From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935524AbcLMUF1 (ORCPT ); Tue, 13 Dec 2016 15:05:27 -0500 Received: from mx2.suse.de ([195.135.220.15]:54201 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933647AbcLMTxL (ORCPT ); Tue, 13 Dec 2016 14:53:11 -0500 X-Amavis-Alert: BAD HEADER SECTION, Duplicate header field: "References" From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Vitaly Kuznetsov , HATAYAMA Daisuke , Masami Hiramatsu , Jiri Kosina , Baoquan He , Prarit Bhargava , Xie XiuQi , Seth Jennings , "K. Y. Srinivasan" , Jan Kara , Petr Mladek , Yasuaki Ishimatsu , Andrew Morton , Linus Torvalds , Jiri Slaby Subject: [PATCH 3.12 06/38] kernel/panic.c: turn off locks debug before releasing console lock Date: Tue, 13 Dec 2016 20:52:32 +0100 Message-Id: X-Mailer: git-send-email 2.11.0 In-Reply-To: <15034b96ec06ee859b67c6cd4e3be569a4ef286b.1481658746.git.jslaby@suse.cz> References: <15034b96ec06ee859b67c6cd4e3be569a4ef286b.1481658746.git.jslaby@suse.cz> In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Vitaly Kuznetsov 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit 7625b3a0007decf2b135cb47ca67abc78a7b1bc1 upstream. Commit 08d78658f393 ("panic: release stale console lock to always get the logbuf printed out") introduced an unwanted bad unlock balance report when panic() is called directly and not from OOPS (e.g. from out_of_memory()). The difference is that in case of OOPS we disable locks debug in oops_enter() and on direct panic call nobody does that. Fixes: 08d78658f393 ("panic: release stale console lock to always get the logbuf printed out") Reported-by: kernel test robot Signed-off-by: Vitaly Kuznetsov Cc: HATAYAMA Daisuke Cc: Masami Hiramatsu Cc: Jiri Kosina Cc: Baoquan He Cc: Prarit Bhargava Cc: Xie XiuQi Cc: Seth Jennings Cc: "K. Y. Srinivasan" Cc: Jan Kara Cc: Petr Mladek Cc: Yasuaki Ishimatsu Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Jiri Slaby --- kernel/panic.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/kernel/panic.c b/kernel/panic.c index de5924c75b1b..639255d5e5e1 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -138,8 +138,11 @@ void panic(const char *fmt, ...) * We may have ended up stopping the CPU holding the lock (in * smp_send_stop()) while still having some valuable data in the console * buffer. Try to acquire the lock then release it regardless of the - * result. The release will also print the buffers out. + * result. The release will also print the buffers out. Locks debug + * should be disabled to avoid reporting bad unlock balance when + * panic() is not being callled from OOPS. */ + debug_locks_off(); console_flush_on_panic(); if (!panic_blink) -- 2.11.0