linux-stable.git/block, branch v6.3.12

block: make sure local irq is disabled when calling __blkcg_rstat_flush

2023-06-28T09:14:10+00:00

commit 9c39b7a905d84b7da5f59d80f2e455853fea7217 upstream.

When __blkcg_rstat_flush() is called from cgroup_rstat_flush*() code
path, interrupt is always disabled.

When we start to flush blkcg per-cpu stats list in __blkg_release()
for avoiding to leak blkcg_gq's reference in commit 20cb1c2fb756
("blk-cgroup: Flush stats before releasing blkcg_gq"), local irq
isn't disabled yet, then lockdep warning may be triggered because
the dependent cgroup locks may be acquired from irq(soft irq) handler.

Fix the issue by disabling local irq always.

Fixes: 20cb1c2fb756 ("blk-cgroup: Flush stats before releasing blkcg_gq")
Reported-by: Shinichiro Kawasaki 
Closes: https://lore.kernel.org/linux-block/pz2wzwnmn5tk3pwpskmjhli6g3qly7eoknilb26of376c7kwxy@qydzpvt6zpis/T/#u
Cc: stable@vger.kernel.org
Cc: Jay Shin 
Cc: Tejun Heo 
Cc: Waiman Long 
Signed-off-by: Ming Lei 
Reviewed-by: Waiman Long 
Link: https://lore.kernel.org/r/20230622084249.1208005-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

blk-cgroup: Flush stats before releasing blkcg_gq

2023-06-21T14:02:19+00:00

commit 20cb1c2fb7568a6054c55defe044311397e01ddb upstream.

As noted by Michal, the blkg_iostat_set's in the lockless list hold
reference to blkg's to protect against their removal. Those blkg's
hold reference to blkcg. When a cgroup is being destroyed,
cgroup_rstat_flush() is only called at css_release_work_fn() which
is called when the blkcg reference count reaches 0. This circular
dependency will prevent blkcg and some blkgs from being freed after
they are made offline.

It is less a problem if the cgroup to be destroyed also has other
controllers like memory that will call cgroup_rstat_flush() which will
clean up the reference count. If block is the only controller that uses
rstat, these offline blkcg and blkgs may never be freed leaking more
and more memory over time.

To prevent this potential memory leak:

- flush blkcg per-cpu stats list in __blkg_release(), when no new stat
can be added

- add global blkg_stat_lock for covering concurrent parent blkg stat
update

- don't grab bio->bi_blkg reference when adding the stats into blkcg's
per-cpu stat list since all stats are guaranteed to be consumed before
releasing blkg instance, and grabbing blkg reference for stats was the
most fragile part of original patch

Based on Waiman's patch:

https://lore.kernel.org/linux-block/20221215033132.230023-3-longman@redhat.com/

Fixes: 3b8cc6298724 ("blk-cgroup: Optimize blkcg_rstat_flush()")
Cc: stable@vger.kernel.org
Reported-by: Jay Shin 
Acked-by: Tejun Heo 
Cc: Waiman Long 
Cc: mkoutny@suse.com
Cc: Yosry Ahmed 
Signed-off-by: Ming Lei 
Link: https://lore.kernel.org/r/20230609234249.1412858-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

blk-mq: fix blk_mq_hw_ctx active request accounting

2023-06-14T09:17:02+00:00

[ Upstream commit ddad59331a4e16088468ca0ad228a9fe32d7955a ]

The nr_active counter continues to increase over time which causes the
blk_mq_get_tag to hang until the thread is rescheduled to a different
core despite there are still tags available.

kernel-stack

  INFO: task inboundIOReacto:3014879 blocked for more than 2 seconds
  Not tainted 6.1.15-amd64 #1 Debian 6.1.15~debian11
  "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  task:inboundIOReacto state:D stack:0  pid:3014879 ppid:4557 flags:0x00000000
    Call Trace:
    
    __schedule+0x351/0xa20
    scheduler+0x5d/0xe0
    io_schedule+0x42/0x70
    blk_mq_get_tag+0x11a/0x2a0
    ? dequeue_task_stop+0x70/0x70
    __blk_mq_alloc_requests+0x191/0x2e0

kprobe output showing RQF_MQ_INFLIGHT bit is not cleared before
__blk_mq_free_request being called.

  320    320  kworker/29:1H __blk_mq_free_request rq_flags 0x220c0 in-flight 1
         b'__blk_mq_free_request+0x1 [kernel]'
         b'bt_iter+0x50 [kernel]'
         b'blk_mq_queue_tag_busy_iter+0x318 [kernel]'
         b'blk_mq_timeout_work+0x7c [kernel]'
         b'process_one_work+0x1c4 [kernel]'
         b'worker_thread+0x4d [kernel]'
         b'kthread+0xe6 [kernel]'
         b'ret_from_fork+0x1f [kernel]'

Signed-off-by: Tian Lan 
Fixes: 2e315dc07df0 ("blk-mq: grab rq->refcount before calling ->fn in blk_mq_tagset_busy_iter")
Reviewed-by: Ming Lei 
Link: https://lore.kernel.org/r/20230513221227.497327-1-tilan7663@gmail.com
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

block: fix revalidate performance regression

2023-06-09T08:48:18+00:00

commit 47fe1c3064c6bc1bfa3c032ff78e603e5dd6e5bc upstream.

The scsi driver function sd_read_block_characteristics() always calls
disk_set_zoned() to a disk zoned model correctly, in case the device
model changed. This is done even for regular disks to set the zoned
model to BLK_ZONED_NONE and free any zone related resources if the drive
previously was zoned.

This behavior significantly impact the time it takes to revalidate disks
on a large system as the call to disk_clear_zone_settings() done from
disk_set_zoned() for the BLK_ZONED_NONE case results in the device
request queued to be frozen, even if there are no zone resources to
free.

Avoid this overhead for non-zoned devices by not calling
disk_clear_zone_settings() in disk_set_zoned() if the device model
was already set to BLK_ZONED_NONE, which is always the case for regular
devices.

Reported by: Brian Bunker 

Fixes: 508aebb80527 ("block: introduce blk_queue_clear_zone_settings()")
Cc: stable@vger.kernel.org
Signed-off-by: Damien Le Moal 
Reviewed-by: Ming Lei 
Link: https://lore.kernel.org/r/20230529073237.1339862-1-dlemoal@kernel.org
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

block: Deny writable memory mapping if block is read-only

2023-06-09T08:48:10+00:00

[ Upstream commit 69baa3a623fd2e58624f24f2f23d46f87b817c93 ]

User should not be able to write block device if it is read-only at
block level (e.g force_ro attribute). This is ensured in the regular
fops write operation (blkdev_write_iter) but not when writing via
user mapping (mmap), allowing user to actually write a read-only
block device via a PROT_WRITE mapping.

Example: This can lead to integrity issue of eMMC boot partition
(e.g mmcblk0boot0) which is read-only by default.

To fix this issue, simply deny shared writable mapping if the block
is readonly.

Note: Block remains writable if switch to read-only is performed
after the initial mapping, but this is expected behavior according
to commit a32e236eb93e ("Partially revert "block: fail op_is_write()
requests to read-only partitions"")'.

Signed-off-by: Loic Poulain 
Reviewed-by: Christoph Hellwig 
Link: https://lore.kernel.org/r/20230510074223.991297-1-loic.poulain@linaro.org
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

blk-mq: fix race condition in active queue accounting

2023-06-05T07:29:43+00:00

[ Upstream commit 3e94d54e83cafd2b562bb6d15bb2f72d76200fb5 ]

If multiple CPUs are sharing the same hardware queue, it can
cause leak in the active queue counter tracking when __blk_mq_tag_busy()
is executed simultaneously.

Fixes: ee78ec1077d3 ("blk-mq: blk_mq_tag_busy is no need to return a value")
Signed-off-by: Tian Lan 
Reviewed-by: Ming Lei 
Reviewed-by: Damien Le Moal 
Reviewed-by: John Garry 
Link: https://lore.kernel.org/r/20230522210555.794134-1-tilan7663@gmail.com
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

blk-wbt: fix that wbt can't be disabled by default

2023-06-05T07:29:43+00:00

[ Upstream commit 8a2b20a997a3779ae9fcae268f2959eb82ec05a1 ]

commit b11d31ae01e6 ("blk-wbt: remove unnecessary check in
wbt_enable_default()") removes the checking of CONFIG_BLK_WBT_MQ by
mistake, which is used to control enable or disable wbt by default.

Fix the problem by adding back the checking. This patch also do a litter
cleanup to make related code more readable.

Fixes: b11d31ae01e6 ("blk-wbt: remove unnecessary check in wbt_enable_default()")
Reported-by: Lukas Bulwahn 
Link: https://lore.kernel.org/lkml/CAKXUXMzfKq_J9nKHGyr5P5rvUETY4B-fxoQD4sO+NYjFOfVtZA@mail.gmail.com/t/
Signed-off-by: Yu Kuai 
Reviewed-by: Christoph Hellwig 
Link: https://lore.kernel.org/r/20230522121854.2928880-1-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

block: fix bio-cache for passthru IO

2023-05-30T13:17:22+00:00

commit 46930b7cc7727271c9c27aac1fdc97a8645e2d00 upstream.

commit <8af870aa5b847> ("block: enable bio caching use for passthru IO")
introduced bio-cache for passthru IO. In case when nr_vecs are greater
than BIO_INLINE_VECS, bio and bvecs are allocated from mempool (instead
of percpu cache) and REQ_ALLOC_CACHE is cleared. This causes the side
effect of not freeing bio/bvecs into mempool on completion.

This patch lets the passthru IO fallback to allocation using bio_kmalloc
when nr_vecs are greater than BIO_INLINE_VECS. The corresponding bio
is freed during call to blk_mq_map_bio_put during completion.

Cc: stable@vger.kernel.org # 6.1
fixes <8af870aa5b847> ("block: enable bio caching use for passthru IO")

Signed-off-by: Anuj Gupta 
Signed-off-by: Kanchan Joshi 
Link: https://lore.kernel.org/r/20230523111709.145676-1-anuj20.g@samsung.com
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

block, bfq: Fix division by zero error on zero wsum

2023-05-24T16:30:06+00:00

[ Upstream commit e53413f8deedf738a6782cc14cc00bd5852ccf18 ]

When the weighted sum is zero the calculation of limit causes
a division by zero error. Fix this by continuing to the next level.

This was discovered by running as root:

stress-ng --ioprio 0

Fixes divison by error oops:

[  521.450556] divide error: 0000 [#1] SMP NOPTI
[  521.450766] CPU: 2 PID: 2684464 Comm: stress-ng-iopri Not tainted 6.2.1-1280.native #1
[  521.451117] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.1-0-g3208b098f51a-prebuilt.qemu.org 04/01/2014
[  521.451627] RIP: 0010:bfqq_request_over_limit+0x207/0x400
[  521.451875] Code: 01 48 8d 0c c8 74 0b 48 8b 82 98 00 00 00 48 8d 0c c8 8b 85 34 ff ff ff 48 89 ca 41 0f af 41 50 48 d1 ea 48 98 48 01 d0 31 d2 <48> f7 f1 41 39 41 48 89 85 34 ff ff ff 0f 8c 7b 01 00 00 49 8b 44
[  521.452699] RSP: 0018:ffffb1af84eb3948 EFLAGS: 00010046
[  521.452938] RAX: 000000000000003c RBX: 0000000000000000 RCX: 0000000000000000
[  521.453262] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffb1af84eb3978
[  521.453584] RBP: ffffb1af84eb3a30 R08: 0000000000000001 R09: ffff8f88ab8a4ba0
[  521.453905] R10: 0000000000000000 R11: 0000000000000001 R12: ffff8f88ab8a4b18
[  521.454224] R13: ffff8f8699093000 R14: 0000000000000001 R15: ffffb1af84eb3970
[  521.454549] FS:  00005640b6b0b580(0000) GS:ffff8f88b3880000(0000) knlGS:0000000000000000
[  521.454912] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  521.455170] CR2: 00007ffcbcae4e38 CR3: 00000002e46de001 CR4: 0000000000770ee0
[  521.455491] PKRU: 55555554
[  521.455619] Call Trace:
[  521.455736]  
[  521.455837]  ? bfq_request_merge+0x3a/0xc0
[  521.456027]  ? elv_merge+0x115/0x140
[  521.456191]  bfq_limit_depth+0xc8/0x240
[  521.456366]  __blk_mq_alloc_requests+0x21a/0x2c0
[  521.456577]  blk_mq_submit_bio+0x23c/0x6c0
[  521.456766]  __submit_bio+0xb8/0x140
[  521.457236]  submit_bio_noacct_nocheck+0x212/0x300
[  521.457748]  submit_bio_noacct+0x1a6/0x580
[  521.458220]  submit_bio+0x43/0x80
[  521.458660]  ext4_io_submit+0x23/0x80
[  521.459116]  ext4_do_writepages+0x40a/0xd00
[  521.459596]  ext4_writepages+0x65/0x100
[  521.460050]  do_writepages+0xb7/0x1c0
[  521.460492]  __filemap_fdatawrite_range+0xa6/0x100
[  521.460979]  file_write_and_wait_range+0xbf/0x140
[  521.461452]  ext4_sync_file+0x105/0x340
[  521.461882]  __x64_sys_fsync+0x67/0x100
[  521.462305]  ? syscall_exit_to_user_mode+0x2c/0x1c0
[  521.462768]  do_syscall_64+0x3b/0xc0
[  521.463165]  entry_SYSCALL_64_after_hwframe+0x5a/0xc4
[  521.463621] RIP: 0033:0x5640b6c56590
[  521.464006] Code: 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 80 3d 71 70 0e 00 00 74 17 b8 4a 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c

Signed-off-by: Colin Ian King 
Link: https://lore.kernel.org/r/20230413133009.1605335-1-colin.i.king@gmail.com
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

block: Skip destroyed blkg when restart in blkg_destroy_all()

2023-05-17T12:01:40+00:00

[ Upstream commit 8176080d59e6d4ff9fc97ae534063073b4f7a715 ]

Kernel hang in blkg_destroy_all() when total blkg greater than
BLKG_DESTROY_BATCH_SIZE, because of not removing destroyed blkg in
blkg_list. So the size of blkg_list is same after destroying a
batch of blkg, and the infinite 'restart' occurs.

Since blkg should stay on the queue list until blkg_free_workfn(),
skip destroyed blkg when restart a new round, which will solve this
kernel hang issue and satisfy the previous will to restart.

Reported-by: Xiangfei Ma 
Tested-by: Xiangfei Ma 
Tested-by: Farrah Chen 
Signed-off-by: Tao Su 
Fixes: f1c006f1c685 ("blk-cgroup: synchronize pd_free_fn() from blkg_free_workfn() and blkcg_deactivate_policy()")
Suggested-and-reviewed-by: Yu Kuai 
Link: https://lore.kernel.org/r/20230428045149.1310073-1-tao1.su@linux.intel.com
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin