From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933425AbdC3LR1 (ORCPT ); Thu, 30 Mar 2017 07:17:27 -0400 Received: from mail.skyhub.de ([5.9.137.197]:52450 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932944AbdC3LRZ (ORCPT ); Thu, 30 Mar 2017 07:17:25 -0400 Date: Thu, 30 Mar 2017 13:17:14 +0200 From: Borislav Petkov To: x86-ml Cc: lkml Subject: [PATCH] x86/mce/AMD: Give a name to MCA bank 3 when accessed with legacy MSRs Message-ID: <20170330111713.cnkbloffyouxg52e@pd.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Yazen Ghannam MCA bank 3 is reserved on systems pre-Fam17h, so it didn't have a name. However, MCA bank 3 is defined on Fam17h systems and can be accessed using legacy MSRs. Without a name we get a stack trace on Fam17h systems when trying to register sysfs files for bank 3 on kernels that don't recognize Scalable MCA. Call MCA bank 3 "decode_unit" since this is what it represents on Fam17h. This will allow kernels without SMCA support to see this bank on Fam17h+ and prevent the stack trace. This will not affect older systems since this bank is reserved on them, i.e. it'll be ignored. Tested on AMD Fam15h and Fam17h systems. WARNING: CPU: 26 PID: 1 at lib/kobject.c:210 kobject_add_internal kobject: (ffff88085bb256c0): attempted to be registered with empty name! ... Call Trace: dump_stack warn_slowpath_common warn_slowpath_fmt ? kobject_add_internal ? kfree_const kobject_add_internal ? kfree_const kobject_add kobject_create_and_add threshold_create_device ? mcheck_vendor_init_severity threshold_init_device do_one_initcall kernel_init_freeable ? rest_init kernel_init ret_from_fork ? rest_init Signed-off-by: Yazen Ghannam Cc: # 3.10.. Cc: linux-edac Cc: x86-ml Link: http://lkml.kernel.org/r/1490102285-3659-1-git-send-email-Yazen.Ghannam@amd.com Signed-off-by: Borislav Petkov --- To tip/ras/urgent pls. arch/x86/kernel/cpu/mcheck/mce_amd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/cpu/mcheck/mce_amd.c b/arch/x86/kernel/cpu/mcheck/mce_amd.c index 524cc5780a77..6e4a047e4b68 100644 --- a/arch/x86/kernel/cpu/mcheck/mce_amd.c +++ b/arch/x86/kernel/cpu/mcheck/mce_amd.c @@ -60,7 +60,7 @@ static const char * const th_names[] = { "load_store", "insn_fetch", "combined_unit", - "", + "decode_unit", "northbridge", "execution_unit", }; -- 2.11.0 -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.