md: avoid possible spinning md thread at shutdown.
If an md array with externally managed metadata (e.g. DDF or IMSM)
is in use, then we should not set safemode==2 at shutdown because:
1/ this is ineffective: user-space need to be involved in any 'safemode' handling,
2/ The safemode management code doesn't cope with safemode==2 on external metadata
and md_check_recover enters an infinite loop.
Even at shutdown, an infinite-looping process can be problematic, so this
could cause shutdown to hang.
Cc: stable@vger.kernel.org (any kernel)
Signed-off-by: NeilBrown <neilb@suse.de>
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 8fda38d..237b7e0 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -8516,7 +8516,8 @@
if (mddev_trylock(mddev)) {
if (mddev->pers)
__md_stop_writes(mddev);
- mddev->safemode = 2;
+ if (mddev->persistent)
+ mddev->safemode = 2;
mddev_unlock(mddev);
}
need_delay = 1;