path: root/block/blk-merge.c
diff options
authorLinus Torvalds <torvalds@linux-foundation.org>2019-01-27 10:58:20 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2019-01-27 10:58:20 -0800
commit419967d53fc74bb151cdc9a00d0df80a2cc37173 (patch)
tree68fefeb5682a501282775db074aa68c192f89252 /block/blk-merge.c
parent1fc7f56db7a7c467e46a5d2e2a009d2f337e0338 (diff)
parent947b7ac135b16aa60f9141ff72bd494eda0edb5e (diff)
Merge tag 'for-linus-20190127' of git://git.kernel.dk/linux-block
Pull block revert from Jens Axboe: "Silly error snuck into a patch from the last series, let's do a revert to avoid a potential use-after-free" * tag 'for-linus-20190127' of git://git.kernel.dk/linux-block: Revert "block: cover another queue enter recursion via BIO_QUEUE_ENTERED"
Diffstat (limited to 'block/blk-merge.c')
1 files changed, 10 insertions, 0 deletions
diff --git a/block/blk-merge.c b/block/blk-merge.c
index d79a22f111d1..71e9ac03f621 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -272,6 +272,16 @@ void blk_queue_split(struct request_queue *q, struct bio **bio)
/* there isn't chance to merge the splitted bio */
split->bi_opf |= REQ_NOMERGE;
+ /*
+ * Since we're recursing into make_request here, ensure
+ * that we mark this bio as already having entered the queue.
+ * If not, and the queue is going away, we can get stuck
+ * forever on waiting for the queue reference to drop. But
+ * that will never happen, as we're already holding a
+ * reference to it.
+ */
+ bio_set_flag(*bio, BIO_QUEUE_ENTERED);
bio_chain(split, *bio);
trace_block_split(q, split, (*bio)->bi_iter.bi_sector);