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| 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-sysfs.c | |
| parent | 14ef49657ff3b7156952b2eadcf2e5bafd735795 (diff) | |
| download | linux-1e1a9cecfab3f22ebef0a976f849c87be8d03c1c.tar.gz linux-1e1a9cecfab3f22ebef0a976f849c87be8d03c1c.tar.bz2 linux-1e1a9cecfab3f22ebef0a976f849c87be8d03c1c.zip | |
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-sysfs.c')
| -rw-r--r-- | block/blk-sysfs.c | 8 |
1 files changed, 3 insertions, 5 deletions
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 7b970e6765e7..6f548a4376aa 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -681,7 +681,7 @@ queue_attr_store(struct kobject *kobj, struct attribute *attr, struct queue_sysfs_entry *entry = to_queue(attr); struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj); struct request_queue *q = disk->queue; - unsigned int noio_flag; + unsigned int memflags; ssize_t res; if (!entry->store_limit && !entry->store) @@ -711,11 +711,9 @@ queue_attr_store(struct kobject *kobj, struct attribute *attr, } mutex_lock(&q->sysfs_lock); - blk_mq_freeze_queue(q); - noio_flag = memalloc_noio_save(); + memflags = blk_mq_freeze_queue(q); res = entry->store(disk, page, length); - memalloc_noio_restore(noio_flag); - blk_mq_unfreeze_queue(q); + blk_mq_unfreeze_queue(q, memflags); mutex_unlock(&q->sysfs_lock); return res; } |