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 /block/blk-cgroup.c | |
| 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 'block/blk-cgroup.c')
| -rw-r--r-- | block/blk-cgroup.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 45a395862fbc..c795fa3a30e1 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -1545,6 +1545,7 @@ int blkcg_activate_policy(struct gendisk *disk, const struct blkcg_policy *pol) struct request_queue *q = disk->queue; struct blkg_policy_data *pd_prealloc = NULL; struct blkcg_gq *blkg, *pinned_blkg = NULL; + unsigned int memflags; int ret; if (blkcg_policy_enabled(q, pol)) @@ -1559,7 +1560,7 @@ int blkcg_activate_policy(struct gendisk *disk, const struct blkcg_policy *pol) return -EINVAL; if (queue_is_mq(q)) - blk_mq_freeze_queue(q); + memflags = blk_mq_freeze_queue(q); retry: spin_lock_irq(&q->queue_lock); @@ -1623,7 +1624,7 @@ retry: spin_unlock_irq(&q->queue_lock); out: if (queue_is_mq(q)) - blk_mq_unfreeze_queue(q); + blk_mq_unfreeze_queue(q, memflags); if (pinned_blkg) blkg_put(pinned_blkg); if (pd_prealloc) @@ -1667,12 +1668,13 @@ void blkcg_deactivate_policy(struct gendisk *disk, { struct request_queue *q = disk->queue; struct blkcg_gq *blkg; + unsigned int memflags; if (!blkcg_policy_enabled(q, pol)) return; if (queue_is_mq(q)) - blk_mq_freeze_queue(q); + memflags = blk_mq_freeze_queue(q); mutex_lock(&q->blkcg_mutex); spin_lock_irq(&q->queue_lock); @@ -1696,7 +1698,7 @@ void blkcg_deactivate_policy(struct gendisk *disk, mutex_unlock(&q->blkcg_mutex); if (queue_is_mq(q)) - blk_mq_unfreeze_queue(q); + blk_mq_unfreeze_queue(q, memflags); } EXPORT_SYMBOL_GPL(blkcg_deactivate_policy); |