mm: __set_page_dirty uses spin_lock_irqsave instead of spin_lock_irq
To use spin_{un}lock_irq is dangerous if caller disabled interrupt.
During aio buffer migration, we have a possibility to see the following
call stack.
aio_migratepage [disable interrupt]
migrate_page_copy
clear_page_dirty_for_io
set_page_dirty
__set_page_dirty_buffers
__set_page_dirty
spin_lock_irq
This mean, current aio migration is a deadlockable. spin_lock_irqsave
is a safer alternative and we should use it.
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reported-by: David Rientjes rientjes@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 file changed