commit 93dec51e716db88f32d770dc9ab268964fff320b
author Yu Kuai <yukuai3@huawei.com> Wed Sep 03 09:41:40 2025 +0800
committer Yu Kuai <yukuai3@huawei.com> Fri Sep 05 00:30:04 2025 +0800
tree 3f896359a6d92ad2c194115ab37a1a7c0f5cb808
parent 95a7c5000956f939b86d8b00b8e6b8345f4a9b65

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 <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@huaweicloud.com
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Li Nan <linan122@huawei.com>