diff options
| author | Li Nan <linan122@huawei.com> | 2025-08-26 16:48:54 +0800 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2025-08-28 19:21:07 -0600 |
| commit | 4c7ef92f6d4d08a27d676e4c348f4e2922cab3ed (patch) | |
| tree | 5fe2e49fc22a8510c42e365a9c33f3146d94f7e3 | |
| parent | d4399e6eb27a803b73d17fe984448a823b4d3a30 (diff) | |
blk-mq: check kobject state_in_sysfs before deleting in blk_mq_unregister_hctx
In __blk_mq_update_nr_hw_queues() the return value of
blk_mq_sysfs_register_hctxs() is not checked. If sysfs creation for hctx
fails, later changing the number of hw_queues or removing disk will
trigger the following warning:
kernfs: can not remove 'nr_tags', no directory
WARNING: CPU: 2 PID: 637 at fs/kernfs/dir.c:1707 kernfs_remove_by_name_ns+0x13f/0x160
Call Trace:
remove_files.isra.1+0x38/0xb0
sysfs_remove_group+0x4d/0x100
sysfs_remove_groups+0x31/0x60
__kobject_del+0x23/0xf0
kobject_del+0x17/0x40
blk_mq_unregister_hctx+0x5d/0x80
blk_mq_sysfs_unregister_hctxs+0x94/0xd0
blk_mq_update_nr_hw_queues+0x124/0x760
nullb_update_nr_hw_queues+0x71/0xf0 [null_blk]
nullb_device_submit_queues_store+0x92/0x120 [null_blk]
kobjct_del() was called unconditionally even if sysfs creation failed.
Fix it by checkig the kobject creation statusbefore deleting it.
Fixes: 477e19dedc9d ("blk-mq: adjust debugfs and sysfs register when updating nr_hw_queues")
Signed-off-by: Li Nan <linan122@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20250826084854.1030545-1-linan666@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | block/blk-mq-sysfs.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/block/blk-mq-sysfs.c b/block/blk-mq-sysfs.c index 24656980f443..5c399ac562ea 100644 --- a/block/blk-mq-sysfs.c +++ b/block/blk-mq-sysfs.c @@ -150,9 +150,11 @@ static void blk_mq_unregister_hctx(struct blk_mq_hw_ctx *hctx) return; hctx_for_each_ctx(hctx, ctx, i) - kobject_del(&ctx->kobj); + if (ctx->kobj.state_in_sysfs) + kobject_del(&ctx->kobj); - kobject_del(&hctx->kobj); + if (hctx->kobj.state_in_sysfs) + kobject_del(&hctx->kobj); } static int blk_mq_register_hctx(struct blk_mq_hw_ctx *hctx) |