Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761572Ab2FEJ5m (ORCPT ); Tue, 5 Jun 2012 05:57:42 -0400 Received: from mga01.intel.com ([192.55.52.88]:23834 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755166Ab2FEJ5l (ORCPT ); Tue, 5 Jun 2012 05:57:41 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.71,315,1320652800"; d="scan'208";a="174951565" Message-ID: <4FCDD78A.3070106@intel.com> Date: Tue, 05 Jun 2012 17:55:22 +0800 From: ShuoX Liu Reply-To: shuox.liu@intel.com User-Agent: Mozilla/5.0 (X11; Linux i686; rv:12.0) Gecko/20120428 Thunderbird/12.0.1 MIME-Version: 1.0 To: "linux-kernel@vger.kernel.org" CC: Borislav Petkov , Yanmin Zhang , "Luck, Tony" , Andrew Morton , "andi@firstfloor.org" , Ingo Molnar Subject: [PATCH v5 2/2] x86 mce: use new printk recursion disabling interface References: <20120524061145.GA18284@liondog.tnic> <20120524155611.b7aeff4d.akpm@linux-foundation.org> <1337905811.14538.206.camel@ymzhang.sh.intel.com> <4FBF3295.7090608@intel.com> <3908561D78D1C84285E8C5FCA982C28F192F4D39@ORSMSX104.amr.corp.intel.com> <1338165058.14538.209.camel@ymzhang.sh.intel.com> <4FC2E8CF.2040109@intel.com> <4FC2E944.6060903@intel.com> <20120604171202.GA8533@x1.osrc.amd.com> <1338856360.14538.220.camel@ymzhang.sh.intel.com> <20120605081448.GA7097@liondog.tnic> <4FCDD72A.9030701@intel.com> In-Reply-To: <4FCDD72A.9030701@intel.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1636 Lines: 47 From: ShuoX Liu On x86 machines, some times MCE happens just when kernel calls printk to output some log info to serial console, while usually MCE module in kernel is used to print out some hardware error information, such like bad cache or bad memory bank. That causes printk recursion and printk would omit MCE printk output. We hit it when running MTBF testing on Android ATOM mobiles. Here in mce_panic, we choose to disable printk recursion to make sure MCE logs printed out. Signed-off-by: Yanmin Zhang Signed-off-by: ShuoX Liu --- arch/x86/kernel/cpu/mcheck/mce.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-) diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c index 2afcbd2..906e838 100644 --- a/arch/x86/kernel/cpu/mcheck/mce.c +++ b/arch/x86/kernel/cpu/mcheck/mce.c @@ -306,6 +306,7 @@ static void mce_panic(char *msg, struct mce *final, char *exp) { int i, apei_err = 0; + printk_recursion_check_disable(); if (!fake_panic) { /* * Make sure only one CPU runs in machine check panic @@ -360,6 +361,7 @@ static void mce_panic(char *msg, struct mce *final, char *exp) panic(msg); } else pr_emerg(HW_ERR "Fake kernel panic: %s\n", msg); + printk_recursion_check_enable(); } /* Support code for software error injection */ -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/