Merge tag 'for-6.9/block-20240310' of git://git.kernel.dk/linux Pull block updates from Jens Axboe: - MD pull requests via Song: - Cleanup redundant checks (Yu Kuai) - Remove deprecated headers (Marc Zyngier, Song Liu) - Concurrency fixes (Li Lingfeng) - Memory leak fix (Li Nan) - Refactor raid1 read_balance (Yu Kuai, Paul Luse) - Clean up and fix for md_ioctl (Li Nan) - Other small fixes (Gui-Dong Han, Heming Zhao) - MD atomic limits (Christoph) - NVMe pull request via Keith: - RDMA target enhancements (Max) - Fabrics fixes (Max, Guixin, Hannes) - Atomic queue_limits usage (Christoph) - Const use for class_register (Ricardo) - Identification error handling fixes (Shin'ichiro, Keith) - Improvement and cleanup for cached request handling (Christoph) - Moving towards atomic queue limits. Core changes and driver bits so far (Christoph) - Fix UAF issues in aoeblk (Chun-Yi) - Zoned fix and cleanups (Damien) - s390 dasd cleanups and fixes (Jan, Miroslav) - Block issue timestamp caching (me) - noio scope guarding for zoned IO (Johannes) - block/nvme PI improvements (Kanchan) - Ability to terminate long running discard loop (Keith) - bdev revalidation fix (Li) - Get rid of old nr_queues hack for kdump kernels (Ming) - Support for async deletion of ublk (Ming) - Improve IRQ bio recycling (Pavel) - Factor in CPU capacity for remote vs local completion (Qais) - Add shared_tags configfs entry for null_blk (Shin'ichiro - Fix for a regression in page refcounts introduced by the folio unification (Tony) - Misc fixes and cleanups (Arnd, Colin, John, Kunwu, Li, Navid, Ricardo, Roman, Tang, Uwe) * tag 'for-6.9/block-20240310' of git://git.kernel.dk/linux: (221 commits) block: partitions: only define function mac_fix_string for CONFIG_PPC_PMAC block/swim: Convert to platform remove callback returning void cdrom: gdrom: Convert to platform remove callback returning void block: remove disk_stack_limits md: remove mddev->queue md: don't initialize queue limits md/raid10: use the atomic queue limit update APIs md/raid5: use the atomic queue limit update APIs md/raid1: use the atomic queue limit update APIs md/raid0: use the atomic queue limit update APIs md: add queue limit helpers md: add a mddev_is_dm helper md: add a mddev_add_trace_msg helper md: add a mddev_trace_remap helper bcache: move calculation of stripe_size and io_opt into bcache_device_init virtio_blk: Do not use disk_set_max_open/active_zones() aoe: fix the potential use-after-free problem in aoecmd_cfg_pkts block: move capacity validation to blkpg_do_ioctl() block: prevent division by zero in blk_rq_stat_sum() drbd: atomically update queue limits in drbd_reconsider_queue_parameters ...
virtio_blk: Do not use disk_set_max_open/active_zones() In virtblk_read_zoned_limits(), setting a zoned block device maximum number of open and active zones using the functions disk_set_max_open_zones() and disk_set_max_active_zones() is incorrect as setting the limits for the request queue is now done atomically when the gendisk is created (with blk_mq_alloc_disk()). The value set by the disk_set_max_open/active_zones() functions will be overwritten. Fix this by setting the maximum number of open and active zones directly in the queue_limits structure passed to virtblk_read_zoned_limits(). Fixes: 8b837256560c ("virtio_blk: pass queue_limits to blk_mq_alloc_disk") Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20240301192639.410183-2-dlemoal@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
virtio_blk: pass queue_limits to blk_mq_alloc_disk Call virtblk_read_limits and most of virtblk_probe_zoned_device before allocating the gendisk and thus request_queue and make them read into a queue_limits structure instead. Pass this initialized queue_limits to blk_mq_alloc_disk to set the queue up with the right parameters from the start and only leave a few final touches for zoned devices to be done just before adding the disk. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Link: https://lore.kernel.org/r/20240213073425.1621680-13-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
virtio_blk: split virtblk_probe Split out a virtblk_read_limits helper that just reads the various queue limits to separate it from the higher level probing logic. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Link: https://lore.kernel.org/r/20240213073425.1621680-12-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
block: pass a queue_limits argument to blk_mq_alloc_disk Pass a queue_limits to blk_mq_alloc_disk and apply it if non-NULL. This will allow allocating queues with valid queue limits instead of setting the values one at a time later. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Keith Busch <kbusch@kernel.org> Reviewed-by: John Garry <john.g.garry@oracle.com> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Link: https://lore.kernel.org/r/20240213073425.1621680-11-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
virtio-blk: Ensure no requests in virtqueues before deleting vqs. Ensure no remaining requests in virtqueues before resetting vdev and deleting virtqueues. Otherwise these requests will never be completed. It may cause the system to become unresponsive. Function blk_mq_quiesce_queue() can ensure that requests have become in_flight status, but it cannot guarantee that requests have been processed by the device. Virtqueues should never be deleted before all requests become complete status. Function blk_mq_freeze_queue() ensure that all requests in virtqueues become complete status. And no requests can enter in virtqueues. Signed-off-by: Yi Sun <yi.sun@unisoc.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Link: https://lore.kernel.org/r/20240129085250.1550594-1-yi.sun@unisoc.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
Merge tag 'for-6.8/block-2024-01-18' of git://git.kernel.dk/linux Pull block fixes from Jens Axboe: - NVMe pull request via Keith: - tcp, fc, and rdma target fixes (Maurizio, Daniel, Hannes, Christoph) - discard fixes and improvements (Christoph) - timeout debug improvements (Keith, Max) - various cleanups (Daniel, Max, Giuxen) - trace event string fixes (Arnd) - shadow doorbell setup on reset fix (William) - a write zeroes quirk for SK Hynix (Jim) - MD pull request via Song: - Sparse warning since v6.0 (Bart) - /proc/mdstat regression since v6.7 (Yu Kuai) - Use symbolic error value (Christian) - IO Priority documentation update (Christian) - Fix for accessing queue limits without having entered the queue (Christoph, me) - Fix for loop dio support (Christoph) - Move null_blk off deprecated ida interface (Christophe) - Ensure nbd initializes full msghdr (Eric) - Fix for a regression with the folio conversion, which is now easier to hit because of an unrelated change (Matthew) - Remove redundant check in virtio-blk (Li) - Fix for a potential hang in sbitmap (Ming) - Fix for partial zone appending (Damien) - Misc changes and fixes (Bart, me, Kemeng, Dmitry) * tag 'for-6.8/block-2024-01-18' of git://git.kernel.dk/linux: (45 commits) Documentation: block: ioprio: Update schedulers loop: fix the the direct I/O support check when used on top of block devices blk-mq: Remove the hctx 'run' debugfs attribute nbd: always initialize struct msghdr completely block: Fix iterating over an empty bio with bio_for_each_folio_all block: bio-integrity: fix kcalloc() arguments order virtio_blk: remove duplicate check if queue is broken in virtblk_done sbitmap: remove stale comment in sbq_calc_wake_batch block: Correct a documentation comment in blk-cgroup.c null_blk: Remove usage of the deprecated ida_simple_xx() API block: ensure we hold a queue reference when using queue limits blk-mq: rename blk_mq_can_use_cached_rq block: print symbolic error name instead of error code blk-mq: fix IO hang from sbitmap wakeup race nvmet-rdma: avoid circular locking dependency on install_queue() nvmet-tcp: avoid circular locking dependency on install_queue() nvme-pci: set doorbell config before unquiescing block: fix partial zone append completion handling in req_bio_endio() block/iocost: silence warning on 'last_period' potentially being unused md/raid1: Use blk_opf_t for read and write operations ...
virtio_blk: remove duplicate check if queue is broken in virtblk_done virtqueue_enable_cb() will call virtqueue_poll() which will check if queue is broken at beginning, so remove the virtqueue_is_broken() call Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Li RongQing <lirongqing@baidu.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Merge tag 'for-6.8/block-2024-01-08' of git://git.kernel.dk/linux Pull block updates from Jens Axboe: "Pretty quiet round this time around. This contains: - NVMe updates via Keith: - nvme fabrics spec updates (Guixin, Max) - nvme target udpates (Guixin, Evan) - nvme attribute refactoring (Daniel) - nvme-fc numa fix (Keith) - MD updates via Song: - Fix/Cleanup RCU usage from conf->disks[i].rdev (Yu Kuai) - Fix raid5 hang issue (Junxiao Bi) - Add Yu Kuai as Reviewer of the md subsystem - Remove deprecated flavors (Song Liu) - raid1 read error check support (Li Nan) - Better handle events off-by-1 case (Alex Lyakas) - Efficiency improvements for passthrough (Kundan) - Support for mapping integrity data directly (Keith) - Zoned write fix (Damien) - rnbd fixes (Kees, Santosh, Supriti) - Default to a sane discard size granularity (Christoph) - Make the default max transfer size naming less confusing (Christoph) - Remove support for deprecated host aware zoned model (Christoph) - Misc fixes (me, Li, Matthew, Min, Ming, Randy, liyouhong, Daniel, Bart, Christoph)" * tag 'for-6.8/block-2024-01-08' of git://git.kernel.dk/linux: (78 commits) block: Treat sequential write preferred zone type as invalid block: remove disk_clear_zoned sd: remove the !ZBC && blk_queue_is_zoned case in sd_read_block_characteristics drivers/block/xen-blkback/common.h: Fix spelling typo in comment blk-cgroup: fix rcu lockdep warning in blkg_lookup() blk-cgroup: don't use removal safe list iterators block: floor the discard granularity to the physical block size mtd_blkdevs: use the default discard granularity bcache: use the default discard granularity zram: use the default discard granularity null_blk: use the default discard granularity nbd: use the default discard granularity ubd: use the default discard granularity block: default the discard granularity to sector size bcache: discard_granularity should not be smaller than a sector block: remove two comments in bio_split_discard block: rename and document BLK_DEF_MAX_SECTORS loop: don't abuse BLK_DEF_MAX_SECTORS aoe: don't abuse BLK_DEF_MAX_SECTORS null_blk: don't cap max_hw_sectors to BLK_DEF_MAX_SECTORS ...
block: simplify disk_set_zoned Only use disk_set_zoned to actually enable zoned device support. For clearing it, call disk_clear_zoned, which is renamed from disk_clear_zone_settings and now directly clears the zoned flag as well. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20231217165359.604246-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
block: remove support for the host aware zone model When zones were first added the SCSI and ATA specs, two different models were supported (in addition to the drive managed one that is invisible to the host): - host managed where non-conventional zones there is strict requirement to write at the write pointer, or else an error is returned - host aware where a write point is maintained if writes always happen at it, otherwise it is left in an under-defined state and the sequential write preferred zones behave like conventional zones (probably very badly performing ones, though) Not surprisingly this lukewarm model didn't prove to be very useful and was finally removed from the ZBC and SBC specs (NVMe never implemented it). Due to to the easily disappearing write pointer host software could never rely on the write pointer to actually be useful for say recovery. Fortunately only a few HDD prototypes shipped using this model which never made it to mass production. Drop the support before it is too late. Note that any such host aware prototype HDD can still be used with Linux as we'll now treat it as a conventional HDD. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20231217165359.604246-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
virtio_blk: remove the broken zone revalidation support virtblk_revalidate_zones is called unconditionally from virtblk_config_changed_work from the virtio config_changed callback. virtblk_revalidate_zones is a bit odd in that it re-clears the zoned state for host aware or non-zoned devices, which isn't needed unless the zoned mode changed - but a zone mode change to a host managed model isn't handled at all, and virtio_blk also doesn't handle any other config change except for a capacity change is handled (and even if it was the upper layers above virtio_blk wouldn't handle it very well). But even the useful case of a size change that would add or remove zones isn't handled properly as blk_revalidate_disk_zones expects the device capacity to cover all zones, but the capacity is only updated after virtblk_revalidate_zones. As this code appears to be entirely untested and is getting in the way remove it for now, but it can be readded in a fixed version with proper test coverage if needed. Fixes: 95bfec41bd3d ("virtio-blk: add support for zoned block devices") Fixes: f1ba4e674feb ("virtio-blk: fix to match virtio spec") Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20231217165359.604246-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
virtio_blk: cleanup zoned device probing Move reading and checking the zoned model from virtblk_probe_zoned_device into the caller, leaving only the code to perform the actual setup for host managed zoned devices in virtblk_probe_zoned_device. This allows to share the model reading and sharing between builds with and without CONFIG_BLK_DEV_ZONED, and improve it for the !CONFIG_BLK_DEV_ZONED case. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20231217165359.604246-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
virtio_blk: fix snprintf truncation compiler warning Commit 4e0400525691 ("virtio-blk: support polling I/O") triggers the following gcc 13 W=1 warnings: drivers/block/virtio_blk.c: In function ‘init_vq’: drivers/block/virtio_blk.c:1077:68: warning: ‘%d’ directive output may be truncated writing between 1 and 11 bytes into a region of size 7 [-Wformat-truncation=] 1077 | snprintf(vblk->vqs[i].name, VQ_NAME_LEN, "req_poll.%d", i); | ^~ drivers/block/virtio_blk.c:1077:58: note: directive argument in the range [-2147483648, 65534] 1077 | snprintf(vblk->vqs[i].name, VQ_NAME_LEN, "req_poll.%d", i); | ^~~~~~~~~~~~~ drivers/block/virtio_blk.c:1077:17: note: ‘snprintf’ output between 11 and 21 bytes into a destination of size 16 1077 | snprintf(vblk->vqs[i].name, VQ_NAME_LEN, "req_poll.%d", i); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ This is a false positive because the lower bound -2147483648 is incorrect. The true range of i is [0, num_vqs - 1] where 0 < num_vqs < 65536. The code mixes int, unsigned short, and unsigned int types in addition to using "%d" for an unsigned value. Use unsigned short and "%u" consistently to solve the compiler warning. Cc: Suwan Kim <suwan.kim027@gmail.com> Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202312041509.DIyvEt9h-lkp@intel.com/ Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20231204140743.1487843-1-stefanha@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Merge tag 'for_linus' of git://git./linux/kernel/git/mst/vhost Pull virtio updates from Michael Tsirkin: "vhost,virtio,vdpa: features, fixes, cleanups. vdpa/mlx5: - VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK - new maintainer vdpa: - support for vq descriptor mappings - decouple reset of iotlb mapping from device reset and fixes, cleanups all over the place" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (34 commits) vdpa_sim: implement .reset_map support vdpa/mlx5: implement .reset_map driver op vhost-vdpa: clean iotlb map during reset for older userspace vdpa: introduce .compat_reset operation callback vhost-vdpa: introduce IOTLB_PERSIST backend feature bit vhost-vdpa: reset vendor specific mapping to initial state in .release vdpa: introduce .reset_map operation callback virtio_pci: add check for common cfg size virtio-blk: fix implicit overflow on virtio_max_dma_size virtio_pci: add build offset check for the new common cfg items virtio: add definition of VIRTIO_F_NOTIF_CONFIG_DATA feature bit vduse: make vduse_class constant vhost-scsi: Spelling s/preceeding/preceding/g virtio: kdoc for struct virtio_pci_modern_device vdpa: Update sysfs ABI documentation MAINTAINERS: Add myself as mlx5_vdpa driver virtio-balloon: correct the comment of virtballoon_migratepage() mlx5_vdpa: offer VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK vdpa/mlx5: Update cvq iotlb mapping on ASID change vdpa/mlx5: Make iotlb helper functions more generic ...
virtio-blk: fix implicit overflow on virtio_max_dma_size The following codes have an implicit conversion from size_t to u32: (u32)max_size = (size_t)virtio_max_dma_size(vdev); This may lead overflow, Ex (size_t)4G -> (u32)0. Once virtio_max_dma_size() has a larger size than U32_MAX, use U32_MAX instead. Signed-off-by: zhenwei pi <pizhenwei@bytedance.com> Message-Id: <20230904061045.510460-1-pizhenwei@bytedance.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
blk-mq: update driver tags request table when start request Now we update driver tags request table in blk_mq_get_driver_tag(), so the driver that support queue_rqs() have to update that inflight table by itself. Move it to blk_mq_start_request(), which is a better place where we setup the deadline for request timeout check. And it's just where the request becomes inflight. Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20230913151616.3164338-5-chengming.zhou@linux.dev Signed-off-by: Jens Axboe <axboe@kernel.dk>
Merge branch '6.5/scsi-staging' into 6.5/scsi-fixes Pull in the currently staged SCSI fixes for 6.5. Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
scsi: block: virtio_blk: Set zone limits before revalidating zones In virtblk_probe_zoned_device(), execute blk_queue_chunk_sectors() and blk_queue_max_zone_append_sectors() to respectively set the zoned device zone size and maximum zone append sector limit before executing blk_revalidate_disk_zones(). This is to allow the block layer zone reavlidation to check these device characteristics prior to checking all zones of the device. Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Link: https://lore.kernel.org/r/20230703024812.76778-5-dlemoal@kernel.org Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Dmitry Fomichev <dmitry.fomichev@wdc.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Revert "virtio-blk: support completion batching for the IRQ path" This reverts commit 07b679f70d73483930e8d3c293942416d9cd5c13. This change appears to have broken things... We now see applications hanging during disk accesses. e.g. multi-port virtio-blk device running in h/w (FPGA) Host running a simple 'fio' test. [global] thread=1 direct=1 ioengine=libaio norandommap=1 group_reporting=1 bs=4K rw=read iodepth=128 runtime=1 numjobs=4 time_based [job0] filename=/dev/vda [job1] filename=/dev/vdb [job2] filename=/dev/vdc ... [job15] filename=/dev/vdp i.e. 16 disks; 4 queues per disk; simple burst of 4KB reads This is repeatedly run in a loop. After a few, normally <10 seconds, fio hangs. With 64 queues (16 disks), failure occurs within a few seconds; with 8 queues (2 disks) it may take ~hour before hanging. Last message: fio-3.19 Starting 8 threads Jobs: 1 (f=1): [_(7),R(1)][68.3%][eta 03h:11m:06s] I think this means at the end of the run 1 queue was left incomplete. 'diskstats' (run while fio is hung) shows no outstanding transactions. e.g. $ cat /proc/diskstats ... 252 0 vda 1843140071 0 14745120568 712568645 0 0 0 0 0 3117947 712568645 0 0 0 0 0 0 252 16 vdb 1816291511 0 14530332088 704905623 0 0 0 0 0 3117711 704905623 0 0 0 0 0 0 ... Other stats (in the h/w, and added to the virtio-blk driver ([a]virtio_queue_rq(), [b]virtblk_handle_req(), [c]virtblk_request_done()) all agree, and show every request had a completion, and that virtblk_request_done() never gets called. e.g. PF= 0 vq=0 1 2 3 [a]request_count - 839416590 813148916 105586179 84988123 [b]completion1_count - 839416590 813148916 105586179 84988123 [c]completion2_count - 0 0 0 0 PF= 1 vq=0 1 2 3 [a]request_count - 823335887 812516140 104582672 75856549 [b]completion1_count - 823335887 812516140 104582672 75856549 [c]completion2_count - 0 0 0 0 i.e. the issue is after the virtio-blk driver. This change was introduced in kernel 6.3.0. I am seeing this using 6.3.3. If I run with an earlier kernel (5.15), it does not occur. If I make a simple patch to the 6.3.3 virtio-blk driver, to skip the blk_mq_add_to_batch()call, it does not fail. e.g. kernel 5.15 - this is OK virtio_blk.c,virtblk_done() [irq handler] if (likely(!blk_should_fake_timeout(req->q))) { blk_mq_complete_request(req); } kernel 6.3.3 - this fails virtio_blk.c,virtblk_handle_req() [irq handler] if (likely(!blk_should_fake_timeout(req->q))) { if (!blk_mq_complete_request_remote(req)) { if (!blk_mq_add_to_batch(req, iob, virtblk_vbr_status(vbr), virtblk_complete_batch)) { virtblk_request_done(req); //this never gets called... so blk_mq_add_to_batch() must always succeed } } } If I do, kernel 6.3.3 - this is OK virtio_blk.c,virtblk_handle_req() [irq handler] if (likely(!blk_should_fake_timeout(req->q))) { if (!blk_mq_complete_request_remote(req)) { virtblk_request_done(req); //force this here... if (!blk_mq_add_to_batch(req, iob, virtblk_vbr_status(vbr), virtblk_complete_batch)) { virtblk_request_done(req); //this never gets called... so blk_mq_add_to_batch() must always succeed } } } Perhaps you might like to fix/test/revert this change... Martin Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202306090826.C1fZmdMe-lkp@intel.com/ Cc: Suwan Kim <suwan.kim027@gmail.com> Tested-by: edliaw@google.com Reported-by: "Roberts, Martin" <martin.roberts@intel.com> Message-Id: <336455b4f630f329380a8f53ee8cad3868764d5c.1686295549.git.mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>