From 12c2bdb232168511c8dd54d6626549391a228918 Mon Sep 17 00:00:00 2001 From: Derek Basehore Date: Tue, 18 Dec 2012 12:27:20 -0800 Subject: [PATCH] block: prevent race/cleanup Remove a race condition which causes a warning in disk_clear_events. This is a race between disk_clear_events() and disk_flush_events(). ev->clearing will be altered by disk_flush_events() even though we are blocking event checking through disk_flush_events(). If this happens after ev->clearing was cleared for disk_clear_events(), this can cause the WARN_ON_ONCE() in that function to be triggered. This change also has disk_clear_events() not go through a workqueue. Since we have to wait for the work to complete, we should just call the function directly. Also, since this work cannot be put on a freezable workqueue, it will have to contend with increased demand, so calling the function directly avoids this. [akpm@linux-foundation.org: fix spello in comment] Signed-off-by: Derek Basehore Cc: Mandeep Singh Baines Cc: Jens Axboe Signed-off-by: Andrew Morton Signed-off-by: Jens Axboe --- Reading git-format-patch failed