On Mon, May 22, 2017 at 04:39:43PM +0900, Sergey Senozhatsky wrote:
Hello,
[ 1274.378287] ======================================================
[ 1274.378289] WARNING: possible circular locking dependency detected
[ 1274.378290] 4.12.0-rc1-next-20170522-dbg-00007-gc09b2ab28b74-dirty #1317 Not tainted
[ 1274.378291] ------------------------------------------------------
[ 1274.378293] kworker/u8:5/111 is trying to acquire lock:
[ 1274.378294] (&buf->lock){+.+...}, at: [<ffffffff812f2831>] tty_buffer_flush+0x34/0x88
[ 1274.378300]
but task is already holding lock:
[ 1274.378301] (&o_tty->termios_rwsem/1){++++..}, at: [<ffffffff812ee5c7>] isig+0x47/0xd2
[ 1274.378307]
which lock already depends on the new lock.
Any hint as to what you were doing when this happened?
Does this also show up in 4.11?