From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 41vBDp4BF9zDqp5 for ; Mon, 20 Aug 2018 21:20:26 +1000 (AEST) Received: from ozlabs.org (bilbo.ozlabs.org [IPv6:2401:3900:2:1::2]) by bilbo.ozlabs.org (Postfix) with ESMTP id 41vBDp2FlDz8t88 for ; Mon, 20 Aug 2018 21:20:26 +1000 (AEST) Received: from mail-pf1-x442.google.com (mail-pf1-x442.google.com [IPv6:2607:f8b0:4864:20::442]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 41vBDm0vqcz9s89 for ; Mon, 20 Aug 2018 21:20:23 +1000 (AEST) Received: by mail-pf1-x442.google.com with SMTP id k19-v6so6614659pfi.1 for ; Mon, 20 Aug 2018 04:20:23 -0700 (PDT) Date: Mon, 20 Aug 2018 21:20:15 +1000 From: Nicholas Piggin To: Mahesh J Salgaonkar Cc: linuxppc-dev , "Aneesh Kumar K.V" , Michael Ellerman , Ananth Narayan , Laurent Dufour , "Aneesh Kumar K.V" , Michal Suchanek Subject: Re: [PATCH v8 4/5] powerpc/pseries: Dump the SLB contents on SLB MCE errors. Message-ID: <20180820212015.163c12ff@roar.ozlabs.ibm.com> In-Reply-To: <153469851207.21878.16970346624861719956.stgit@jupiter.in.ibm.com> References: <153469837203.21878.11524005112982522827.stgit@jupiter.in.ibm.com> <153469851207.21878.16970346624861719956.stgit@jupiter.in.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Sun, 19 Aug 2018 22:38:32 +0530 Mahesh J Salgaonkar wrote: > From: Mahesh Salgaonkar > > If we get a machine check exceptions due to SLB errors then dump the > current SLB contents which will be very much helpful in debugging the > root cause of SLB errors. Introduce an exclusive buffer per cpu to hold > faulty SLB entries. In real mode mce handler saves the old SLB contents > into this buffer accessible through paca and print it out later in virtual > mode. > > With this patch the console will log SLB contents like below on SLB MCE > errors: > > [ 507.297236] SLB contents of cpu 0x1 > [ 507.297237] Last SLB entry inserted at slot 16 > [ 507.297238] 00 c000000008000000 400ea1b217000500 > [ 507.297239] 1T ESID= c00000 VSID= ea1b217 LLP:100 > [ 507.297240] 01 d000000008000000 400d43642f000510 > [ 507.297242] 1T ESID= d00000 VSID= d43642f LLP:110 > [ 507.297243] 11 f000000008000000 400a86c85f000500 > [ 507.297244] 1T ESID= f00000 VSID= a86c85f LLP:100 > [ 507.297245] 12 00007f0008000000 4008119624000d90 > [ 507.297246] 1T ESID= 7f VSID= 8119624 LLP:110 > [ 507.297247] 13 0000000018000000 00092885f5150d90 > [ 507.297247] 256M ESID= 1 VSID= 92885f5150 LLP:110 > [ 507.297248] 14 0000010008000000 4009e7cb50000d90 > [ 507.297249] 1T ESID= 1 VSID= 9e7cb50 LLP:110 > [ 507.297250] 15 d000000008000000 400d43642f000510 > [ 507.297251] 1T ESID= d00000 VSID= d43642f LLP:110 > [ 507.297252] 16 d000000008000000 400d43642f000510 > [ 507.297253] 1T ESID= d00000 VSID= d43642f LLP:110 > [ 507.297253] ---------------------------------- > [ 507.297254] SLB cache ptr value = 3 > [ 507.297254] Valid SLB cache entries: > [ 507.297255] 00 EA[0-35]= 7f000 > [ 507.297256] 01 EA[0-35]= 1 > [ 507.297257] 02 EA[0-35]= 1000 > [ 507.297257] Rest of SLB cache entries: > [ 507.297258] 03 EA[0-35]= 7f000 > [ 507.297258] 04 EA[0-35]= 1 > [ 507.297259] 05 EA[0-35]= 1000 > [ 507.297260] 06 EA[0-35]= 12 > [ 507.297260] 07 EA[0-35]= 7f000 > > Suggested-by: Aneesh Kumar K.V > Suggested-by: Michael Ellerman > Signed-off-by: Mahesh Salgaonkar > --- > > Changes in V8: > - Limit the slb saving to single level of mce recursion. Thanks, that looks good now. Reviewed-by: Nicholas Piggin