md/raid1: fix writebehind bio clone
authorShaohua Li <shli@fb.com>
Mon, 17 Jul 2017 21:33:48 +0000 (14:33 -0700)
committerShaohua Li <shli@fb.com>
Fri, 21 Jul 2017 19:47:20 +0000 (12:47 -0700)
commit16d56e2fcc1fc15b981369653c3b41d7ff0b443d
treeead4908160acc2c9192c78898f1f5ec8062d231d
parentbe453e7761d0e72d8a1b2fcfde6d1a7e53881190
md/raid1: fix writebehind bio clone

After bio is submitted, we should not clone it as its bi_iter might be
invalid by driver. This is the case of behind_master_bio. In certain
situration, we could dispatch behind_master_bio immediately for the
first disk and then clone it for other disks.

https://bugzilla.kernel.org/show_bug.cgi?id=196383

Reported-and-tested-by: Markus <m4rkusxxl@web.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Fix: 841c1316c7da(md: raid1: improve write behind)
Cc: stable@vger.kernel.org (4.12+)
Signed-off-by: Shaohua Li <shli@fb.com>
drivers/md/raid1.c