diff options
| author | Zheng Qixing <zhengqixing@huawei.com> | 2025-08-26 15:42:03 +0800 |
|---|---|---|
| committer | Mikulas Patocka <mpatocka@redhat.com> | 2025-08-26 16:46:32 +0200 |
| commit | 7f597c2cdb9d3263a6fce07c4fc0a9eaa8e8fc43 (patch) | |
| tree | f8874f731eb892e861b1cc262f263cafee26109f | |
| parent | dm-pcache: add persistent cache target in device-mapper (diff) | |
| download | linux-7f597c2cdb9d3263a6fce07c4fc0a9eaa8e8fc43.tar.gz linux-7f597c2cdb9d3263a6fce07c4fc0a9eaa8e8fc43.zip | |
dm: fix queue start/stop imbalance under suspend/load/resume races
When suspend and load run concurrently, before q->mq_ops is set in
blk_mq_init_allocated_queue(), __dm_suspend() skip dm_stop_queue(). As a
result, the queue's quiesce depth is not incremented.
Later, once table load has finished and __dm_resume() runs, which triggers
q->quiesce_depth ==0 warning in blk_mq_unquiesce_queue():
Call Trace:
<TASK>
dm_start_queue+0x16/0x20 [dm_mod]
__dm_resume+0xac/0xb0 [dm_mod]
dm_resume+0x12d/0x150 [dm_mod]
do_resume+0x2c2/0x420 [dm_mod]
dev_suspend+0x30/0x130 [dm_mod]
ctl_ioctl+0x402/0x570 [dm_mod]
dm_ctl_ioctl+0x23/0x30 [dm_mod]
Fix this by explicitly tracking whether the request queue was
stopped in __dm_suspend() via a new DMF_QUEUE_STOPPED flag.
Only call dm_start_queue() in __dm_resume() if the queue was
actually stopped.
Fixes: e70feb8b3e68 ("blk-mq: support concurrent queue quiesce/unquiesce")
Cc: stable@vger.kernel.org
Signed-off-by: Zheng Qixing <zhengqixing@huawei.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
| -rw-r--r-- | drivers/md/dm-core.h | 1 | ||||
| -rw-r--r-- | drivers/md/dm.c | 8 |
2 files changed, 6 insertions, 3 deletions
diff --git a/drivers/md/dm-core.h b/drivers/md/dm-core.h index c889332e533b..0070e4462ee2 100644 --- a/drivers/md/dm-core.h +++ b/drivers/md/dm-core.h @@ -162,6 +162,7 @@ struct mapped_device { #define DMF_SUSPENDED_INTERNALLY 7 #define DMF_POST_SUSPENDING 8 #define DMF_EMULATE_ZONE_APPEND 9 +#define DMF_QUEUE_STOPPED 10 static inline sector_t dm_get_size(struct mapped_device *md) { diff --git a/drivers/md/dm.c b/drivers/md/dm.c index a44e8c2dccee..7222f20c1a83 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -2960,8 +2960,10 @@ static int __dm_suspend(struct mapped_device *md, struct dm_table *map, * Stop md->queue before flushing md->wq in case request-based * dm defers requests to md->wq from md->queue. */ - if (dm_request_based(md)) + if (dm_request_based(md)) { dm_stop_queue(md->queue); + set_bit(DMF_QUEUE_STOPPED, &md->flags); + } flush_workqueue(md->wq); @@ -2983,7 +2985,7 @@ static int __dm_suspend(struct mapped_device *md, struct dm_table *map, if (r < 0) { dm_queue_flush(md); - if (dm_request_based(md)) + if (test_and_clear_bit(DMF_QUEUE_STOPPED, &md->flags)) dm_start_queue(md->queue); unlock_fs(md); @@ -3067,7 +3069,7 @@ static int __dm_resume(struct mapped_device *md, struct dm_table *map) * so that mapping of targets can work correctly. * Request-based dm is queueing the deferred I/Os in its request_queue. */ - if (dm_request_based(md)) + if (test_and_clear_bit(DMF_QUEUE_STOPPED, &md->flags)) dm_start_queue(md->queue); unlock_fs(md); |