Hello Christoph Hellwig,
This is a semi-automatic email about new static checker warnings.
Commit 61952bb73486 ("block: remove the write_hint field from struct
request") from Nov 12, 2024, leads to the following Smatch complaint:
block/blk-merge.c:1005 blk_rq_merge_ok() warn: variable dereferenced before check 'rq->bio' (see line 994)
block/blk-merge.c
993 /* don't merge across cgroup boundaries */
994 if (!blk_cgroup_mergeable(rq, bio))
^^
This dereferences rq->bio->
995 return false;
996
997 /* only merge integrity protected bio into ditto rq */
998 if (blk_integrity_merge_bio(rq->q, rq, bio) == false)
999 return false;
1000
1001 /* Only merge if the crypt contexts are compatible */
1002 if (!bio_crypt_rq_ctx_compatible(rq, bio))
1003 return false;
1004
1005 if (rq->bio) {
^^^^^^^
So this check shouldn't be required.
1006 /* Don't merge requests with different write hints. */
1007 if (rq->bio->bi_write_hint != bio->bi_write_hint)
regards,
dan carpenter
