From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kyoungil Kim Subject: RE: [PATCH] serial: samsung: protect NULL dereference of clock name Date: Wed, 30 May 2012 18:28:03 +0900 Message-ID: <001701cd3e46$8372bce0$8a5836a0$%kim@samsung.com> References: <001401cd3e3e$644fd3a0$2cef7ae0$%kim@samsung.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Return-path: Received: from mailout2.samsung.com ([203.254.224.25]:36675 "EHLO mailout2.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932381Ab2E3J2G (ORCPT ); Wed, 30 May 2012 05:28:06 -0400 In-reply-to: Content-language: ko Sender: linux-serial-owner@vger.kernel.org List-Id: linux-serial@vger.kernel.org To: 'Shubhrajyoti Datta' Cc: linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-serial@vger.kernel.org, 'Kukjin Kim' , 'Alan Cox' , 'KeyYoung Park' , 'Huisung Kang' Shubhrajyoti Datta wrote: > Hi Kim, > On Wed, May 30, 2012 at 1:59 PM, Kyoungil Kim wrote: > > From: KeyYoung Park > > > > When priting the serial clock source, if clock source name is null, > > kernel reference NULL point. > > > Could you help me understand why is that NULL ? Or the crash that you saw. When you want to see the serial clock source name like using cat command before you open the tty, You can see the kernel crash. I know this is not normal scenario. This patch just prevents the kernel panic.