This is a note to let you know that I've just added the patch titled
md: fix deadlock error in recent patch.
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
md-fix-deadlock-error-in-recent-patch.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From d47c8ad261f787af22a220ffcc2d07afba809223 Mon Sep 17 00:00:00 2001
From: NeilBrown <neilb@xxxxxxxx>
Date: Thu, 5 Oct 2017 16:23:16 +1100
Subject: md: fix deadlock error in recent patch.
From: NeilBrown <neilb@xxxxxxxx>
commit d47c8ad261f787af22a220ffcc2d07afba809223 upstream.
A recent patch aimed to cause md_write_start() to fail (rather than
block) when the mddev was suspending, so as to avoid deadlocks.
Unfortunately the test in wait_event() was wrong, and it didn't change
behaviour at all.
We wait_event() must wait until the metadata is written OR the array is
suspending.
Fixes: cc27b0c78c79 ("md: fix deadlock between mddev_suspend() and md_write_start()")
Reported-by: Xiao Ni <xni@xxxxxxxxxx>
Signed-off-by: NeilBrown <neilb@xxxxxxxx>
Signed-off-by: Shaohua Li <shli@xxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/md/md.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -8039,7 +8039,8 @@ bool md_write_start(struct mddev *mddev,
if (did_change)
sysfs_notify_dirent_safe(mddev->sysfs_state);
wait_event(mddev->sb_wait,
- !test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags) && !mddev->suspended);
+ !test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags) ||
+ mddev->suspended);
if (test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags)) {
percpu_ref_put(&mddev->writes_pending);
return false;
Patches currently in stable-queue which might be from neilb@xxxxxxxx are
queue-4.14/md-fix-deadlock-error-in-recent-patch.patch
queue-4.14/autofs-don-t-fail-mount-for-transient-error.patch
queue-4.14/md-bitmap-revert-a-patch.patch
queue-4.14/nfs-revalidate-.-etc-correctly-on-open.patch