diff options
| author | Christoph Hellwig <hch@lst.de> | 2025-01-31 13:03:47 +0100 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2025-01-31 07:20:08 -0700 |
| commit | 1e1a9cecfab3f22ebef0a976f849c87be8d03c1c (patch) | |
| tree | 34fa7958ed94c56127aa0fc55347bb409574af3a /drivers/scsi | |
| parent | 14ef49657ff3b7156952b2eadcf2e5bafd735795 (diff) | |
block: force noio scope in blk_mq_freeze_queue
When block drivers or the core block code perform allocations with a
frozen queue, this could try to recurse into the block device to
reclaim memory and deadlock. Thus all allocations done by a process
that froze a queue need to be done without __GFP_IO and __GFP_FS.
Instead of tying to track all of them down, force a noio scope as
part of freezing the queue.
Note that nvme is a bit of a mess here due to the non-owner freezes,
and they will be addressed separately.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250131120352.1315351-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers/scsi')
| -rw-r--r-- | drivers/scsi/scsi_lib.c | 5 | ||||
| -rw-r--r-- | drivers/scsi/scsi_scan.c | 5 |
2 files changed, 6 insertions, 4 deletions
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 4411426a7894..b86e259516a7 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -2723,6 +2723,7 @@ int scsi_device_quiesce(struct scsi_device *sdev) { struct request_queue *q = sdev->request_queue; + unsigned int memflags; int err; /* @@ -2737,7 +2738,7 @@ scsi_device_quiesce(struct scsi_device *sdev) blk_set_pm_only(q); - blk_mq_freeze_queue(q); + memflags = blk_mq_freeze_queue(q); /* * Ensure that the effect of blk_set_pm_only() will be visible * for percpu_ref_tryget() callers that occur after the queue @@ -2745,7 +2746,7 @@ scsi_device_quiesce(struct scsi_device *sdev) * was called. See also https://lwn.net/Articles/573497/. */ synchronize_rcu(); - blk_mq_unfreeze_queue(q); + blk_mq_unfreeze_queue(q, memflags); mutex_lock(&sdev->state_mutex); err = scsi_device_set_state(sdev, SDEV_QUIESCE); diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c index 042329b74c6e..312d78213954 100644 --- a/drivers/scsi/scsi_scan.c +++ b/drivers/scsi/scsi_scan.c @@ -220,6 +220,7 @@ static int scsi_realloc_sdev_budget_map(struct scsi_device *sdev, int new_shift = sbitmap_calculate_shift(depth); bool need_alloc = !sdev->budget_map.map; bool need_free = false; + unsigned int memflags; int ret; struct sbitmap sb_backup; @@ -240,7 +241,7 @@ static int scsi_realloc_sdev_budget_map(struct scsi_device *sdev, * and here disk isn't added yet, so freezing is pretty fast */ if (need_free) { - blk_mq_freeze_queue(sdev->request_queue); + memflags = blk_mq_freeze_queue(sdev->request_queue); sb_backup = sdev->budget_map; } ret = sbitmap_init_node(&sdev->budget_map, @@ -256,7 +257,7 @@ static int scsi_realloc_sdev_budget_map(struct scsi_device *sdev, else sbitmap_free(&sb_backup); ret = 0; - blk_mq_unfreeze_queue(sdev->request_queue); + blk_mq_unfreeze_queue(sdev->request_queue, memflags); } return ret; } |