git.samba.org - sfrench/cifs-2.6.git/atom - Documentation/admin-guide/kernel-parameters.txt history Unnamed repository; edit this file 'description' to name the repository. http://git.samba.org/samba.git/?p=sfrench/cifs-2.6.git Steve French //www.samba.org/samba/style/2010/grey/favicon.ico //www.samba.org/samba/style/2010/samba_2010_logo_transparent_151x27.png 2024-03-18T22:11:44Z gitweb Merge tag 'trace-v6.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux... 2024-03-18T22:11:44Z Linus Torvalds torvalds@linux-foundation.org Linus Torvalds torvalds@linux-foundation.org 2024-03-18T22:11:44Z http://git.samba.org/samba.git/?p=sfrench/cifs-2.6.git;a=commitdiff;h=ad584d73a22b2f6e6b4c928956fdece5c44cdb3e
Merge tag 'trace-v6.9-2' of git://git./linux/kernel/git/trace/linux-trace

Pull tracing updates from Steven Rostedt:
 "Main user visible change:

   - User events can now have "multi formats"

     The current user events have a single format. If another event is
     created with a different format, it will fail to be created. That
     is, once an event name is used, it cannot be used again with a
     different format. This can cause issues if a library is using an
     event and updates its format. An application using the older format
     will prevent an application using the new library from registering
     its event.

     A task could also DOS another application if it knows the event
     names, and it creates events with different formats.

     The multi-format event is in a different name space from the single
     format. Both the event name and its format are the unique
     identifier. This will allow two different applications to use the
     same user event name but with different payloads.

   - Added support to have ftrace_dump_on_oops dump out instances and
     not just the main top level tracing buffer.

  Other changes:

   - Add eventfs_root_inode

     Only the root inode has a dentry that is static (never goes away)
     and stores it upon creation. There's no reason that the thousands
     of other eventfs inodes should have a pointer that never gets set
     in its descriptor. Create a eventfs_root_inode desciptor that has a
     eventfs_inode descriptor and a dentry pointer, and only the root
     inode will use this.

   - Added WARN_ON()s in eventfs

     There's some conditionals remaining in eventfs that should never be
     hit, but instead of removing them, add WARN_ON() around them to
     make sure that they are never hit.

   - Have saved_cmdlines allocation also include the map_cmdline_to_pid
     array

     The saved_cmdlines structure allocates a large amount of data to
     hold its mappings. Within it, it has three arrays. Two are already
     apart of it: map_pid_to_cmdline[] and saved_cmdlines[]. More memory
     can be saved by also including the map_cmdline_to_pid[] array as
     well.

   - Restructure __string() and __assign_str() macros used in
     TRACE_EVENT()

     Dynamic strings in TRACE_EVENT() are declared with:

         __string(name, source)

     And assigned with:

        __assign_str(name, source)

     In the tracepoint callback of the event, the __string() is used to
     get the size needed to allocate on the ring buffer and
     __assign_str() is used to copy the string into the ring buffer.
     There's a helper structure that is created in the TRACE_EVENT()
     macro logic that will hold the string length and its position in
     the ring buffer which is created by __string().

     There are several trace events that have a function to create the
     string to save. This function is executed twice. Once for
     __string() and again for __assign_str(). There's no reason for
     this. The helper structure could also save the string it used in
     __string() and simply copy that into __assign_str() (it also
     already has its length).

     By using the structure to store the source string for the
     assignment, it means that the second argument to __assign_str() is
     no longer needed.

     It will be removed in the next merge window, but for now add a
     warning if the source string given to __string() is different than
     the source string given to __assign_str(), as the source to
     __assign_str() isn't even used and will be going away.

   - Added checks to make sure that the source of __string() is also the
     source of __assign_str() so that it can be safely removed in the
     next merge window.

     Included fixes that the above check found.

   - Other minor clean ups and fixes"

* tag 'trace-v6.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (34 commits)
  tracing: Add __string_src() helper to help compilers not to get confused
  tracing: Use strcmp() in __assign_str() WARN_ON() check
  tracepoints: Use WARN() and not WARN_ON() for warnings
  tracing: Use div64_u64() instead of do_div()
  tracing: Support to dump instance traces by ftrace_dump_on_oops
  tracing: Remove second parameter to __assign_rel_str()
  tracing: Add warning if string in __assign_str() does not match __string()
  tracing: Add __string_len() example
  tracing: Remove __assign_str_len()
  ftrace: Fix most kernel-doc warnings
  tracing: Decrement the snapshot if the snapshot trigger fails to register
  tracing: Fix snapshot counter going between two tracers that use it
  tracing: Use EVENT_NULL_STR macro instead of open coding "(null)"
  tracing: Use ? : shortcut in trace macros
  tracing: Do not calculate strlen() twice for __string() fields
  tracing: Rework __assign_str() and __string() to not duplicate getting the string
  cxl/trace: Properly initialize cxl_poison region name
  net: hns3: tracing: fix hclgevf trace event strings
  drm/i915: Add missing ; to __assign_str() macros in tracepoint code
  NFSD: Fix nfsd_clid_class use of __string_len() macro
  ...
  • [D] Documentation/admin-guide/kernel-parameters.txt
tracing: Support to dump instance traces by ftrace_dump_on_oops 2024-02-23T08:31:26Z Huang Yiwei quic_hyiwei@quicinc.com Steven Rostedt (Google) rostedt@goodmis.org 2024-02-23T08:31:26Z http://git.samba.org/samba.git/?p=sfrench/cifs-2.6.git;a=commitdiff;h=19f0423fd55c301c8edaea286e568ec657f42750
tracing: Support to dump instance traces by ftrace_dump_on_oops

Currently ftrace only dumps the global trace buffer on an OOPs. For
debugging a production usecase, instance trace will be helpful to
check specific problems since global trace buffer may be used for
other purposes.

This patch extend the ftrace_dump_on_oops parameter to dump a specific
or multiple trace instances:

  - ftrace_dump_on_oops=0: as before -- don't dump
  - ftrace_dump_on_oops[=1]: as before -- dump the global trace buffer
  on all CPUs
  - ftrace_dump_on_oops=2 or =orig_cpu: as before -- dump the global
  trace buffer on CPU that triggered the oops
  - ftrace_dump_on_oops=<instance_name>: new behavior -- dump the
  tracing instance matching <instance_name>
  - ftrace_dump_on_oops[=2/orig_cpu],<instance1_name>[=2/orig_cpu],
  <instrance2_name>[=2/orig_cpu]: new behavior -- dump the global trace
  buffer and multiple instance buffer on all CPUs, or only dump on CPU
  that triggered the oops if =2 or =orig_cpu is given

Also, the sysctl node can handle the input accordingly.

Link: https://lore.kernel.org/linux-trace-kernel/20240223083126.1817731-1-quic_hyiwei@quicinc.com

Cc: Ross Zwisler <zwisler@google.com>
Cc: <mhiramat@kernel.org>
Cc: <mark.rutland@arm.com>
Cc: <mcgrof@kernel.org>
Cc: <keescook@chromium.org>
Cc: <j.granados@samsung.com>
Cc: <mathieu.desnoyers@efficios.com>
Cc: <corbet@lwn.net>
Signed-off-by: Huang Yiwei <quic_hyiwei@quicinc.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
  • [D] Documentation/admin-guide/kernel-parameters.txt
Merge tag 'mm-nonmm-stable-2024-03-14-09-36' of git://git.kernel.org/pub/scm/linux... 2024-03-15T01:03:09Z Linus Torvalds torvalds@linux-foundation.org Linus Torvalds torvalds@linux-foundation.org 2024-03-15T01:03:09Z http://git.samba.org/samba.git/?p=sfrench/cifs-2.6.git;a=commitdiff;h=e5eb28f6d1afebed4bb7d740a797d0390bd3a357
Merge tag 'mm-nonmm-stable-2024-03-14-09-36' of git://git./linux/kernel/git/akpm/mm

Pull non-MM updates from Andrew Morton:

 - Kuan-Wei Chiu has developed the well-named series "lib min_heap: Min
   heap optimizations".

 - Kuan-Wei Chiu has also sped up the library sorting code in the series
   "lib/sort: Optimize the number of swaps and comparisons".

 - Alexey Gladkov has added the ability for code running within an IPC
   namespace to alter its IPC and MQ limits. The series is "Allow to
   change ipc/mq sysctls inside ipc namespace".

 - Geert Uytterhoeven has contributed some dhrystone maintenance work in
   the series "lib: dhry: miscellaneous cleanups".

 - Ryusuke Konishi continues nilfs2 maintenance work in the series

	"nilfs2: eliminate kmap and kmap_atomic calls"
	"nilfs2: fix kernel bug at submit_bh_wbc()"

 - Nathan Chancellor has updated our build tools requirements in the
   series "Bump the minimum supported version of LLVM to 13.0.1".

 - Muhammad Usama Anjum continues with the selftests maintenance work in
   the series "selftests/mm: Improve run_vmtests.sh".

 - Oleg Nesterov has done some maintenance work against the signal code
   in the series "get_signal: minor cleanups and fix".

Plus the usual shower of singleton patches in various parts of the tree.
Please see the individual changelogs for details.

* tag 'mm-nonmm-stable-2024-03-14-09-36' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (77 commits)
  nilfs2: prevent kernel bug at submit_bh_wbc()
  nilfs2: fix failure to detect DAT corruption in btree and direct mappings
  ocfs2: enable ocfs2_listxattr for special files
  ocfs2: remove SLAB_MEM_SPREAD flag usage
  assoc_array: fix the return value in assoc_array_insert_mid_shortcut()
  buildid: use kmap_local_page()
  watchdog/core: remove sysctl handlers from public header
  nilfs2: use div64_ul() instead of do_div()
  mul_u64_u64_div_u64: increase precision by conditionally swapping a and b
  kexec: copy only happens before uchunk goes to zero
  get_signal: don't initialize ksig->info if SIGNAL_GROUP_EXIT/group_exec_task
  get_signal: hide_si_addr_tag_bits: fix the usage of uninitialized ksig
  get_signal: don't abuse ksig->info.si_signo and ksig->sig
  const_structs.checkpatch: add device_type
  Normalise "name (ad@dr)" MODULE_AUTHORs to "name <ad@dr>"
  dyndbg: replace kstrdup() + strchr() with kstrdup_and_replace()
  list: leverage list_is_head() for list_entry_is_head()
  nilfs2: MAINTAINERS: drop unreachable project mirror site
  smp: make __smp_processor_id() 0-argument macro
  fat: fix uninitialized field in nostale filehandles
  ...
  • [D] Documentation/admin-guide/kernel-parameters.txt
Merge tag 'drm-next-2024-03-13' of https://gitlab.freedesktop.org/drm/kernel 2024-03-14T01:34:05Z Linus Torvalds torvalds@linux-foundation.org Linus Torvalds torvalds@linux-foundation.org 2024-03-14T01:34:05Z http://git.samba.org/samba.git/?p=sfrench/cifs-2.6.git;a=commitdiff;h=480e035fc4c714fb5536e64ab9db04fedc89e910
Merge tag 'drm-next-2024-03-13' of https://gitlab.freedesktop.org/drm/kernel

Pull drm updates from Dave Airlie:
 "Highlights are usual, more AMD IP blocks for future hw, i915/xe
  changes, Displayport tunnelling support for i915, msm YUV over DP
  changes, new tests for ttm, but its mostly a lot of stuff all over the
  place from lots of people.

  core:
   - EDID cleanups
   - scheduler error handling fixes
   - managed: add drmm_release_action() with tests
   - add ratelimited drm debug print
   - DPCD PSR early transport macro
   - DP tunneling and bandwidth allocation helpers
   - remove built-in edids
   - dp: Avoid AUX transfers on powered-down displays
   - dp: Add VSC SDP helpers

  cross drivers:
   - use new drm print helpers
   - switch to ->read_edid callback
   - gem: add stats for shared buffers plus updates to amdgpu, i915, xe

  syncobj:
   - fixes to waiting and sleeping

  ttm:
   - add tests
   - fix errno codes
   - simply busy-placement handling
   - fix page decryption

  media:
   - tc358743: fix v4l device registration

  video:
   - move all kernel parameters for video behind CONFIG_VIDEO

  sound:
   - remove <drm/drm_edid.h> include from header

  ci:
   - add tests for msm
   - fix apq8016 runner

  efifb:
   - use copy of global screen_info state

  vesafb:
   - use copy of global screen_info state

  simplefb:
   - fix logging

  bridge:
   - ite-6505: fix DP link-training bug
   - samsung-dsim: fix error checking in probe
   - samsung-dsim: add bsh-smm-s2/pro boards
   - tc358767: fix regmap usage
   - imx: add i.MX8MP HDMI PVI plus DT bindings
   - imx: add i.MX8MP HDMI TX plus DT bindings
   - sii902x: fix probing and unregistration
   - tc358767: limit pixel PLL input range
   - switch to new drm_bridge_read_edid() interface

  panel:
   - ltk050h3146w: error-handling fixes
   - panel-edp: support delay between power-on and enable; use put_sync
     in unprepare; support Mediatek MT8173 Chromebooks, BOE NV116WHM-N49
     V8.0, BOE NV122WUM-N41, CSO MNC207QS1-1 plus DT bindings
   - panel-lvds: support EDT ETML0700Z9NDHA plus DT bindings
   - panel-novatek: FRIDA FRD400B25025-A-CTK plus DT bindings
   - add BOE TH101MB31IG002-28A plus DT bindings
   - add EDT ETML1010G3DRA plus DT bindings
   - add Novatek NT36672E LCD DSI plus DT bindings
   - nt36523: support 120Hz timings, fix includes
   - simple: fix display timings on RK32FN48H
   - visionox-vtdr6130: fix initialization
   - add Powkiddy RGB10MAX3 plus DT bindings
   - st7703: support panel rotation plus DT bindings
   - add Himax HX83112A plus DT bindings
   - ltk500hd1829: add support for ltk101b4029w and admatec 9904370
   - simple: add BOE BP082WX1-100 8.2" panel plus DT bindungs

  panel-orientation-quirks:
   - GPD Win Mini

  amdgpu:
   - Validate DMABuf imports in compute VMs
   - Add RAS ACA framework
   - PSP 13 fixes
   - Misc code cleanups
   - Replay fixes
   - Atom interpretor PS, WS bounds checking
   - DML2 fixes
   - Audio fixes
   - DCN 3.5 Z state fixes
   - Remove deprecated ida_simple usage
   - UBSAN fixes
   - RAS fixes
   - Enable seq64 infrastructure
   - DC color block enablement
   - Documentation updates
   - DC documentation updates
   - DMCUB updates
   - ATHUB 4.1 support
   - LSDMA 7.0 support
   - JPEG DPG support
   - IH 7.0 support
   - HDP 7.0 support
   - VCN 5.0 support
   - SMU 13.0.6 updates
   - NBIO 7.11 updates
   - SDMA 6.1 updates
   - MMHUB 3.3 updates
   - DCN 3.5.1 support
   - NBIF 6.3.1 support
   - VPE 6.1.1 support

  amdkfd:
   - Validate DMABuf imports in compute VMs
   - SVM fixes
   - Trap handler updates and enhancements
   - Fix cache size reporting
   - Relocate the trap handler

  radeon:
   - Atom interpretor PS, WS bounds checking
   - Misc code cleanups

  xe:
   - new query for GuC submission version
   - Remove unused persistent exec_queues
   - Add vram frequency sysfs attributes
   - Add the flag XE_VM_BIND_FLAG_DUMPABLE
   - Drop pre-production workarounds
   - Drop kunit tests for unsupported platforms
   - Start pumbling SR-IOV support with memory based interrupts for VF
   - Allow to map BO in GGTT with PAT index corresponding to XE_CACHE_UC
     to work with memory based interrupts
   - Add GuC Doorbells Manager as prep work SR-IOV
   - Implement additional workarounds for xe2 and MTL
   - Program a few registers according to perfomance guide spec for Xe2
   - Fix remaining 32b build issues and enable it back
   - Fix build with CONFIG_DEBUG_FS=n
   - Fix warnings from GuC ABI headers
   - Introduce Relay Communication for SR-IOV for VF <-> GuC <-> PF
   - Release mmap mappings on rpm suspend
   - Disable mid-thread preemption when not properly supported by
     hardware
   - Fix xe_exec by reserving extra fence slot for CPU bind
   - Fix xe_exec with full long running exec queue
   - Canonicalize addresses where needed for Xe2 and add to devcoredum
   - Toggle USM support for Xe2
   - Only allow 1 ufence per exec / bind IOCTL
   - Add GuC firmware loading for Lunar Lake
   - Add XE_VMA_PTE_64K VMA flag

  i915:
   - Add more ADL-N PCI IDs
   - Enable fastboot also on older platforms
   - Early transport for panel replay and PSR
   - New ARL PCI IDs
   - DP TPS4 PHY test pattern support
   - Unify and improve VSC SDP for PSR and non-PSR cases
   - Refactor memory regions and improve debug logging
   - Rework global state serialization
   - Remove unused CDCLK divider fields
   - Unify HDCP connector logging format
   - Use display instead of graphics version in display code
   - Move VBT and opregion debugfs next to the implementation
   - Abstract opregion interface, use opaque type
   - MTL fixes
   - HPD handling fixes
   - Add GuC submission interface version query
   - Atomically invalidate userptr on mmu-notifier
   - Update handling of MMIO triggered reports
   - Don't make assumptions about intel_wakeref_t type
   - Extend driver code of Xe_LPG to Xe_LPG+
   - Add flex arrays to struct i915_syncmap
   - Allow for very slow HuC loading
   - DP tunneling and bandwidth allocation support

  msm:
   - Correct bindings for MSM8976 and SM8650 platforms
   - Start migration of MDP5 platforms to DPU driver
   - X1E80100 MDSS support
   - DPU:
      - Improve DSC allocation, fixing several important corner cases
      - Add support for SDM630/SDM660 platforms
      - Simplify dpu_encoder_phys_ops
      - Apply fixes targeting DSC support with a single DSC encoder
      - Apply fixes for HCTL_EN timing configuration
      - X1E80100 support
      - Add support for YUV420 over DP
   - GPU:
      - fix sc7180 UBWC config
      - fix a7xx LLC config
      - new gpu support: a305B, a750, a702
      - machine support: SM7150 (different power levels than other a618)
      - a7xx devcoredump support

  habanalabs:
   - configure IRQ affinity according to NUMA node
   - move HBM MMU page tables inside the HBM
   - improve device reset
   - check extended PCIe errors

  ivpu:
   - updates to firmware API
   - refactor BO allocation

  imx:
   - use devm_ functions during init

  hisilicon:
   - fix EDID includes

  mgag200:
   - improve ioremap usage
   - convert to struct drm_edid
   - Work around PCI write bursts

  nouveau:
   - disp: use kmemdup()
   - fix EDID includes
   - documentation fixes

  qaic:
   - fixes to BO handling
   - make use of DRM managed release
   - fix order of remove operations

  rockchip:
   - analogix_dp: get encoder port from DT
   - inno_hdmi: support HDMI for RK3128
   - lvds: error-handling fixes

  ssd130x:
   - support SSD133x plus DT bindings

  tegra:
   - fix error handling

  tilcdc:
   - make use of DRM managed release

  v3d:
   - show memory stats in debugfs
   - Support display MMU page size

  vc4:
   - fix error handling in plane prepare_fb
   - fix framebuffer test in plane helpers

  virtio:
   - add venus capset defines

  vkms:
   - fix OOB access when programming the LUT
   - Kconfig improvements

  vmwgfx:
   - unmap surface before changing plane state
   - fix memory leak in error handling
   - documentation fixes
   - list command SVGA_3D_CMD_DEFINE_GB_SURFACE_V4 as invalid
   - fix null-pointer deref in execbuf
   - refactor display-mode probing
   - fix fencing for creating cursor MOBs
   - fix cursor-memory lifetime

  xlnx:
   - fix live video input for ZynqMP DPSUB

  lima:
   - fix memory leak

  loongson:
   - fail if no VRAM present

  meson:
   - switch to new drm_bridge_read_edid() interface

  renesas:
   - add RZ/G2L DU support plus DT bindings

  mxsfb:
   - Use managed mode config

  sun4i:
   - HDMI: updates to atomic mode setting

  mediatek:
   - Add display driver for MT8188 VDOSYS1
   - DSI driver cleanups
   - Filter modes according to hardware capability
   - Fix a null pointer crash in mtk_drm_crtc_finish_page_flip

  etnaviv:
   - enhancements for NPU and MRT support"

* tag 'drm-next-2024-03-13' of https://gitlab.freedesktop.org/drm/kernel: (1420 commits)
  drm/amd/display: Removed redundant @ symbol to fix kernel-doc warnings in -next repo
  drm/amd/pm: wait for completion of the EnableGfxImu message
  drm/amdgpu/soc21: add mode2 asic reset for SMU IP v14.0.1
  drm/amdgpu: add smu 14.0.1 support
  drm/amdgpu: add VPE 6.1.1 discovery support
  drm/amdgpu/vpe: add VPE 6.1.1 support
  drm/amdgpu/vpe: don't emit cond exec command under collaborate mode
  drm/amdgpu/vpe: add collaborate mode support for VPE
  drm/amdgpu/vpe: add PRED_EXE and COLLAB_SYNC OPCODE
  drm/amdgpu/vpe: add multi instance VPE support
  drm/amdgpu/discovery: add nbif v6_3_1 ip block
  drm/amdgpu: Add nbif v6_3_1 ip block support
  drm/amdgpu: Add pcie v6_1_0 ip headers (v5)
  drm/amdgpu: Add nbif v6_3_1 ip headers (v5)
  arch/powerpc: Remove <linux/fb.h> from backlight code
  macintosh/via-pmu-backlight: Include <linux/backlight.h>
  fbdev/chipsfb: Include <linux/backlight.h>
  drm/etnaviv: Restore some id values
  drm/amdkfd: make kfd_class constant
  drm/amdgpu: add ring timeout information in devcoredump
  ...
  • [D] Documentation/admin-guide/kernel-parameters.txt
Merge tag 'pm-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm 2024-03-13T18:40:06Z Linus Torvalds torvalds@linux-foundation.org Linus Torvalds torvalds@linux-foundation.org 2024-03-13T18:40:06Z http://git.samba.org/samba.git/?p=sfrench/cifs-2.6.git;a=commitdiff;h=07abb19a9b201c11e4367e8a428be7235b6dbd0d
Merge tag 'pm-6.9-rc1' of git://git./linux/kernel/git/rafael/linux-pm

Pull power management updates from Rafael Wysocki:
 "From the functional perspective, the most significant change here is
  the addition of support for Energy Models that can be updated
  dynamically at run time.

  There is also the addition of LZ4 compression support for hibernation,
  the new preferred core support in amd-pstate, new platforms support in
  the Intel RAPL driver, new model-specific EPP handling in intel_pstate
  and more.

  Apart from that, the cpufreq default transition delay is reduced from
  10 ms to 2 ms (along with some related adjustments), the system
  suspend statistics code undergoes a significant rework and there is a
  usual bunch of fixes and code cleanups all over.

  Specifics:

   - Allow the Energy Model to be updated dynamically (Lukasz Luba)

   - Add support for LZ4 compression algorithm to the hibernation image
     creation and loading code (Nikhil V)

   - Fix and clean up system suspend statistics collection (Rafael
     Wysocki)

   - Simplify device suspend and resume handling in the power management
     core code (Rafael Wysocki)

   - Fix PCI hibernation support description (Yiwei Lin)

   - Make hibernation take set_memory_ro() return values into account as
     appropriate (Christophe Leroy)

   - Set mem_sleep_current during kernel command line setup to avoid an
     ordering issue with handling it (Maulik Shah)

   - Fix wake IRQs handling when pm_runtime_force_suspend() is used as a
     driver's system suspend callback (Qingliang Li)

   - Simplify pm_runtime_get_if_active() usage and add a replacement for
     pm_runtime_put_autosuspend() (Sakari Ailus)

   - Add a tracepoint for runtime_status changes tracking (Vilas Bhat)

   - Fix section title markdown in the runtime PM documentation (Yiwei
     Lin)

   - Enable preferred core support in the amd-pstate cpufreq driver
     (Meng Li)

   - Fix min_perf assignment in amd_pstate_adjust_perf() and make the
     min/max limit perf values in amd-pstate always stay within the
     (highest perf, lowest perf) range (Tor Vic, Meng Li)

   - Allow intel_pstate to assign model-specific values to strings used
     in the EPP sysfs interface and make it do so on Meteor Lake
     (Srinivas Pandruvada)

   - Drop long-unused cpudata::prev_cummulative_iowait from the
     intel_pstate cpufreq driver (Jiri Slaby)

   - Prevent scaling_cur_freq from exceeding scaling_max_freq when the
     latter is an inefficient frequency (Shivnandan Kumar)

   - Change default transition delay in cpufreq to 2ms (Qais Yousef)

   - Remove references to 10ms minimum sampling rate from comments in
     the cpufreq code (Pierre Gondois)

   - Honour transition_latency over transition_delay_us in cpufreq (Qais
     Yousef)

   - Stop unregistering cpufreq cooling on CPU hot-remove (Viresh Kumar)

   - General enhancements / cleanups to ARM cpufreq drivers (tianyu2,
     NĂ­colas F. R. A. Prado, Erick Archer, Arnd Bergmann, Anastasia
     Belova)

   - Update cpufreq-dt-platdev to block/approve devices (Richard Acayan)

   - Make the SCMI cpufreq driver get a transition delay value from
     firmware (Pierre Gondois)

   - Prevent the haltpoll cpuidle governor from shrinking guest
     poll_limit_ns below grow_start (Parshuram Sangle)

   - Avoid potential overflow in integer multiplication when computing
     cpuidle state parameters (C Cheng)

   - Adjust MWAIT hint target C-state computation in the ACPI cpuidle
     driver and in intel_idle to return a correct value for C0 (He
     Rongguang)

   - Address multiple issues in the TPMI RAPL driver and add support for
     new platforms (Lunar Lake-M, Arrow Lake) to Intel RAPL (Zhang Rui)

   - Fix freq_qos_add_request() return value check in dtpm_cpu (Daniel
     Lezcano)

   - Fix kernel-doc for dtpm_create_hierarchy() (Yang Li)

   - Fix file leak in get_pkg_num() in x86_energy_perf_policy (Samasth
     Norway Ananda)

   - Fix cpupower-frequency-info.1 man page typo (Jan Kratochvil)

   - Fix a couple of warnings in the OPP core code related to W=1 builds
     (Viresh Kumar)

   - Move dev_pm_opp_{init|free}_cpufreq_table() to pm_opp.h (Viresh
     Kumar)

   - Extend dev_pm_opp_data with turbo support (Sibi Sankar)

   - dt-bindings: drop maxItems from inner items (David Heidelberg)"

* tag 'pm-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (95 commits)
  dt-bindings: opp: drop maxItems from inner items
  OPP: debugfs: Fix warning around icc_get_name()
  OPP: debugfs: Fix warning with W=1 builds
  cpufreq: Move dev_pm_opp_{init|free}_cpufreq_table() to pm_opp.h
  OPP: Extend dev_pm_opp_data with turbo support
  Fix cpupower-frequency-info.1 man page typo
  cpufreq: scmi: Set transition_delay_us
  firmware: arm_scmi: Populate fast channel rate_limit
  firmware: arm_scmi: Populate perf commands rate_limit
  cpuidle: ACPI/intel: fix MWAIT hint target C-state computation
  PM: sleep: wakeirq: fix wake irq warning in system suspend
  powercap: dtpm: Fix kernel-doc for dtpm_create_hierarchy() function
  cpufreq: Don't unregister cpufreq cooling on CPU hotplug
  PM: suspend: Set mem_sleep_current during kernel command line setup
  cpufreq: Honour transition_latency over transition_delay_us
  cpufreq: Limit resolving a frequency to policy min/max
  Documentation: PM: Fix runtime_pm.rst markdown syntax
  cpufreq: amd-pstate: adjust min/max limit perf
  cpufreq: Remove references to 10ms min sampling rate
  cpufreq: intel_pstate: Update default EPPs for Meteor Lake
  ...
  • [D] Documentation/admin-guide/kernel-parameters.txt
Merge tag 'slab-for-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka... 2024-03-13T03:14:54Z Linus Torvalds torvalds@linux-foundation.org Linus Torvalds torvalds@linux-foundation.org 2024-03-13T03:14:54Z http://git.samba.org/samba.git/?p=sfrench/cifs-2.6.git;a=commitdiff;h=0ea680eda6c9f59a9512f8b0dd4abf229bb9f6cf
Merge tag 'slab-for-6.9' of git://git./linux/kernel/git/vbabka/slab

Pull slab updates from Vlastimil Babka:

 - Freelist loading optimization (Chengming Zhou)

   When the per-cpu slab is depleted and a new one loaded from the cpu
   partial list, optimize the loading to avoid an irq enable/disable
   cycle. This results in a 3.5% performance improvement on the "perf
   bench sched messaging" test.

 - Kernel boot parameters cleanup after SLAB removal (Xiongwei Song)

   Due to two different main slab implementations we've had boot
   parameters prefixed either slab_ and slub_ with some later becoming
   an alias as both implementations gained the same functionality (i.e.
   slab_nomerge vs slub_nomerge). In order to eventually get rid of the
   implementation-specific names, the canonical and documented
   parameters are now all prefixed slab_ and the slub_ variants become
   deprecated but still working aliases.

 - SLAB_ kmem_cache creation flags cleanup (Vlastimil Babka)

   The flags had hardcoded #define values which became tedious and
   error-prone when adding new ones. Assign the values via an enum that
   takes care of providing unique bit numbers. Also deprecate
   SLAB_MEM_SPREAD which was only used by SLAB, so it's a no-op since
   SLAB removal. Assign it an explicit zero value. The removals of the
   flag usage are handled independently in the respective subsystems,
   with a final removal of any leftover usage planned for the next
   release.

 - Misc cleanups and fixes (Chengming Zhou, Xiaolei Wang, Zheng Yejian)

   Includes removal of unused code or function parameters and a fix of a
   memleak.

* tag 'slab-for-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab:
  slab: remove PARTIAL_NODE slab_state
  mm, slab: remove memcg_from_slab_obj()
  mm, slab: remove the corner case of inc_slabs_node()
  mm/slab: Fix a kmemleak in kmem_cache_destroy()
  mm, slab, kasan: replace kasan_never_merge() with SLAB_NO_MERGE
  mm, slab: use an enum to define SLAB_ cache creation flags
  mm, slab: deprecate SLAB_MEM_SPREAD flag
  mm, slab: fix the comment of cpu partial list
  mm, slab: remove unused object_size parameter in kmem_cache_flags()
  mm/slub: remove parameter 'flags' in create_kmalloc_caches()
  mm/slub: remove unused parameter in next_freelist_entry()
  mm/slub: remove full list manipulation for non-debug slab
  mm/slub: directly load freelist from cpu partial slab in the likely case
  mm/slub: make the description of slab_min_objects helpful in doc
  mm/slub: replace slub_$params with slab_$params in slub.rst
  mm/slub: unify all sl[au]b parameters with "slab_$param"
  Documentation: kernel-parameters: remove noaliencache
  • [D] Documentation/admin-guide/kernel-parameters.txt
Merge tag 'docs-6.9' of git://git.lwn.net/linux 2024-03-12T22:18:34Z Linus Torvalds torvalds@linux-foundation.org Linus Torvalds torvalds@linux-foundation.org 2024-03-12T22:18:34Z http://git.samba.org/samba.git/?p=sfrench/cifs-2.6.git;a=commitdiff;h=1f440397665f4241346e4cc6d93f8b73880815d1
Merge tag 'docs-6.9' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "A moderatly busy cycle for development this time around.

   - Some cleanup of the main index page for easier navigation

   - Rework some of the other top-level pages for better readability
     and, with luck, fewer merge conflicts in the future.

   - Submit-checklist improvements, hopefully the first of many.

   - New Italian translations

   - A fair number of kernel-doc fixes and improvements. We have also
     dropped the recommendation to use an old version of Sphinx.

   - A new document from Thorsten on bisection

  ... and lots of fixes and updates"

* tag 'docs-6.9' of git://git.lwn.net/linux: (54 commits)
  docs: verify/bisect: fixes, finetuning, and support for Arch
  docs: Makefile: Add dependency to $(YNL_INDEX) for targets other than htmldocs
  docs: Move ja_JP/howto.rst to ja_JP/process/howto.rst
  docs: submit-checklist: use subheadings
  docs: submit-checklist: structure by category
  docs: new text on bisecting which also covers bug validation
  docs: drop the version constraints for sphinx and dependencies
  docs: kerneldoc-preamble.sty: Remove code for Sphinx <2.4
  docs: Restore "smart quotes" for quotes
  docs/zh_CN: accurate translation of "function"
  docs: Include simplified link titles in main index
  docs: Correct formatting of title in admin-guide/index.rst
  docs: kernel_feat.py: fix build error for missing files
  MAINTAINERS: Set the field name for subsystem profile section
  kasan: Add documentation for CONFIG_KASAN_EXTRA_INFO
  Fixed case issue with 'fault-injection' in documentation
  kernel-doc: handle #if in enums as well
  Documentation: update mailing list addresses
  doc: kerneldoc.py: fix indentation
  scripts/kernel-doc: simplify signature printing
  ...
  • [D] Documentation/admin-guide/kernel-parameters.txt
Merge tag 'rfds-for-linus-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel... 2024-03-12T16:31:39Z Linus Torvalds torvalds@linux-foundation.org Linus Torvalds torvalds@linux-foundation.org 2024-03-12T16:31:39Z http://git.samba.org/samba.git/?p=sfrench/cifs-2.6.git;a=commitdiff;h=0e33cf955f07e3991e45109cb3e29fbc9ca51d06
Merge tag 'rfds-for-linus-2024-03-11' of git://git./linux/kernel/git/tip/tip

Pull x86 RFDS mitigation from Dave Hansen:
 "RFDS is a CPU vulnerability that may allow a malicious userspace to
  infer stale register values from kernel space. Kernel registers can
  have all kinds of secrets in them so the mitigation is basically to
  wait until the kernel is about to return to userspace and has user
  values in the registers. At that point there is little chance of
  kernel secrets ending up in the registers and the microarchitectural
  state can be cleared.

  This leverages some recent robustness fixes for the existing MDS
  vulnerability. Both MDS and RFDS use the VERW instruction for
  mitigation"

* tag 'rfds-for-linus-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  KVM/x86: Export RFDS_NO and RFDS_CLEAR to guests
  x86/rfds: Mitigate Register File Data Sampling (RFDS)
  Documentation/hw-vuln: Add documentation for RFDS
  x86/mmio: Disable KVM mitigation when X86_FEATURE_CLEAR_CPU_BUF is set
  • [D] Documentation/admin-guide/kernel-parameters.txt
Merge tag 'x86-core-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git... 2024-03-12T02:53:15Z Linus Torvalds torvalds@linux-foundation.org Linus Torvalds torvalds@linux-foundation.org 2024-03-12T02:53:15Z http://git.samba.org/samba.git/?p=sfrench/cifs-2.6.git;a=commitdiff;h=685d98211273f60e38a6d361b62d7016c545297e
Merge tag 'x86-core-2024-03-11' of git://git./linux/kernel/git/tip/tip

Pull core x86 updates from Ingo Molnar:

 - The biggest change is the rework of the percpu code, to support the
   'Named Address Spaces' GCC feature, by Uros Bizjak:

      - This allows C code to access GS and FS segment relative memory
        via variables declared with such attributes, which allows the
        compiler to better optimize those accesses than the previous
        inline assembly code.

      - The series also includes a number of micro-optimizations for
        various percpu access methods, plus a number of cleanups of %gs
        accesses in assembly code.

      - These changes have been exposed to linux-next testing for the
        last ~5 months, with no known regressions in this area.

 - Fix/clean up __switch_to()'s broken but accidentally working handling
   of FPU switching - which also generates better code

 - Propagate more RIP-relative addressing in assembly code, to generate
   slightly better code

 - Rework the CPU mitigations Kconfig space to be less idiosyncratic, to
   make it easier for distros to follow & maintain these options

 - Rework the x86 idle code to cure RCU violations and to clean up the
   logic

 - Clean up the vDSO Makefile logic

 - Misc cleanups and fixes

* tag 'x86-core-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits)
  x86/idle: Select idle routine only once
  x86/idle: Let prefer_mwait_c1_over_halt() return bool
  x86/idle: Cleanup idle_setup()
  x86/idle: Clean up idle selection
  x86/idle: Sanitize X86_BUG_AMD_E400 handling
  sched/idle: Conditionally handle tick broadcast in default_idle_call()
  x86: Increase brk randomness entropy for 64-bit systems
  x86/vdso: Move vDSO to mmap region
  x86/vdso/kbuild: Group non-standard build attributes and primary object file rules together
  x86/vdso: Fix rethunk patching for vdso-image-{32,64}.o
  x86/retpoline: Ensure default return thunk isn't used at runtime
  x86/vdso: Use CONFIG_COMPAT_32 to specify vdso32
  x86/vdso: Use $(addprefix ) instead of $(foreach )
  x86/vdso: Simplify obj-y addition
  x86/vdso: Consolidate targets and clean-files
  x86/bugs: Rename CONFIG_RETHUNK              => CONFIG_MITIGATION_RETHUNK
  x86/bugs: Rename CONFIG_CPU_SRSO             => CONFIG_MITIGATION_SRSO
  x86/bugs: Rename CONFIG_CPU_IBRS_ENTRY       => CONFIG_MITIGATION_IBRS_ENTRY
  x86/bugs: Rename CONFIG_CPU_UNRET_ENTRY      => CONFIG_MITIGATION_UNRET_ENTRY
  x86/bugs: Rename CONFIG_SLS                  => CONFIG_MITIGATION_SLS
  ...
  • [D] Documentation/admin-guide/kernel-parameters.txt
Merge tag 'x86_misc_for_v6.9_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git... 2024-03-12T01:02:44Z Linus Torvalds torvalds@linux-foundation.org Linus Torvalds torvalds@linux-foundation.org 2024-03-12T01:02:44Z http://git.samba.org/samba.git/?p=sfrench/cifs-2.6.git;a=commitdiff;h=1f75619a721d5149d9a947f2177d3cffc473fbb7
Merge tag 'x86_misc_for_v6.9_rc1' of git://git./linux/kernel/git/tip/tip

Pull misc x86 fixes from Borislav Petkov:

 - Fix a wrong check in the function reporting whether a CPU executes
   (or not) a NMI handler

 - Ratelimit unknown NMIs messages in order to not potentially slow down
   the machine

 - Other fixlets

* tag 'x86_misc_for_v6.9_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/nmi: Fix the inverse "in NMI handler" check
  Documentation/maintainer-tip: Add C++ tail comments exception
  Documentation/maintainer-tip: Add Closes tag
  x86/nmi: Rate limit unknown NMI messages
  Documentation/kernel-parameters: Add spec_rstack_overflow to mitigations=off
  • [D] Documentation/admin-guide/kernel-parameters.txt
Merge tag 'x86_sev_for_v6.9_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git... 2024-03-12T00:44:11Z Linus Torvalds torvalds@linux-foundation.org Linus Torvalds torvalds@linux-foundation.org 2024-03-12T00:44:11Z http://git.samba.org/samba.git/?p=sfrench/cifs-2.6.git;a=commitdiff;h=38b334fc767e44816be087b3ec5d84b1438b735f
Merge tag 'x86_sev_for_v6.9_rc1' of git://git./linux/kernel/git/tip/tip

Pull x86 SEV updates from Borislav Petkov:

 - Add the x86 part of the SEV-SNP host support.

   This will allow the kernel to be used as a KVM hypervisor capable of
   running SNP (Secure Nested Paging) guests. Roughly speaking, SEV-SNP
   is the ultimate goal of the AMD confidential computing side,
   providing the most comprehensive confidential computing environment
   up to date.

   This is the x86 part and there is a KVM part which did not get ready
   in time for the merge window so latter will be forthcoming in the
   next cycle.

 - Rework the early code's position-dependent SEV variable references in
   order to allow building the kernel with clang and -fPIE/-fPIC and
   -mcmodel=kernel

 - The usual set of fixes, cleanups and improvements all over the place

* tag 'x86_sev_for_v6.9_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
  x86/sev: Disable KMSAN for memory encryption TUs
  x86/sev: Dump SEV_STATUS
  crypto: ccp - Have it depend on AMD_IOMMU
  iommu/amd: Fix failure return from snp_lookup_rmpentry()
  x86/sev: Fix position dependent variable references in startup code
  crypto: ccp: Make snp_range_list static
  x86/Kconfig: Remove CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
  Documentation: virt: Fix up pre-formatted text block for SEV ioctls
  crypto: ccp: Add the SNP_SET_CONFIG command
  crypto: ccp: Add the SNP_COMMIT command
  crypto: ccp: Add the SNP_PLATFORM_STATUS command
  x86/cpufeatures: Enable/unmask SEV-SNP CPU feature
  KVM: SEV: Make AVIC backing, VMSA and VMCB memory allocation SNP safe
  crypto: ccp: Add panic notifier for SEV/SNP firmware shutdown on kdump
  iommu/amd: Clean up RMP entries for IOMMU pages during SNP shutdown
  crypto: ccp: Handle legacy SEV commands when SNP is enabled
  crypto: ccp: Handle non-volatile INIT_EX data when SNP is enabled
  crypto: ccp: Handle the legacy TMR allocation when SNP is enabled
  x86/sev: Introduce an SNP leaked pages list
  crypto: ccp: Provide an API to issue SEV and SNP commands
  ...
  • [D] Documentation/admin-guide/kernel-parameters.txt
Merge tag 'x86-fred-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git... 2024-03-11T23:00:17Z Linus Torvalds torvalds@linux-foundation.org Linus Torvalds torvalds@linux-foundation.org 2024-03-11T23:00:17Z http://git.samba.org/samba.git/?p=sfrench/cifs-2.6.git;a=commitdiff;h=720c857907530e6cdc86c9bc1102ea6b372fbfb6
Merge tag 'x86-fred-2024-03-10' of git://git./linux/kernel/git/tip/tip

Pull x86 FRED support from Thomas Gleixner:
 "Support for x86 Fast Return and Event Delivery (FRED).

  FRED is a replacement for IDT event delivery on x86 and addresses most
  of the technical nightmares which IDT exposes:

   1) Exception cause registers like CR2 need to be manually preserved
      in nested exception scenarios.

   2) Hardware interrupt stack switching is suboptimal for nested
      exceptions as the interrupt stack mechanism rewinds the stack on
      each entry which requires a massive effort in the low level entry
      of #NMI code to handle this.

   3) No hardware distinction between entry from kernel or from user
      which makes establishing kernel context more complex than it needs
      to be especially for unconditionally nestable exceptions like NMI.

   4) NMI nesting caused by IRET unconditionally reenabling NMIs, which
      is a problem when the perf NMI takes a fault when collecting a
      stack trace.

   5) Partial restore of ESP when returning to a 16-bit segment

   6) Limitation of the vector space which can cause vector exhaustion
      on large systems.

   7) Inability to differentiate NMI sources

  FRED addresses these shortcomings by:

   1) An extended exception stack frame which the CPU uses to save
      exception cause registers. This ensures that the meta information
      for each exception is preserved on stack and avoids the extra
      complexity of preserving it in software.

   2) Hardware interrupt stack switching is non-rewinding if a nested
      exception uses the currently interrupt stack.

   3) The entry points for kernel and user context are separate and GS
      BASE handling which is required to establish kernel context for
      per CPU variable access is done in hardware.

   4) NMIs are now nesting protected. They are only reenabled on the
      return from NMI.

   5) FRED guarantees full restore of ESP

   6) FRED does not put a limitation on the vector space by design
      because it uses a central entry points for kernel and user space
      and the CPUstores the entry type (exception, trap, interrupt,
      syscall) on the entry stack along with the vector number. The
      entry code has to demultiplex this information, but this removes
      the vector space restriction.

      The first hardware implementations will still have the current
      restricted vector space because lifting this limitation requires
      further changes to the local APIC.

   7) FRED stores the vector number and meta information on stack which
      allows having more than one NMI vector in future hardware when the
      required local APIC changes are in place.

  The series implements the initial FRED support by:

   - Reworking the existing entry and IDT handling infrastructure to
     accomodate for the alternative entry mechanism.

   - Expanding the stack frame to accomodate for the extra 16 bytes FRED
     requires to store context and meta information

   - Providing FRED specific C entry points for events which have
     information pushed to the extended stack frame, e.g. #PF and #DB.

   - Providing FRED specific C entry points for #NMI and #MCE

   - Implementing the FRED specific ASM entry points and the C code to
     demultiplex the events

   - Providing detection and initialization mechanisms and the necessary
     tweaks in context switching, GS BASE handling etc.

  The FRED integration aims for maximum code reuse vs the existing IDT
  implementation to the extent possible and the deviation in hot paths
  like context switching are handled with alternatives to minimalize the
  impact. The low level entry and exit paths are seperate due to the
  extended stack frame and the hardware based GS BASE swichting and
  therefore have no impact on IDT based systems.

  It has been extensively tested on existing systems and on the FRED
  simulation and as of now there are no outstanding problems"

* tag 'x86-fred-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits)
  x86/fred: Fix init_task thread stack pointer initialization
  MAINTAINERS: Add a maintainer entry for FRED
  x86/fred: Fix a build warning with allmodconfig due to 'inline' failing to inline properly
  x86/fred: Invoke FRED initialization code to enable FRED
  x86/fred: Add FRED initialization functions
  x86/syscall: Split IDT syscall setup code into idt_syscall_init()
  KVM: VMX: Call fred_entry_from_kvm() for IRQ/NMI handling
  x86/entry: Add fred_entry_from_kvm() for VMX to handle IRQ/NMI
  x86/entry/calling: Allow PUSH_AND_CLEAR_REGS being used beyond actual entry code
  x86/fred: Fixup fault on ERETU by jumping to fred_entrypoint_user
  x86/fred: Let ret_from_fork_asm() jmp to asm_fred_exit_user when FRED is enabled
  x86/traps: Add sysvec_install() to install a system interrupt handler
  x86/fred: FRED entry/exit and dispatch code
  x86/fred: Add a machine check entry stub for FRED
  x86/fred: Add a NMI entry stub for FRED
  x86/fred: Add a debug fault entry stub for FRED
  x86/idtentry: Incorporate definitions/declarations of the FRED entries
  x86/fred: Make exc_page_fault() work for FRED
  x86/fred: Allow single-step trap and NMI when starting a new task
  x86/fred: No ESPFIX needed when FRED is enabled
  ...
  • [D] Documentation/admin-guide/kernel-parameters.txt
Merge tag 'x86-apic-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git... 2024-03-11T22:45:55Z Linus Torvalds torvalds@linux-foundation.org Linus Torvalds torvalds@linux-foundation.org 2024-03-11T22:45:55Z http://git.samba.org/samba.git/?p=sfrench/cifs-2.6.git;a=commitdiff;h=ca7e917769121195bae45d4886f6e24efd6f99ae
Merge tag 'x86-apic-2024-03-10' of git://git./linux/kernel/git/tip/tip

Pull x86 APIC updates from Thomas Gleixner:
 "Rework of APIC enumeration and topology evaluation.

  The current implementation has a couple of shortcomings:

   - It fails to handle hybrid systems correctly.

   - The APIC registration code which handles CPU number assignents is
     in the middle of the APIC code and detached from the topology
     evaluation.

   - The various mechanisms which enumerate APICs, ACPI, MPPARSE and
     guest specific ones, tweak global variables as they see fit or in
     case of XENPV just hack around the generic mechanisms completely.

   - The CPUID topology evaluation code is sprinkled all over the vendor
     code and reevaluates global variables on every hotplug operation.

   - There is no way to analyze topology on the boot CPU before bringing
     up the APs. This causes problems for infrastructure like PERF which
     needs to size certain aspects upfront or could be simplified if
     that would be possible.

   - The APIC admission and CPU number association logic is
     incomprehensible and overly complex and needs to be kept around
     after boot instead of completing this right after the APIC
     enumeration.

  This update addresses these shortcomings with the following changes:

   - Rework the CPUID evaluation code so it is common for all vendors
     and provides information about the APIC ID segments in a uniform
     way independent of the number of segments (Thread, Core, Module,
     ..., Die, Package) so that this information can be computed instead
     of rewriting global variables of dubious value over and over.

   - A few cleanups and simplifcations of the APIC, IO/APIC and related
     interfaces to prepare for the topology evaluation changes.

   - Seperation of the parser stages so the early evaluation which tries
     to find the APIC address can be seperately overridden from the late
     evaluation which enumerates and registers the local APIC as further
     preparation for sanitizing the topology evaluation.

   - A new registration and admission logic which

       - encapsulates the inner workings so that parsers and guest logic
         cannot longer fiddle in it

       - uses the APIC ID segments to build topology bitmaps at
         registration time

       - provides a sane admission logic

       - allows to detect the crash kernel case, where CPU0 does not run
         on the real BSP, automatically. This is required to prevent
         sending INIT/SIPI sequences to the real BSP which would reset
         the whole machine. This was so far handled by a tedious command
         line parameter, which does not even work in nested crash
         scenarios.

       - Associates CPU number after the enumeration completed and
         prevents the late registration of APICs, which was somehow
         tolerated before.

   - Converting all parsers and guest enumeration mechanisms over to the
     new interfaces.

     This allows to get rid of all global variable tweaking from the
     parsers and enumeration mechanisms and sanitizes the XEN[PV]
     handling so it can use CPUID evaluation for the first time.

   - Mopping up existing sins by taking the information from the APIC ID
     segment bitmaps.

     This evaluates hybrid systems correctly on the boot CPU and allows
     for cleanups and fixes in the related drivers, e.g. PERF.

  The series has been extensively tested and the minimal late fallout
  due to a broken ACPI/MADT table has been addressed by tightening the
  admission logic further"

* tag 'x86-apic-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (76 commits)
  x86/topology: Ignore non-present APIC IDs in a present package
  x86/apic: Build the x86 topology enumeration functions on UP APIC builds too
  smp: Provide 'setup_max_cpus' definition on UP too
  smp: Avoid 'setup_max_cpus' namespace collision/shadowing
  x86/bugs: Use fixed addressing for VERW operand
  x86/cpu/topology: Get rid of cpuinfo::x86_max_cores
  x86/cpu/topology: Provide __num_[cores|threads]_per_package
  x86/cpu/topology: Rename topology_max_die_per_package()
  x86/cpu/topology: Rename smp_num_siblings
  x86/cpu/topology: Retrieve cores per package from topology bitmaps
  x86/cpu/topology: Use topology logical mapping mechanism
  x86/cpu/topology: Provide logical pkg/die mapping
  x86/cpu/topology: Simplify cpu_mark_primary_thread()
  x86/cpu/topology: Mop up primary thread mask handling
  x86/cpu/topology: Use topology bitmaps for sizing
  x86/cpu/topology: Let XEN/PV use topology from CPUID/MADT
  x86/xen/smp_pv: Count number of vCPUs early
  x86/cpu/topology: Assign hotpluggable CPUIDs during init
  x86/cpu/topology: Reject unknown APIC IDs on ACPI hotplug
  x86/topology: Add a mechanism to track topology via APIC IDs
  ...
  • [D] Documentation/admin-guide/kernel-parameters.txt
Merge tag 'timers-core-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git... 2024-03-11T21:38:26Z Linus Torvalds torvalds@linux-foundation.org Linus Torvalds torvalds@linux-foundation.org 2024-03-11T21:38:26Z http://git.samba.org/samba.git/?p=sfrench/cifs-2.6.git;a=commitdiff;h=d08c407f715f651e7ea40b3a037be46dd2b11e4c
Merge tag 'timers-core-2024-03-10' of git://git./linux/kernel/git/tip/tip

Pull timer updates from Thomas Gleixner:
 "A large set of updates and features for timers and timekeeping:

   - The hierarchical timer pull model

     When timer wheel timers are armed they are placed into the timer
     wheel of a CPU which is likely to be busy at the time of expiry.
     This is done to avoid wakeups on potentially idle CPUs.

     This is wrong in several aspects:

       1) The heuristics to select the target CPU are wrong by
          definition as the chance to get the prediction right is
          close to zero.

       2) Due to #1 it is possible that timers are accumulated on
          a single target CPU

       3) The required computation in the enqueue path is just overhead
          for dubious value especially under the consideration that the
          vast majority of timer wheel timers are either canceled or
          rearmed before they expire.

     The timer pull model avoids the above by removing the target
     computation on enqueue and queueing timers always on the CPU on
     which they get armed.

     This is achieved by having separate wheels for CPU pinned timers
     and global timers which do not care about where they expire.

     As long as a CPU is busy it handles both the pinned and the global
     timers which are queued on the CPU local timer wheels.

     When a CPU goes idle it evaluates its own timer wheels:

       - If the first expiring timer is a pinned timer, then the global
         timers can be ignored as the CPU will wake up before they
         expire.

       - If the first expiring timer is a global timer, then the expiry
         time is propagated into the timer pull hierarchy and the CPU
         makes sure to wake up for the first pinned timer.

     The timer pull hierarchy organizes CPUs in groups of eight at the
     lowest level and at the next levels groups of eight groups up to
     the point where no further aggregation of groups is required, i.e.
     the number of levels is log8(NR_CPUS). The magic number of eight
     has been established by experimention, but can be adjusted if
     needed.

     In each group one busy CPU acts as the migrator. It's only one CPU
     to avoid lock contention on remote timer wheels.

     The migrator CPU checks in its own timer wheel handling whether
     there are other CPUs in the group which have gone idle and have
     global timers to expire. If there are global timers to expire, the
     migrator locks the remote CPU timer wheel and handles the expiry.

     Depending on the group level in the hierarchy this handling can
     require to walk the hierarchy downwards to the CPU level.

     Special care is taken when the last CPU goes idle. At this point
     the CPU is the systemwide migrator at the top of the hierarchy and
     it therefore cannot delegate to the hierarchy. It needs to arm its
     own timer device to expire either at the first expiring timer in
     the hierarchy or at the first CPU local timer, which ever expires
     first.

     This completely removes the overhead from the enqueue path, which
     is e.g. for networking a true hotpath and trades it for a slightly
     more complex idle path.

     This has been in development for a couple of years and the final
     series has been extensively tested by various teams from silicon
     vendors and ran through extensive CI.

     There have been slight performance improvements observed on network
     centric workloads and an Intel team confirmed that this allows them
     to power down a die completely on a mult-die socket for the first
     time in a mostly idle scenario.

     There is only one outstanding ~1.5% regression on a specific
     overloaded netperf test which is currently investigated, but the
     rest is either positive or neutral performance wise and positive on
     the power management side.

   - Fixes for the timekeeping interpolation code for cross-timestamps:

     cross-timestamps are used for PTP to get snapshots from hardware
     timers and interpolated them back to clock MONOTONIC. The changes
     address a few corner cases in the interpolation code which got the
     math and logic wrong.

   - Simplifcation of the clocksource watchdog retry logic to
     automatically adjust to handle larger systems correctly instead of
     having more incomprehensible command line parameters.

   - Treewide consolidation of the VDSO data structures.

   - The usual small improvements and cleanups all over the place"

* tag 'timers-core-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (62 commits)
  timer/migration: Fix quick check reporting late expiry
  tick/sched: Fix build failure for CONFIG_NO_HZ_COMMON=n
  vdso/datapage: Quick fix - use asm/page-def.h for ARM64
  timers: Assert no next dyntick timer look-up while CPU is offline
  tick: Assume timekeeping is correctly handed over upon last offline idle call
  tick: Shut down low-res tick from dying CPU
  tick: Split nohz and highres features from nohz_mode
  tick: Move individual bit features to debuggable mask accesses
  tick: Move got_idle_tick away from common flags
  tick: Assume the tick can't be stopped in NOHZ_MODE_INACTIVE mode
  tick: Move broadcast cancellation up to CPUHP_AP_TICK_DYING
  tick: Move tick cancellation up to CPUHP_AP_TICK_DYING
  tick: Start centralizing tick related CPU hotplug operations
  tick/sched: Don't clear ts::next_tick again in can_stop_idle_tick()
  tick/sched: Rename tick_nohz_stop_sched_tick() to tick_nohz_full_stop_tick()
  tick: Use IS_ENABLED() whenever possible
  tick/sched: Remove useless oneshot ifdeffery
  tick/nohz: Remove duplicate between lowres and highres handlers
  tick/nohz: Remove duplicate between tick_nohz_switch_to_nohz() and tick_setup_sched_timer()
  hrtimer: Select housekeeping CPU during migration
  ...
  • [D] Documentation/admin-guide/kernel-parameters.txt
x86/rfds: Mitigate Register File Data Sampling (RFDS) 2024-03-11T19:29:43Z Pawan Gupta pawan.kumar.gupta@linux.intel.com Dave Hansen dave.hansen@linux.intel.com 2024-03-11T19:29:43Z http://git.samba.org/samba.git/?p=sfrench/cifs-2.6.git;a=commitdiff;h=8076fcde016c9c0e0660543e67bff86cb48a7c9c
x86/rfds: Mitigate Register File Data Sampling (RFDS)

RFDS is a CPU vulnerability that may allow userspace to infer kernel
stale data previously used in floating point registers, vector registers
and integer registers. RFDS only affects certain Intel Atom processors.

Intel released a microcode update that uses VERW instruction to clear
the affected CPU buffers. Unlike MDS, none of the affected cores support
SMT.

Add RFDS bug infrastructure and enable the VERW based mitigation by
default, that clears the affected buffers just before exiting to
userspace. Also add sysfs reporting and cmdline parameter
"reg_file_data_sampling" to control the mitigation.

For details see:
Documentation/admin-guide/hw-vuln/reg-file-data-sampling.rst

Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
  • [D] Documentation/admin-guide/kernel-parameters.txt
Merge tag 'wq-for-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq 2024-03-11T19:50:42Z Linus Torvalds torvalds@linux-foundation.org Linus Torvalds torvalds@linux-foundation.org 2024-03-11T19:50:42Z http://git.samba.org/samba.git/?p=sfrench/cifs-2.6.git;a=commitdiff;h=ff887eb07cf69a5c0a507a1311fb34bcd38450aa
Merge tag 'wq-for-6.9' of git://git./linux/kernel/git/tj/wq

Pull workqueue updates from Tejun Heo:
 "This cycle, a lot of workqueue changes including some that are
  significant and invasive.

   - During v6.6 cycle, unbound workqueues were updated so that they are
     more topology aware and flexible, which among other things improved
     workqueue behavior on modern multi-L3 CPUs. In the process, commit
     636b927eba5b ("workqueue: Make unbound workqueues to use per-cpu
     pool_workqueues") switched unbound workqueues to use per-CPU
     frontend pool_workqueues as a part of increasing front-back mapping
     flexibility.

     An unwelcome side effect of this change was that this made max
     concurrency enforcement per-CPU blowing up the maximum number of
     allowed concurrent executions. I incorrectly assumed that this
     wouldn't cause practical problems as most unbound workqueue users
     are self-regulate max concurrency; however, there definitely are
     which don't (e.g. on IO paths) and the drastic increase in the
     allowed max concurrency led to noticeable perf regressions in some
     use cases.

     This is now addressed by separating out max concurrency enforcement
     to a separate struct - wq_node_nr_active - which makes @max_active
     consistently mean system-wide max concurrency regardless of the
     number of CPUs or (finally) NUMA nodes. This is a rather invasive
     and, in places, a bit clunky; however, the clunkiness rises from
     the the inherent requirement to handle the disagreement between the
     execution locality domain and max concurrency enforcement domain on
     some modern machines.

     See commit 5797b1c18919 ("workqueue: Implement system-wide
     nr_active enforcement for unbound workqueues") for more details.

   - BH workqueue support is added.

     They are similar to per-CPU workqueues but execute work items in
     the softirq context. This is expected to replace tasklet. However,
     currently, it's missing the ability to disable and enable work
     items which is needed to convert many tasklet users. To avoid
     crowding this merge window too much, this will be included in the
     next merge window. A separate pull request will be sent for the
     couple conversion patches that are currently pending.

   - Waiman plugged a long-standing hole in workqueue CPU isolation
     where ordered workqueues didn't follow wq_unbound_cpumask updates.
     Ordered workqueues now follow the same rules as other unbound
     workqueues.

   - More CPU isolation improvements: Juri fixed another deficit in
     workqueue isolation where unbound rescuers don't respect
     wq_unbound_cpumask. Leonardo fixed delayed_work timers firing on
     isolated CPUs.

   - Other misc changes"

* tag 'wq-for-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (54 commits)
  workqueue: Drain BH work items on hot-unplugged CPUs
  workqueue: Introduce from_work() helper for cleaner callback declarations
  workqueue: Control intensive warning threshold through cmdline
  workqueue: Make @flags handling consistent across set_work_data() and friends
  workqueue: Remove clear_work_data()
  workqueue: Factor out work_grab_pending() from __cancel_work_sync()
  workqueue: Clean up enum work_bits and related constants
  workqueue: Introduce work_cancel_flags
  workqueue: Use variable name irq_flags for saving local irq flags
  workqueue: Reorganize flush and cancel[_sync] functions
  workqueue: Rename __cancel_work_timer() to __cancel_timer_sync()
  workqueue: Use rcu_read_lock_any_held() instead of rcu_read_lock_held()
  workqueue: Cosmetic changes
  workqueue, irq_work: Build fix for !CONFIG_IRQ_WORK
  workqueue: Fix queue_work_on() with BH workqueues
  async: Use a dedicated unbound workqueue with raised min_active
  workqueue: Implement workqueue_set_min_active()
  workqueue: Fix kernel-doc comment of unplug_oldest_pwq()
  workqueue: Bind unbound workqueue rescuer to wq_unbound_cpumask
  kernel/workqueue: Let rescuers follow unbound wq cpumask changes
  ...
  • [D] Documentation/admin-guide/kernel-parameters.txt
Merge branch 'pm-cpufreq' 2024-03-11T14:29:59Z Rafael J. Wysocki rafael.j.wysocki@intel.com Rafael J. Wysocki rafael.j.wysocki@intel.com 2024-03-11T14:29:59Z http://git.samba.org/samba.git/?p=sfrench/cifs-2.6.git;a=commitdiff;h=32b88f59287ad895814cf0f4673047cf742791ad
Merge branch 'pm-cpufreq'

Merge cpufreq changes for 6.9-rc1:

 - Enable preferred core support in the amd-pstate cpufreq driver (Meng
   Li).

 - Fix min_perf assignment in amd_pstate_adjust_perf() and make the
   min/max limit perf values in amd-pstate always stay within the
   (highest perf, lowest perf) range (Tor Vic, Meng Li).

 - Change default transition delay in cpufreq to 2ms (Qais Yousef).

 - Drop long-unused cpudata::prev_cummulative_iowait from the
   intel_pstate cpufreq driver (Jiri Slaby).

 - Allow intel_pstate to assign model-specific values to strings used in
   the EPP sysfs interface and make it do so on Meteor Lake (Srinivas
   Pandruvada).

 - Remove references to 10ms minimum sampling rate from comments in the
   cpufreq code (Pierre Gondois).

 - Prevent scaling_cur_freq from exceeding scaling_max_freq when the
   latter is an inefficient frequency (Shivnandan Kumar).

 - Honour transition_latency over transition_delay_us in cpufreq (Qais
   Yousef).

 - Stop unregistering cpufreq cooling on CPU hot-remove (Viresh Kumar).

 - General enhancements / cleanups to ARM cpufreq drivers (tianyu2,
   NĂ­colas F. R. A. Prado, Erick Archer, Arnd Bergmann, Anastasia
   Belova).

 - Update cpufreq-dt-platdev to block/approve devices (Richard Acayan).

 - Make the SCMI cpufreq driver get a transition delay value from
   firmware (Pierre Gondois).

* pm-cpufreq: (28 commits)
  cpufreq: scmi: Set transition_delay_us
  firmware: arm_scmi: Populate fast channel rate_limit
  firmware: arm_scmi: Populate perf commands rate_limit
  cpufreq: Don't unregister cpufreq cooling on CPU hotplug
  cpufreq: Honour transition_latency over transition_delay_us
  cpufreq: Limit resolving a frequency to policy min/max
  cpufreq: amd-pstate: adjust min/max limit perf
  cpufreq: Remove references to 10ms min sampling rate
  cpufreq: intel_pstate: Update default EPPs for Meteor Lake
  cpufreq: intel_pstate: Allow model specific EPPs
  cpufreq: qcom-hw: add CONFIG_COMMON_CLK dependency
  cpufreq: dt-platdev: block SDM670 in cpufreq-dt-platdev
  cpufreq: intel_pstate: remove cpudata::prev_cummulative_iowait
  cpufreq: Change default transition delay to 2ms
  cpufreq: amd-pstate: Fix min_perf assignment in amd_pstate_adjust_perf()
  Documentation: PM: amd-pstate: Fix section title underline
  Documentation: introduce amd-pstate preferrd core mode kernel command line options
  Documentation: amd-pstate: introduce amd-pstate preferred core
  cpufreq: amd-pstate: Update amd-pstate preferred core ranking dynamically
  ACPI: cpufreq: Add highest perf change notification
  ...
  • [D] Documentation/admin-guide/kernel-parameters.txt
Merge branches 'rcu-doc.2024.02.14a', 'rcu-nocb.2024.02.14a', 'rcu-exp.2024.02.14a... 2024-02-27T01:37:25Z Boqun Feng boqun.feng@gmail.com Boqun Feng boqun.feng@gmail.com 2024-02-27T01:37:25Z http://git.samba.org/samba.git/?p=sfrench/cifs-2.6.git;a=commitdiff;h=3add00be5fe5810d7aa5ec3af8b6a245ef33144b
Merge branches 'rcu-doc.2024.02.14a', 'rcu-nocb.2024.02.14a', 'rcu-exp.2024.02.14a', 'rcu-tasks.2024.02.26a' and 'rcu-misc.2024.02.14a' into rcu.2024.02.26a
  • [D] Documentation/admin-guide/kernel-parameters.txt
drm/edid/firmware: Remove built-in EDIDs 2024-02-21T09:26:36Z Maxime Ripard mripard@kernel.org Maxime Ripard mripard@kernel.org 2024-02-21T09:26:36Z http://git.samba.org/samba.git/?p=sfrench/cifs-2.6.git;a=commitdiff;h=89ac522d4507126d353834973ddbbf7b6acfdeef
drm/edid/firmware: Remove built-in EDIDs

The EDID firmware loading mechanism introduced a few built-in EDIDs that
could be forced on any connector, bypassing the EDIDs it exposes.

While convenient, this limited set of EDIDs doesn't take into account
the connector type, and we can end up with an EDID that is completely
invalid for a given connector.

For example, the edid/800x600.bin file matches the following EDID:

  edid-decode (hex):

  00 ff ff ff ff ff ff 00 31 d8 00 00 00 00 00 00
  05 16 01 03 6d 1b 14 78 ea 5e c0 a4 59 4a 98 25
  20 50 54 01 00 00 45 40 01 01 01 01 01 01 01 01
  01 01 01 01 01 01 a0 0f 20 00 31 58 1c 20 28 80
  14 00 15 d0 10 00 00 1e 00 00 00 ff 00 4c 69 6e
  75 78 20 23 30 0a 20 20 20 20 00 00 00 fd 00 3b
  3d 24 26 05 00 0a 20 20 20 20 20 20 00 00 00 fc
  00 4c 69 6e 75 78 20 53 56 47 41 0a 20 20 00 c2

  ----------------

  Block 0, Base EDID:
    EDID Structure Version & Revision: 1.3
    Vendor & Product Identification:
      Manufacturer: LNX
      Model: 0
      Made in: week 5 of 2012
    Basic Display Parameters & Features:
      Analog display
      Signal Level Standard: 0.700 : 0.000 : 0.700 V p-p
      Blank level equals black level
      Sync: Separate Composite Serration
      Maximum image size: 27 cm x 20 cm
      Gamma: 2.20
      DPMS levels: Standby Suspend Off
      RGB color display
      First detailed timing is the preferred timing
    Color Characteristics:
      Red  : 0.6416, 0.3486
      Green: 0.2919, 0.5957
      Blue : 0.1474, 0.1250
      White: 0.3125, 0.3281
    Established Timings I & II:
      DMT 0x09:   800x600    60.316541 Hz   4:3     37.879 kHz     40.000000 MHz
    Standard Timings:
      DMT 0x09:   800x600    60.316541 Hz   4:3     37.879 kHz     40.000000 MHz
    Detailed Timing Descriptors:
      DTD 1:   800x600    60.316541 Hz   4:3     37.879 kHz     40.000000 MHz (277 mm x 208 mm)
                   Hfront   40 Hsync 128 Hback   88 Hpol P
                   Vfront    1 Vsync   4 Vback   23 Vpol P
      Display Product Serial Number: 'Linux #0'
      Display Range Limits:
        Monitor ranges (GTF): 59-61 Hz V, 36-38 kHz H, max dotclock 50 MHz
      Display Product Name: 'Linux SVGA'
  Checksum: 0xc2

So, an analog monitor EDID. However, if the connector was an HDMI
monitor for example, it breaks the HDMI specification that requires,
among other things, a digital display, the VIC 1 mode and an HDMI Forum
Vendor Specific Data Block in an CTA-861 extension.

We thus end up with a completely invalid EDID, which thus might confuse
HDMI-related code that could parse it.

After some discussions on IRC, we identified mainly two ways to fix
this:

  - We can either create more EDIDs for each connector type to provide
    a built-in EDID that matches the resolution passed in the name, and
    still be a sensible EDID for that connector type;

  - Or we can just prevent the EDID to be exposed to userspace if it's
    built-in.

Or possibly both.

However, the conclusion was that maybe we just don't need the built-in
EDIDs at all and we should just get rid of them. So here we are.

Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240221092636.691701-1-mripard@kernel.org
  • [D] Documentation/admin-guide/kernel-parameters.txt
panic: add option to dump blocked tasks in panic_print 2024-02-02T13:20:42Z Feng Tang feng.tang@intel.com Andrew Morton akpm@linux-foundation.org 2024-02-02T13:20:42Z http://git.samba.org/samba.git/?p=sfrench/cifs-2.6.git;a=commitdiff;h=2e3fc6ca521499a985a1829a21759ac25359c0f3
panic: add option to dump blocked tasks in panic_print

For debugging kernel panics and other bugs, there is already an option of
panic_print to dump all tasks' call stacks.  On today's large servers
running many containers, there could be thousands of tasks or more, and
this will print out huge amount of call stacks, taking a lot of time (for
serial console which is main target user case of panic_print).

And in many cases, only those several tasks being blocked are key for the
panic, so add an option to only dump blocked tasks' call stacks.

[akpm@linux-foundation.org: clarify documentation a little]
Link: https://lkml.kernel.org/r/20240202132042.3609657-1-feng.tang@intel.com
Signed-off-by: Feng Tang <feng.tang@intel.com>
Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
  • [D] Documentation/admin-guide/kernel-parameters.txt