linux-stable.git/drivers/block/null_blk, branch v6.6.53

null_blk: fix validation of block size

2024-07-25T07:50:43+00:00

[ Upstream commit c462ecd659b5fce731f1d592285832fd6ad54053 ]

Block size should be between 512 and PAGE_SIZE and be a power of 2. The current
check does not validate this, so update the check.

Without this patch, null_blk would Oops due to a null pointer deref when
loaded with bs=1536 [1].

Link: https://lore.kernel.org/all/87wmn8mocd.fsf@metaspace.dk/

Signed-off-by: Andreas Hindborg 
Reviewed-by: Ming Lei 
Link: https://lore.kernel.org/r/20240603192645.977968-1-nmi@metaspace.dk
[axboe: remove unnecessary braces and != 0 check]
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

null_blk: Do not allow runt zone with zone capacity smaller then zone size

2024-07-11T10:49:22+00:00

[ Upstream commit b164316808ec5de391c3e7b0148ec937d32d280d ]

A zoned device with a smaller last zone together with a zone capacity
smaller than the zone size does make any sense as that does not
correspond to any possible setup for a real device:
1) For ZNS and zoned UFS devices, all zones are always the same size.
2) For SMR HDDs, all zones always have the same capacity.
In other words, if we have a smaller last runt zone, then this zone
capacity should always be equal to the zone size.

Add a check in null_init_zoned_dev() to prevent a configuration to have
both a smaller zone size and a zone capacity smaller than the zone size.

Signed-off-by: Damien Le Moal 
Reviewed-by: Niklas Cassel 
Reviewed-by: Bart Van Assche 
Link: https://lore.kernel.org/r/20240530054035.491497-2-dlemoal@kernel.org
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

null_blk: Print correct max open zones limit in null_init_zoned_dev()

2024-06-21T12:38:40+00:00

commit 233e27b4d21c3e44eb863f03e566d3a22e81a7ae upstream.

When changing the maximum number of open zones, print that number
instead of the total number of zones.

Fixes: dc4d137ee3b7 ("null_blk: add support for max open/active zone limit for zoned devices")
Cc: stable@vger.kernel.org
Signed-off-by: Damien Le Moal 
Reviewed-by: Niklas Cassel 
Link: https://lore.kernel.org/r/20240528062852.437599-1-dlemoal@kernel.org
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

null_blk: Fix the WARNING: modpost: missing MODULE_DESCRIPTION()

2024-06-12T09:12:44+00:00

[ Upstream commit 9e6727f824edcdb8fdd3e6e8a0862eb49546e1cd ]

No functional changes intended.

Fixes: f2298c0403b0 ("null_blk: multi queue aware block test driver")
Signed-off-by: Zhu Yanjun 
Reviewed-by: Chaitanya Kulkarni 
Link: https://lore.kernel.org/r/20240506075538.6064-1-yanjun.zhu@linux.dev
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

null_blk: Fix missing mutex_destroy() at module removal

2024-06-12T09:11:34+00:00

[ Upstream commit 07d1b99825f40f9c0d93e6b99d79a08d0717bac1 ]

When a mutex lock is not used any more, the function mutex_destroy
should be called to mark the mutex lock uninitialized.

Fixes: f2298c0403b0 ("null_blk: multi queue aware block test driver")
Signed-off-by: Zhu Yanjun 
Link: https://lore.kernel.org/r/20240425171635.4227-1-yanjun.zhu@linux.dev
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

null_blk: don't cap max_hw_sectors to BLK_DEF_MAX_SECTORS

2024-01-25T23:35:29+00:00

[ Upstream commit 9a9525de865410047fa962867b4fcd33943b206f ]

null_blk has some rather odd capping of the max_hw_sectors value to
BLK_DEF_MAX_SECTORS, which doesn't make sense - max_hw_sector is the
hardware limit, and BLK_DEF_MAX_SECTORS despite the confusing name is the
default cap for the max_sectors field used for normal file system I/O.

Remove all the capping, and simply leave it to the block layer or
user to take up or not all of that for file system I/O.

Fixes: ea17fd354ca8 ("null_blk: Allow controlling max_hw_sectors limit")
Signed-off-by: Christoph Hellwig 
Link: https://lore.kernel.org/r/20231227092305.279567-2-hch@lst.de
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

null_blk: fix poll request timeout handling

2023-09-01T14:18:25+00:00

When doing io_uring benchmark on /dev/nullb0, it's easy to crash the
kernel if poll requests timeout triggered, as reported by David. [1]

BUG: kernel NULL pointer dereference, address: 0000000000000008
Workqueue: kblockd blk_mq_timeout_work
RIP: 0010:null_timeout_rq+0x4e/0x91
Call Trace:
 ? null_timeout_rq+0x4e/0x91
 blk_mq_handle_expired+0x31/0x4b
 bt_iter+0x68/0x84
 ? bt_tags_iter+0x81/0x81
 __sbitmap_for_each_set.constprop.0+0xb0/0xf2
 ? __blk_mq_complete_request_remote+0xf/0xf
 bt_for_each+0x46/0x64
 ? __blk_mq_complete_request_remote+0xf/0xf
 ? percpu_ref_get_many+0xc/0x2a
 blk_mq_queue_tag_busy_iter+0x14d/0x18e
 blk_mq_timeout_work+0x95/0x127
 process_one_work+0x185/0x263
 worker_thread+0x1b5/0x227

This is indeed a race problem between null_timeout_rq() and null_poll().

null_poll()				null_timeout_rq()
  spin_lock(&nq->poll_lock)
  list_splice_init(&nq->poll_list, &list)
  spin_unlock(&nq->poll_lock)

  while (!list_empty(&list))
    req = list_first_entry()
    list_del_init()
    ...
    blk_mq_add_to_batch()
    // req->rq_next = NULL
					spin_lock(&nq->poll_lock)

					// rq->queuelist->next == NULL
					list_del_init(&rq->queuelist)

					spin_unlock(&nq->poll_lock)

Fix these problems by setting requests state to MQ_RQ_COMPLETE under
nq->poll_lock protection, in which null_timeout_rq() can safely detect
this race and early return.

Note this patch just fix the kernel panic when request timeout happen.

[1] https://lore.kernel.org/all/3893581.1691785261@warthog.procyon.org.uk/

Fixes: 0a593fbbc245 ("null_blk: poll queue support")
Reported-by: David Howells 
Tested-by: David Howells 
Reviewed-by: Ming Lei 
Signed-off-by: Chengming Zhou 
Link: https://lore.kernel.org/r/20230901120306.170520-2-chengming.zhou@linux.dev
Signed-off-by: Jens Axboe

Merge branch '6.5/scsi-staging' into 6.5/scsi-fixes

2023-07-11T16:15:15+00:00

Pull in the currently staged SCSI fixes for 6.5.

Signed-off-by: Martin K. Petersen

scsi: block: nullblk: Set zone limits before revalidating zones

2023-07-06T01:58:10+00:00

In null_register_zoned_dev(), 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 
Link: https://lore.kernel.org/r/20230703024812.76778-4-dlemoal@kernel.org
Reviewed-by: Bart Van Assche 
Reviewed-by: Johannes Thumshirn 
Signed-off-by: Martin K. Petersen

null_blk: Fix: memory release when memory_backed=1

2023-06-05T22:15:35+00:00

Memory/pages are not freed, when unloading nullblk driver.

Steps to reproduce issue
  1.free -h
        total        used        free      shared  buff/cache   available
Mem:    7.8Gi       260Mi       7.1Gi       3.0Mi       395Mi       7.3Gi
Swap:      0B          0B          0B
  2.modprobe null_blk memory_backed=1
  3.dd if=/dev/urandom of=/dev/nullb0 oflag=direct bs=1M count=1000
  4.modprobe -r null_blk
  5.free -h
        total        used        free      shared  buff/cache   available
Mem:    7.8Gi       1.2Gi       6.1Gi       3.0Mi       398Mi       6.3Gi
Swap:      0B          0B          0B

Signed-off-by: Anuj Gupta 
Signed-off-by: Nitesh Shetty 
Link: https://lore.kernel.org/r/20230605062354.24785-1-nj.shetty@samsung.com
Signed-off-by: Jens Axboe