From: Ming Lei
mainline inclusion
from mainline-v5.15-rc3
commit a647a524a46736786c95cdb553a070322ca096e3
category: bugfix
issue: #I4NRS5
CVE: NA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
Signed-off-by: Yu Changchun
---------------------------
rq_qos framework is only applied on request based driver, so:
1) rq_qos_done_bio() needn't to be called for bio based driver
2) rq_qos_done_bio() needn't to be called for bio which isn't tracked,
such as bios ended from error handling code.
Especially in bio_endio():
1) request queue is referred via bio->bi_bdev->bd_disk->queue, which
may be gone since request queue refcount may not be held in above two
cases
2) q->rq_qos may be freed in blk_cleanup_queue() when calling into
__rq_qos_done_bio()
Fix the potential kernel panic by not calling rq_qos_ops->done_bio if
the bio isn't tracked. This way is safe because both ioc_rqos_done_bio()
and blkcg_iolatency_done_bio() are nop if the bio isn't tracked.
Reported-by: Yu Kuai
Cc: tj@kernel.org
Signed-off-by: Ming Lei
Reviewed-by: Christoph Hellwig
Acked-by: Tejun Heo
Link: https://lore.kernel.org/r/20210924110704.1541818-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe
Conflict: block/bio.c
Signed-off-by: Yu Kuai
Reviewed-by: Jason Yan
Signed-off-by: Chen Jun
Signed-off-by: Zheng Zengkai
Signed-off-by: Yu Changchun
---
block/bio.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/block/bio.c b/block/bio.c
index 0703a208ca24..b2e0f0c94c5f 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -1433,7 +1433,7 @@ void bio_endio(struct bio *bio)
if (!bio_integrity_endio(bio))
return;
- if (bio->bi_disk)
+ if (bio->bi_disk && bio_flagged(bio, BIO_TRACKED))
rq_qos_done_bio(bio->bi_disk->queue, bio);
/*
--
2.25.1
