linux-stable.git/include/linux/blkdev.h, branch v6.12.4

block: always verify unfreeze lock on the owner task

2024-12-05T13:03:10+00:00

commit 6a78699838a0ddeed3620ddf50c1521f1fe1e811 upstream.

commit f1be1788a32e ("block: model freeze & enter queue as lock for
supporting lockdep") tries to apply lockdep for verifying freeze &
unfreeze. However, the verification is only done the outmost freeze and
unfreeze. This way is actually not correct because q->mq_freeze_depth
still may drop to zero on other task instead of the freeze owner task.

Fix this issue by always verifying the last unfreeze lock on the owner
task context, and make sure both the outmost freeze & unfreeze are
verified in the current task.

Fixes: f1be1788a32e ("block: model freeze & enter queue as lock for supporting lockdep")
Signed-off-by: Ming Lei 
Link: https://lore.kernel.org/r/20241031133723.303835-4-ming.lei@redhat.com
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

block: return unsigned int from bdev_io_min

2024-12-05T13:03:06+00:00

[ Upstream commit 46fd48ab3ea3eb3bb215684bd66ea3d260b091a9 ]

The underlying limit is defined as an unsigned int, so return that from
bdev_io_min as well.

Fixes: ac481c20ef8f ("block: Topology ioctls")
Signed-off-by: Christoph Hellwig 
Reviewed-by: Martin K. Petersen 
Reviewed-by: John Garry 
Link: https://lore.kernel.org/r/20241119072602.1059488-1-hch@lst.de
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

block: model freeze & enter queue as lock for supporting lockdep

2024-12-05T13:03:05+00:00

[ Upstream commit f1be1788a32e8fa63416ad4518bbd1a85a825c9d ]

Recently we got several deadlock report[1][2][3] caused by
blk_mq_freeze_queue and blk_enter_queue().

Turns out the two are just like acquiring read/write lock, so model them
as read/write lock for supporting lockdep:

1) model q->q_usage_counter as two locks(io and queue lock)

- queue lock covers sync with blk_enter_queue()

- io lock covers sync with bio_enter_queue()

2) make the lockdep class/key as per-queue:

- different subsystem has very different lock use pattern, shared lock
 class causes false positive easily

- freeze_queue degrades to no lock in case that disk state becomes DEAD
  because bio_enter_queue() won't be blocked any more

- freeze_queue degrades to no lock in case that request queue becomes dying
  because blk_enter_queue() won't be blocked any more

3) model blk_mq_freeze_queue() as acquire_exclusive & try_lock
- it is exclusive lock, so dependency with blk_enter_queue() is covered

- it is trylock because blk_mq_freeze_queue() are allowed to run
  concurrently

4) model blk_enter_queue() & bio_enter_queue() as acquire_read()
- nested blk_enter_queue() are allowed

- dependency with blk_mq_freeze_queue() is covered

- blk_queue_exit() is often called from other contexts(such as irq), and
it can't be annotated as lock_release(), so simply do it in
blk_enter_queue(), this way still covered cases as many as possible

With lockdep support, such kind of reports may be reported asap and
needn't wait until the real deadlock is triggered.

For example, lockdep report can be triggered in the report[3] with this
patch applied.

[1] occasional block layer hang when setting 'echo noop > /sys/block/sda/queue/scheduler'
https://bugzilla.kernel.org/show_bug.cgi?id=219166

[2] del_gendisk() vs blk_queue_enter() race condition
https://lore.kernel.org/linux-block/20241003085610.GK11458@google.com/

[3] queue_freeze & queue_enter deadlock in scsi
https://lore.kernel.org/linux-block/ZxG38G9BuFdBpBHZ@fedora/T/#u

Reviewed-by: Christoph Hellwig 
Signed-off-by: Ming Lei 
Link: https://lore.kernel.org/r/20241025003722.3630252-4-ming.lei@redhat.com
Signed-off-by: Jens Axboe 
Stable-dep-of: 3802f73bd807 ("block: fix uaf for flush rq while iterating tags")
Signed-off-by: Sasha Levin

block: Remove unused blk_limits_io_{min,opt}

2024-09-20T06:19:48+00:00

blk_limits_io_min and blk_limits_io_opt are unused since the
recent commit
  0a94a469a4f0 ("dm: stop using blk_limits_io_{min,opt}")

Remove them.

Signed-off-by: Dr. David Alan Gilbert 
Link: https://lore.kernel.org/r/20240920004817.676216-1-linux@treblig.org
Signed-off-by: Jens Axboe

Merge tag 'v6.11' into for-6.12/block

2024-09-17T14:32:53+00:00

Merge in 6.11 final to get the fix for preventing deadlocks on an
elevator switch, as there's a fixup for that patch.

* tag 'v6.11': (1788 commits)
  Linux 6.11
  Revert "KVM: VMX: Always honor guest PAT on CPUs that support self-snoop"
  pinctrl: pinctrl-cy8c95x0: Fix regcache
  cifs: Fix signature miscalculation
  mm: avoid leaving partial pfn mappings around in error case
  drm/xe/client: add missing bo locking in show_meminfo()
  drm/xe/client: fix deadlock in show_meminfo()
  drm/xe/oa: Enable Xe2+ PES disaggregation
  drm/xe/display: fix compat IS_DISPLAY_STEP() range end
  drm/xe: Fix access_ok check in user_fence_create
  drm/xe: Fix possible UAF in guc_exec_queue_process_msg
  drm/xe: Remove fence check from send_tlb_invalidation
  drm/xe/gt: Remove double include
  net: netfilter: move nf flowtable bpf initialization in nf_flow_table_module_init()
  PCI: Fix potential deadlock in pcim_intx()
  workqueue: Clear worker->pool in the worker thread context
  net: tighten bad gso csum offset check in virtio_net_hdr
  netlink: specs: mptcp: fix port endianness
  net: dpaa: Pad packets to ETH_ZLEN
  mptcp: pm: Fix uaf in __timer_delete_sync
  ...

block: constify the lim argument to queue_limits_max_zone_append_sectors

2024-08-29T10:32:32+00:00

queue_limits_max_zone_append_sectors doesn't change the lim argument,
so mark it as const.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Damien Le Moal 
Tested-by: Hans Holmberg 
Reviewed-by: Hans Holmberg 
Link: https://lore.kernel.org/r/20240826173820.1690925-3-hch@lst.de
Signed-off-by: Jens Axboe

block: Drop NULL check in bdev_write_zeroes_sectors()

2024-08-19T15:48:59+00:00

Function bdev_get_queue() must not return NULL, so drop the check in
bdev_write_zeroes_sectors().

Reviewed-by: Christoph Hellwig 
Signed-off-by: John Garry 
Reviewed-by: Martin K. Petersen 
Reviewed-by: Nitesh Shetty 
Link: https://lore.kernel.org/r/20240815163228.216051-3-john.g.garry@oracle.com
Signed-off-by: Jens Axboe

Merge tag 'for-6.11/block-20240722' of git://git.kernel.dk/linux

2024-07-22T18:32:05+00:00

Pull more block updates from Jens Axboe:

 - MD fixes via Song:
     - md-cluster fixes (Heming Zhao)
     - raid1 fix (Mateusz Jończyk)

 - s390/dasd module description (Jeff)

 - Series cleaning up and hardening the blk-mq debugfs flag handling
   (John, Christoph)

 - blk-cgroup cleanup (Xiu)

 - Error polled IO attempts if backend doesn't support it (hexue)

 - Fix for an sbitmap hang (Yang)

* tag 'for-6.11/block-20240722' of git://git.kernel.dk/linux: (23 commits)
  blk-cgroup: move congestion_count to struct blkcg
  sbitmap: fix io hung due to race on sbitmap_word::cleared
  block: avoid polling configuration errors
  block: Catch possible entries missing from rqf_name[]
  block: Simplify definition of RQF_NAME()
  block: Use enum to define RQF_x bit indexes
  block: Catch possible entries missing from cmd_flag_name[]
  block: Catch possible entries missing from alloc_policy_name[]
  block: Catch possible entries missing from hctx_flag_name[]
  block: Catch possible entries missing from hctx_state_name[]
  block: Catch possible entries missing from blk_queue_flag_name[]
  block: Make QUEUE_FLAG_x as an enum
  block: Relocate BLK_MQ_MAX_DEPTH
  block: Relocate BLK_MQ_CPU_WORK_BATCH
  block: remove QUEUE_FLAG_STOPPED
  block: Add missing entry to hctx_flag_name[]
  block: Add zone write plugging entry to rqf_name[]
  block: Add missing entries from cmd_flag_name[]
  s390/dasd: fix error checks in dasd_copy_pair_store()
  s390/dasd: add missing MODULE_DESCRIPTION() macros
  ...

block: Make QUEUE_FLAG_x as an enum

2024-07-19T15:32:49+00:00

This will allow us better keep in sync with blk_queue_flag_name[].

Signed-off-by: John Garry 
Link: https://lore.kernel.org/r/20240719112912.3830443-8-john.g.garry@oracle.com
Signed-off-by: Jens Axboe

block: remove QUEUE_FLAG_STOPPED

2024-07-19T15:32:48+00:00

QUEUE_FLAG_STOPPED is entirely unused.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Chaitanya Kulkarni 
Reviewed-by: Bart Van Assche 
Reviewed-by: Johannes Thumshirn 
Signed-off-by: John Garry 
Link: https://lore.kernel.org/r/20240719112912.3830443-5-john.g.garry@oracle.com
Signed-off-by: Jens Axboe