From 459aad50a56bfca28cc41408448d08abdd7e17ae Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Thu, 5 Oct 2017 16:23:16 +1100 Subject: [PATCH] md: fix deadlock error in recent patch. 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 Signed-off-by: NeilBrown Signed-off-by: Shaohua Li Signed-off-by: Greg Kroah-Hartman --- drivers/md/md.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index 0ff1bbf6c90e..8b2eb0f4122f 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -8039,7 +8039,8 @@ bool md_write_start(struct mddev *mddev, struct bio *bi) 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; -- 2.20.1