From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753810AbcDRLBj (ORCPT ); Mon, 18 Apr 2016 07:01:39 -0400 Received: from mga04.intel.com ([192.55.52.120]:10307 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753649AbcDRLBh (ORCPT ); Mon, 18 Apr 2016 07:01:37 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.24,502,1455004800"; d="scan'208";a="934725625" From: Adrian Hunter To: Arnaldo Carvalho de Melo Cc: Jiri Olsa , linux-kernel@vger.kernel.org, Andi Kleen Subject: [PATCH] perf: intel-pt: Fix seg fault tracing transactions Date: Mon, 18 Apr 2016 13:57:48 +0300 Message-Id: <1460977068-11566-1-git-send-email-adrian.hunter@intel.com> X-Mailer: git-send-email 1.9.1 Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 Fixes: f14445ee72c5 ("perf intel-pt: Support generating branch stack") Signed-off-by: Adrian Hunter Cc: stable@vger.kernel.org # v4.4+ --- tools/perf/util/intel-pt.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/perf/util/intel-pt.c b/tools/perf/util/intel-pt.c index ddec87f6e616..137196990012 100644 --- a/tools/perf/util/intel-pt.c +++ b/tools/perf/util/intel-pt.c @@ -1144,7 +1144,7 @@ static int intel_pt_synth_transaction_sample(struct intel_pt_queue *ptq) 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; -- 1.9.1