From: Yu Kuai Date: Wed, 3 Sep 2025 01:41:40 +0000 (+0800) Subject: md/raid1: fix data lost for writemostly rdev X-Git-Tag: v6.17-rc5~17^2^2~1 X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=93dec51e716db88f32d770dc9ab268964fff320b;p=users%2Fgriffoul%2Flinux.git md/raid1: fix data lost for writemostly rdev If writemostly is enabled, alloc_behind_master_bio() will allocate a new bio for rdev, with bi_opf set to 0. Later, raid1_write_request() will clone from this bio, hence bi_opf is still 0 for the cloned bio. Submit this cloned bio will end up to be read, causing write data lost. Fix this problem by inheriting bi_opf from original bio for behind_mast_bio. Fixes: e879a0d9cb08 ("md/raid1,raid10: don't ignore IO flags") Reported-and-tested-by: Ian Dall Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220507 Link: https://lore.kernel.org/linux-raid/20250903014140.3690499-1-yukuai1@huaweicloud.com Signed-off-by: Yu Kuai Reviewed-by: Li Nan --- diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 408c26398321..bf44878ec640 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -1225,7 +1225,7 @@ static void alloc_behind_master_bio(struct r1bio *r1_bio, int i = 0; struct bio *behind_bio = NULL; - behind_bio = bio_alloc_bioset(NULL, vcnt, 0, GFP_NOIO, + behind_bio = bio_alloc_bioset(NULL, vcnt, bio->bi_opf, GFP_NOIO, &r1_bio->mddev->bio_set); /* discard op, we don't support writezero/writesame yet */