6.12-stable review patch. If anyone has any objections, please let me know.
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From: Yu Kuai yukuai3@huawei.com
[ Upstream commit 93dec51e716db88f32d770dc9ab268964fff320b ]
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 ian@beware.dropbear.id.au Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220507 Link: https://lore.kernel.org/linux-raid/20250903014140.3690499-1-yukuai1@huaweicl... Signed-off-by: Yu Kuai yukuai3@huawei.com Reviewed-by: Li Nan linan122@huawei.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/md/raid1.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 772486d707181..faccf7344ef93 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -1224,7 +1224,7 @@ 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 */