From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752364Ab2GDNaR (ORCPT ); Wed, 4 Jul 2012 09:30:17 -0400 Received: from mga02.intel.com ([134.134.136.20]:4133 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750797Ab2GDNaO (ORCPT ); Wed, 4 Jul 2012 09:30:14 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.67,352,1309762800"; d="scan'208";a="161353424" 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: AQHNWegxNurOYIWfgUuAR26n58tdbpcZHgAw Date: Wed, 4 Jul 2012 13:30:10 +0000 Message-ID: <27240C0AC20F114CBF8149A2696CBE4A10C84B@SHSMSX101.ccr.corp.intel.com> References: <27240C0AC20F114CBF8149A2696CBE4A10C7F6@SHSMSX101.ccr.corp.intel.com> <1341408169.2507.111.camel@laptop> In-Reply-To: <1341408169.2507.111.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 q64DULko022998 > Yuck.. and no. This makes sane things like early 8250 serial console less > reliable. Peter, could you share more? I took many time to dig out this issue. Anyway, in nmi handler, calling printk is dangerous. This patch is for this case. {.n++%ݶw{.n+{G{ayʇڙ,jfhz_(階ݢj"mG?&~iOzv^m ?I