From: NeilBrown Date: Thu, 5 Oct 2017 05:23:16 +0000 (+1100) Subject: md: fix deadlock error in recent patch. X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=d47c8ad261f787af22a220ffcc2d07afba809223;p=linux.git md: fix deadlock error in recent patch. 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()") Cc: stable@vger.kernel.org Reported-by: Xiao Ni Signed-off-by: NeilBrown Signed-off-by: Shaohua Li --- diff --git a/drivers/md/md.c b/drivers/md/md.c index 0ff1bbf6c90e5..8b2eb0f4122fb 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;