From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932921AbcECBlA (ORCPT ); Mon, 2 May 2016 21:41:00 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:60042 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932897AbcECAXG (ORCPT ); Mon, 2 May 2016 20:23:06 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Andi Kleen , Adrian Hunter , Jiri Olsa , Arnaldo Carvalho de Melo Subject: [PATCH 4.4 083/163] perf intel-pt: Fix segfault tracing transactions Date: Mon, 2 May 2016 17:11:51 -0700 Message-Id: <20160503000511.229997001@linuxfoundation.org> X-Mailer: git-send-email 2.8.2 In-Reply-To: <20160503000508.556845508@linuxfoundation.org> References: <20160503000508.556845508@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Adrian Hunter commit 1342e0b7a6c1a060c593037fbac9f4b717f1cb3b upstream. Tracing a workload that uses transactions gave a seg fault as follows: perf record -e intel_pt// workload perf report Program received signal SIGSEGV, Segmentation fault. 0x000000000054b58c in intel_pt_reset_last_branch_rb (ptq=0x1a36110) at util/intel-pt.c:929 929 ptq->last_branch_rb->nr = 0; (gdb) p ptq->last_branch_rb $1 = (struct branch_stack *) 0x0 (gdb) up 1148 intel_pt_reset_last_branch_rb(ptq); (gdb) l 1143 if (ret) 1144 pr_err("Intel Processor Trace: failed to deliver transaction event 1145 ret); 1146 1147 if (pt->synth_opts.callchain) 1148 intel_pt_reset_last_branch_rb(ptq); 1149 1150 return ret; 1151 } 1152 (gdb) p pt->synth_opts.callchain $2 = true (gdb) (gdb) bt #0 0x000000000054b58c in intel_pt_reset_last_branch_rb (ptq=0x1a36110) #1 0x000000000054c1e0 in intel_pt_synth_transaction_sample (ptq=0x1a36110) #2 0x000000000054c5b2 in intel_pt_sample (ptq=0x1a36110) Caused by checking the 'callchain' flag when it should have been the 'last_branch' flag. Fix that. Reported-by: Andi Kleen Signed-off-by: Adrian Hunter Cc: Jiri Olsa Fixes: f14445ee72c5 ("perf intel-pt: Support generating branch stack") Link: http://lkml.kernel.org/r/1460977068-11566-1-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Greg Kroah-Hartman --- tools/perf/util/intel-pt.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/tools/perf/util/intel-pt.c +++ b/tools/perf/util/intel-pt.c @@ -1127,7 +1127,7 @@ static int intel_pt_synth_transaction_sa pr_err("Intel Processor Trace: failed to deliver transaction event, error %d\n", ret); - if (pt->synth_opts.callchain) + if (pt->synth_opts.last_branch) intel_pt_reset_last_branch_rb(ptq); return ret;