From: Christoph Hellwig Date: Mon, 24 Sep 2018 07:43:51 +0000 (+0200) Subject: block: add a missing BIOVEC_SEG_BOUNDARY check in bio_add_pc_page X-Git-Tag: v4.20-rc1~191^2~149 X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=0e253391a970300fe4ae69d0c1d1ab494eb07508;p=uclinux-h8%2Flinux.git block: add a missing BIOVEC_SEG_BOUNDARY check in bio_add_pc_page The actual recaculation of segments in __blk_recalc_rq_segments will do this check, so there is no point in forcing it if we know it won't succeed. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- diff --git a/block/bio.c b/block/bio.c index 81d90b839e05..c254e5aa331f 100644 --- a/block/bio.c +++ b/block/bio.c @@ -731,7 +731,9 @@ int bio_add_pc_page(struct request_queue *q, struct bio *bio, struct page } /* If we may be able to merge these biovecs, force a recount */ - if (bio->bi_vcnt > 1 && biovec_phys_mergeable(bvec-1, bvec)) + if (bio->bi_vcnt > 1 && + biovec_phys_mergeable(bvec - 1, bvec) && + BIOVEC_SEG_BOUNDARY(q, bvec - 1, bvec)) bio_clear_flag(bio, BIO_SEG_VALID); done: