mirrors/linux
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2025-12-27 10:01:39 -05:00
Code Issues Packages Projects Releases Wiki Activity

zloop: use READ_ONCE() to read lo->lo_state in queue_rq path

Browse Source 
In the queue_rq path, zlo->state is accessed without locking, and direct
access may read stale data. This patch uses READ_ONCE() to read
zlo->state and data_race() to silence code checkers, and changes all
assignments to use WRITE_ONCE().

Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Yongpeng Yang <yangyongpeng@xiaomi.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Yongpeng Yang
2025-12-15 23:21:06 +08:00
committed by Jens Axboe
parent 54891a96b7
commit 4b2b03151e
1 changed files with 4 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files

8
drivers/block/zloop.c
View File

@@ -697,7 +697,7 @@ static blk_status_t zloop_queue_rq(struct blk_mq_hw_ctx *hctx,
struct zloop_cmd *cmd = blk_mq_rq_to_pdu(rq);
struct zloop_device *zlo = rq->q->queuedata;
if (zlo->state == Zlo_deleting)
if (data_race(READ_ONCE(zlo->state)) == Zlo_deleting)
return BLK_STS_IOERR;
/*
@@ -1002,7 +1002,7 @@ static int zloop_ctl_add(struct zloop_options *opts)
ret = -ENOMEM;
goto out;
}
zlo->state = Zlo_creating;
WRITE_ONCE(zlo->state, Zlo_creating);
ret = mutex_lock_killable(&zloop_ctl_mutex);
if (ret)
@@ -1113,7 +1113,7 @@ static int zloop_ctl_add(struct zloop_options *opts)
}
mutex_lock(&zloop_ctl_mutex);
zlo->state = Zlo_live;
WRITE_ONCE(zlo->state, Zlo_live);
mutex_unlock(&zloop_ctl_mutex);
pr_info("zloop: device %d, %u zones of %llu MiB, %u B block size\n",
@@ -1177,7 +1177,7 @@ static int zloop_ctl_remove(struct zloop_options *opts)
ret = -EINVAL;
} else {
idr_remove(&zloop_index_idr, zlo->id);
zlo->state = Zlo_deleting;
WRITE_ONCE(zlo->state, Zlo_deleting);
}
mutex_unlock(&zloop_ctl_mutex);