From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753983Ab2GDPGM (ORCPT ); Wed, 4 Jul 2012 11:06:12 -0400 Received: from mga09.intel.com ([134.134.136.24]:19966 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752849Ab2GDPGJ (ORCPT ); Wed, 4 Jul 2012 11:06:09 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.67,351,1309762800"; d="scan'208";a="166895797" From: "Liu, Chuansheng" To: Peter Zijlstra CC: "'linux-kernel@vger.kernel.org' (linux-kernel@vger.kernel.org)" , "kay@vrfy.org" , "gregkh@linuxfoundation.org" , "mingo@elte.hu" Subject: RE: [PATCH] printk: fixing the deadlock when calling printk in nmi handle Thread-Topic: [PATCH] printk: fixing the deadlock when calling printk in nmi handle Thread-Index: AQHNWfRptMUUmgrTR0OSqLbmXZzgzpcYrxwAgACI/UA= Date: Wed, 4 Jul 2012 15:06:06 +0000 Message-ID: <27240C0AC20F114CBF8149A2696CBE4A10CADD@SHSMSX101.ccr.corp.intel.com> References: <27240C0AC20F114CBF8149A2696CBE4A10C7F6@SHSMSX101.ccr.corp.intel.com> <1341408169.2507.111.camel@laptop> <27240C0AC20F114CBF8149A2696CBE4A10C84B@SHSMSX101.ccr.corp.intel.com> <1341409177.2507.117.camel@laptop> <27240C0AC20F114CBF8149A2696CBE4A10CA93@SHSMSX101.ccr.corp.intel.com> <1341413431.2507.124.camel@laptop> <1341413521.2507.125.camel@laptop> In-Reply-To: <1341413521.2507.125.camel@laptop> Accept-Language: zh-CN, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.239.127.40] Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by nfs id q64F6Gr0023593 > -----Original Message----- > From: Peter Zijlstra [mailto:peterz@infradead.org] > Sent: Wednesday, July 04, 2012 10:52 PM > To: Liu, Chuansheng > Cc: 'linux-kernel@vger.kernel.org' (linux-kernel@vger.kernel.org); kay@vrfy.org; > gregkh@linuxfoundation.org; mingo@elte.hu > Subject: RE: [PATCH] printk: fixing the deadlock when calling printk in nmi > handle > > On Wed, 2012-07-04 at 16:50 +0200, Peter Zijlstra wrote: > > On Wed, 2012-07-04 at 14:46 +0000, Liu, Chuansheng wrote: > > > > > I took many time to dig out this issue. > > > > > > > > Well, it was a known issue.. > > > Still feel unfair :) > > > If this is a known issue that calling printk is not safe in nmi > > > handler, Why not defense it like this patch before real solution coming out? > > > > Why replace one broken thing with another broken thing? > > Also, I much prefer obviously broken over subtly broken. Supporting your opinion totally, but from production view, it is not a good thing that system crash, I prefer to lose one log instead:) {.n++%ݶw{.n+{G{ayʇڙ,jfhz_(階ݢj"mG?&~iOzv^m ?I