslub: make size_from_object() return unsigned int
Alexey Dobriyan [Thu, 5 Apr 2018 23:21:43 +0000 (16:21 -0700)]
slub: make size_from_object() return unsigned int

Function returns size of the object without red zone which can't be
negative.

Link: http://lkml.kernel.org/r/20180305200730.15812-24-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoslub: make struct kmem_cache_order_objects::x unsigned int
Alexey Dobriyan [Thu, 5 Apr 2018 23:21:39 +0000 (16:21 -0700)]
slub: make struct kmem_cache_order_objects::x unsigned int

struct kmem_cache_order_objects is for mixing order and number of
objects, and orders aren't big enough to warrant 64-bit width.

Propagate unsignedness down so that everything fits.

!!! Patch assumes that "PAGE_SIZE << order" doesn't overflow. !!!

Link: http://lkml.kernel.org/r/20180305200730.15812-23-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoslub: make slab_index() return unsigned int
Alexey Dobriyan [Thu, 5 Apr 2018 23:21:35 +0000 (16:21 -0700)]
slub: make slab_index() return unsigned int

slab_index() returns index of an object within a slab which is at most
u15 (or u16?).

Iterators additionally guarantee that "p >= addr".

Link: http://lkml.kernel.org/r/20180305200730.15812-22-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoslab: make usercopy region 32-bit
Alexey Dobriyan [Thu, 5 Apr 2018 23:21:31 +0000 (16:21 -0700)]
slab: make usercopy region 32-bit

If kmem case sizes are 32-bit, then usecopy region should be too.

Link: http://lkml.kernel.org/r/20180305200730.15812-21-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: David Miller <davem@davemloft.net>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agokasan: make kasan_cache_create() work with 32-bit slab cache sizes
Alexey Dobriyan [Thu, 5 Apr 2018 23:21:28 +0000 (16:21 -0700)]
kasan: make kasan_cache_create() work with 32-bit slab cache sizes

If SLAB doesn't support 4GB+ kmem caches (it never did), KASAN should
not do it as well.

Link: http://lkml.kernel.org/r/20180305200730.15812-20-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoslab: make kmem_cache_flags accept 32-bit object size
Alexey Dobriyan [Thu, 5 Apr 2018 23:21:24 +0000 (16:21 -0700)]
slab: make kmem_cache_flags accept 32-bit object size

Now that all sizes are properly typed, propagate "unsigned int" down the
callgraph.

Link: http://lkml.kernel.org/r/20180305200730.15812-19-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoslub: make ->size unsigned int
Alexey Dobriyan [Thu, 5 Apr 2018 23:21:20 +0000 (16:21 -0700)]
slub: make ->size unsigned int

Linux doesn't support negative length objects (including meta data).

Link: http://lkml.kernel.org/r/20180305200730.15812-18-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoslub: make ->object_size unsigned int
Alexey Dobriyan [Thu, 5 Apr 2018 23:21:17 +0000 (16:21 -0700)]
slub: make ->object_size unsigned int

Linux doesn't support negative length objects.

Link: http://lkml.kernel.org/r/20180305200730.15812-17-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoslub: make ->offset unsigned int
Alexey Dobriyan [Thu, 5 Apr 2018 23:21:13 +0000 (16:21 -0700)]
slub: make ->offset unsigned int

->offset is free pointer offset from the start of the object, can't be
negative.

Link: http://lkml.kernel.org/r/20180305200730.15812-16-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoslub: make ->cpu_partial unsigned int
Alexey Dobriyan [Thu, 5 Apr 2018 23:21:10 +0000 (16:21 -0700)]
slub: make ->cpu_partial unsigned int

/*
 * cpu_partial determined the maximum number of objects
 * kept in the per cpu partial lists of a processor.
 */

Can't be negative.

Link: http://lkml.kernel.org/r/20180305200730.15812-15-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoslub: make ->inuse unsigned int
Alexey Dobriyan [Thu, 5 Apr 2018 23:21:06 +0000 (16:21 -0700)]
slub: make ->inuse unsigned int

->inuse is "the number of bytes in actual use by the object",
can't be negative.

Link: http://lkml.kernel.org/r/20180305200730.15812-14-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoslub: make ->align unsigned int
Alexey Dobriyan [Thu, 5 Apr 2018 23:21:02 +0000 (16:21 -0700)]
slub: make ->align unsigned int

Kmem cache alignment can't be negative.

Link: http://lkml.kernel.org/r/20180305200730.15812-13-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoslub: make ->reserved unsigned int
Alexey Dobriyan [Thu, 5 Apr 2018 23:20:58 +0000 (16:20 -0700)]
slub: make ->reserved unsigned int

->reserved is either 0 or sizeof(struct rcu_head), can't be negative.

Link: http://lkml.kernel.org/r/20180305200730.15812-12-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoslub: make ->red_left_pad unsigned int
Alexey Dobriyan [Thu, 5 Apr 2018 23:20:55 +0000 (16:20 -0700)]
slub: make ->red_left_pad unsigned int

Padding length can't be negative.

Link: http://lkml.kernel.org/r/20180305200730.15812-11-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoslub: make ->max_attr_size unsigned int
Alexey Dobriyan [Thu, 5 Apr 2018 23:20:51 +0000 (16:20 -0700)]
slub: make ->max_attr_size unsigned int

->max_attr_size is maximum length of every SLAB memcg attribute
ever written. VFS limits those to INT_MAX.

Link: http://lkml.kernel.org/r/20180305200730.15812-10-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoslub: make ->remote_node_defrag_ratio unsigned int
Alexey Dobriyan [Thu, 5 Apr 2018 23:20:48 +0000 (16:20 -0700)]
slub: make ->remote_node_defrag_ratio unsigned int

->remote_node_defrag_ratio is in range 0..1000.

This also adds a check and modifies the behavior to return an error
code.  Before this patch invalid values were ignored.

Link: http://lkml.kernel.org/r/20180305200730.15812-9-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoslab: make size_index_elem() unsigned int
Alexey Dobriyan [Thu, 5 Apr 2018 23:20:44 +0000 (16:20 -0700)]
slab: make size_index_elem() unsigned int

size_index_elem() always works with small sizes (kmalloc caches are
32-bit) and returns small indexes.

Link: http://lkml.kernel.org/r/20180305200730.15812-8-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoslab: make size_index[] array u8
Alexey Dobriyan [Thu, 5 Apr 2018 23:20:40 +0000 (16:20 -0700)]
slab: make size_index[] array u8

All those small numbers are reverse indexes into kmalloc caches array
and can't be negative.

On x86_64 "unsigned int = fls()" can drop CDQE instruction:

add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-2 (-2)
Function                                     old     new   delta
kmalloc_slab                                 101      99      -2

Link: http://lkml.kernel.org/r/20180305200730.15812-7-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoslab: make kmem_cache_create() work with 32-bit sizes
Alexey Dobriyan [Thu, 5 Apr 2018 23:20:37 +0000 (16:20 -0700)]
slab: make kmem_cache_create() work with 32-bit sizes

struct kmem_cache::size and ::align were always 32-bit.

Out of curiosity I created 4GB kmem_cache, it oopsed with division by 0.
kmem_cache_create(1UL<<32+1) created 1-byte cache as expected.

size_t doesn't work and never did.

Link: http://lkml.kernel.org/r/20180305200730.15812-6-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoslab: make create_boot_cache() work with 32-bit sizes
Alexey Dobriyan [Thu, 5 Apr 2018 23:20:33 +0000 (16:20 -0700)]
slab: make create_boot_cache() work with 32-bit sizes

struct kmem_cache::size has always been "int", all those
"size_t size" are fake.

Link: http://lkml.kernel.org/r/20180305200730.15812-5-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoslab: make create_kmalloc_cache() work with 32-bit sizes
Alexey Dobriyan [Thu, 5 Apr 2018 23:20:29 +0000 (16:20 -0700)]
slab: make create_kmalloc_cache() work with 32-bit sizes

KMALLOC_MAX_CACHE_SIZE is 32-bit so is the largest kmalloc cache size.

Christoph said:
:
: Ok SLABs maximum allocation size is limited to 32M (see
: include/linux/slab.h:
:
: #define KMALLOC_SHIFT_HIGH      ((MAX_ORDER + PAGE_SHIFT - 1) <= 25 ? \
:                                 (MAX_ORDER + PAGE_SHIFT - 1) : 25)
:
: And SLUB/SLOB pass all larger requests to the page allocator anyways.

Link: http://lkml.kernel.org/r/20180305200730.15812-4-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoslab: make kmalloc_size() return "unsigned int"
Alexey Dobriyan [Thu, 5 Apr 2018 23:20:26 +0000 (16:20 -0700)]
slab: make kmalloc_size() return "unsigned int"

kmalloc_size() derives size of kmalloc cache from internal index, which
can't be negative.

Propagate unsignedness a bit.

Link: http://lkml.kernel.org/r/20180305200730.15812-3-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoslab: make kmalloc_index() return "unsigned int"
Alexey Dobriyan [Thu, 5 Apr 2018 23:20:22 +0000 (16:20 -0700)]
slab: make kmalloc_index() return "unsigned int"

kmalloc_index() return index into an array of kmalloc kmem caches,
therefore should be unsigned.

Space savings with SLUB on trimmed down .config:

add/remove: 0/1 grow/shrink: 6/56 up/down: 85/-557 (-472)
Function                                     old     new   delta
calculate_sizes                              924     983     +59
on_freelist                                  589     604     +15
init_cache_random_seq                        122     127      +5
ext4_mb_init                                1206    1210      +4
slab_pad_check.part                          270     271      +1
cpu_partial_store                            112     113      +1
usersize_show                                 28      27      -1
...
new_slab                                    1871    1837     -34
slab_order                                   204       -    -204

This patch start a series of converting SLUB (mostly) to "unsigned int".

1) Most integers in the code are in fact unsigned entities: array
   indexes, lengths, buffer sizes, allocation orders. It is therefore
   better to use unsigned variables

2) Some integers in the code are either "size_t" or "unsigned long" for
   no reason.

   size_t usually comes from people trying to maintain type correctness
   and figuring out that "sizeof" operator returns size_t or
   memset/memcpy takes size_t so should everything passed to it.

   However the number of 4GB+ objects in the kernel is very small. Most,
   if not all, dynamically allocated objects with kmalloc() or
   kmem_cache_create() aren't actually big. Maintaining wide types
   doesn't do anything.

   64-bit ops are bigger than 32-bit on our beloved x86_64,
   so try to not use 64-bit where it isn't necessary
   (read: everywhere where integers are integers not pointers)

3) in case of SLAB allocators, there are additional limitations
   *) page->inuse, page->objects are only 16-/15-bit,
   *) cache size was always 32-bit
   *) slab orders are small, order 20 is needed to go 64-bit on x86_64
      (PAGE_SIZE << order)

Basically everything is 32-bit except kmalloc(1ULL<<32) which gets
shortcut through page allocator.

Christoph said:
:
: That changes with large base page size on power and ARM64 f.e. but then
: we do not want to encourage larger allocations through slab anyways.

Link: http://lkml.kernel.org/r/20180305200730.15812-2-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>