From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935216Ab3GWWim (ORCPT ); Tue, 23 Jul 2013 18:38:42 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:41784 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934762Ab3GWW1p (ORCPT ); Tue, 23 Jul 2013 18:27:45 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, ybu , Peter Zijlstra , Thomas Gleixner Subject: [ 072/103] printk: Fix rq->lock vs logbuf_lock unlock lock inversion Date: Tue, 23 Jul 2013 15:26:23 -0700 Message-Id: <20130723220427.612031552@linuxfoundation.org> X-Mailer: git-send-email 1.8.3.rc0.20.gb99dd2e In-Reply-To: <20130723220418.532514378@linuxfoundation.org> References: <20130723220418.532514378@linuxfoundation.org> User-Agent: quilt/0.60-5.1.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: "Bu, Yitian" commit dbda92d16f8655044e082930e4e9d244b87fde77 upstream. commit 07354eb1a74d1 ("locking printk: Annotate logbuf_lock as raw") reintroduced a lock inversion problem which was fixed in commit 0b5e1c5255 ("printk: Release console_sem after logbuf_lock"). This happened probably when fixing up patch rejects. Restore the ordering and unlock logbuf_lock before releasing console_sem. Signed-off-by: ybu Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/E807E903FE6CBE4D95E420FBFCC273B827413C@nasanexd01h.na.qualcomm.com Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman --- kernel/printk.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/kernel/printk.c +++ b/kernel/printk.c @@ -1369,9 +1369,9 @@ static int console_trylock_for_printk(un } } logbuf_cpu = UINT_MAX; + raw_spin_unlock(&logbuf_lock); if (wake) up(&console_sem); - raw_spin_unlock(&logbuf_lock); return retval; }