From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-11.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9CDBFC3A5A2 for ; Fri, 20 Sep 2019 16:23:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7336E208C0 for ; Fri, 20 Sep 2019 16:23:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2405719AbfITQXI (ORCPT ); Fri, 20 Sep 2019 12:23:08 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:52774 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404706AbfITQVL (ORCPT ); Fri, 20 Sep 2019 12:21:11 -0400 Received: from [5.158.153.53] (helo=tip-bot2.lab.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1iBLeU-00040r-Pe; Fri, 20 Sep 2019 18:20:59 +0200 Received: from [127.0.1.1] (localhost [IPv6:::1]) by tip-bot2.lab.linutronix.de (Postfix) with ESMTP id 701491C0E2B; Fri, 20 Sep 2019 18:20:57 +0200 (CEST) Date: Fri, 20 Sep 2019 16:20:57 -0000 From: "tip-bot2 for Srikar Dronamraju" Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: perf/urgent] perf stat: Fix a segmentation fault when using repeat forever Cc: Srikar Dronamraju , Jiri Olsa , Arnaldo Carvalho de Melo , Ravi Bangoria , Namhyung Kim , "Naveen N. Rao" , stable@vger.kernel.org, #@tip-bot2.tec.linutronix.de, v4.2+@tip-bot2.tec.linutronix.de, Ingo Molnar , Borislav Petkov , linux-kernel@vger.kernel.org In-Reply-To: <20190904094738.9558-3-srikar@linux.vnet.ibm.com> References: <20190904094738.9558-3-srikar@linux.vnet.ibm.com> MIME-Version: 1.0 Message-ID: <156899645738.24167.5948421311795247905.tip-bot2@tip-bot2> X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the perf/urgent branch of tip: Commit-ID: 443f2d5ba13d65ccfd879460f77941875159d154 Gitweb: https://git.kernel.org/tip/443f2d5ba13d65ccfd879460f77941875159d154 Author: Srikar Dronamraju AuthorDate: Wed, 04 Sep 2019 15:17:38 +05:30 Committer: Arnaldo Carvalho de Melo CommitterDate: Fri, 20 Sep 2019 10:28:26 -03:00 perf stat: Fix a segmentation fault when using repeat forever Observe a segmentation fault when 'perf stat' is asked to repeat forever with the interval option. Without fix: # perf stat -r 0 -I 5000 -e cycles -a sleep 10 # time counts unit events 5.000211692 3,13,89,82,34,157 cycles 10.000380119 1,53,98,52,22,294 cycles 10.040467280 17,16,79,265 cycles Segmentation fault This problem was only observed when we use forever option aka -r 0 and works with limited repeats. Calling print_counter with ts being set to NULL, is not a correct option when interval is set. Hence avoid print_counter(NULL,..) if interval is set. With fix: # perf stat -r 0 -I 5000 -e cycles -a sleep 10 # time counts unit events 5.019866622 3,15,14,43,08,697 cycles 10.039865756 3,15,16,31,95,261 cycles 10.059950628 1,26,05,47,158 cycles 5.009902655 3,14,52,62,33,932 cycles 10.019880228 3,14,52,22,89,154 cycles 10.030543876 66,90,18,333 cycles 5.009848281 3,14,51,98,25,437 cycles 10.029854402 3,15,14,93,04,918 cycles 5.009834177 3,14,51,95,92,316 cycles Committer notes: Did the 'git bisect' to find the cset introducing the problem to add the Fixes tag below, and at that time the problem reproduced as: (gdb) run stat -r0 -I500 sleep 1 Program received signal SIGSEGV, Segmentation fault. print_interval (prefix=prefix@entry=0x7fffffffc8d0 "", ts=ts@entry=0x0) at builtin-stat.c:866 866 sprintf(prefix, "%6lu.%09lu%s", ts->tv_sec, ts->tv_nsec, csv_sep); (gdb) bt #0 print_interval (prefix=prefix@entry=0x7fffffffc8d0 "", ts=ts@entry=0x0) at builtin-stat.c:866 #1 0x000000000041860a in print_counters (ts=ts@entry=0x0, argc=argc@entry=2, argv=argv@entry=0x7fffffffd640) at builtin-stat.c:938 #2 0x0000000000419a7f in cmd_stat (argc=2, argv=0x7fffffffd640, prefix=) at builtin-stat.c:1411 #3 0x000000000045c65a in run_builtin (p=p@entry=0x6291b8 , argc=argc@entry=5, argv=argv@entry=0x7fffffffd640) at perf.c:370 #4 0x000000000045c893 in handle_internal_command (argc=5, argv=0x7fffffffd640) at perf.c:429 #5 0x000000000045c8f1 in run_argv (argcp=argcp@entry=0x7fffffffd4ac, argv=argv@entry=0x7fffffffd4a0) at perf.c:473 #6 0x000000000045cac9 in main (argc=, argv=) at perf.c:588 (gdb) Mostly the same as just before this patch: Program received signal SIGSEGV, Segmentation fault. 0x00000000005874a7 in print_interval (config=0xa1f2a0 , evlist=0xbc9b90, prefix=0x7fffffffd1c0 "`", ts=0x0) at util/stat-display.c:964 964 sprintf(prefix, "%6lu.%09lu%s", ts->tv_sec, ts->tv_nsec, config->csv_sep); (gdb) bt #0 0x00000000005874a7 in print_interval (config=0xa1f2a0 , evlist=0xbc9b90, prefix=0x7fffffffd1c0 "`", ts=0x0) at util/stat-display.c:964 #1 0x0000000000588047 in perf_evlist__print_counters (evlist=0xbc9b90, config=0xa1f2a0 , _target=0xa1f0c0 , ts=0x0, argc=2, argv=0x7fffffffd670) at util/stat-display.c:1172 #2 0x000000000045390f in print_counters (ts=0x0, argc=2, argv=0x7fffffffd670) at builtin-stat.c:656 #3 0x0000000000456bb5 in cmd_stat (argc=2, argv=0x7fffffffd670) at builtin-stat.c:1960 #4 0x00000000004dd2e0 in run_builtin (p=0xa30e00 , argc=5, argv=0x7fffffffd670) at perf.c:310 #5 0x00000000004dd54d in handle_internal_command (argc=5, argv=0x7fffffffd670) at perf.c:362 #6 0x00000000004dd694 in run_argv (argcp=0x7fffffffd4cc, argv=0x7fffffffd4c0) at perf.c:406 #7 0x00000000004dda11 in main (argc=5, argv=0x7fffffffd670) at perf.c:531 (gdb) Fixes: d4f63a4741a8 ("perf stat: Introduce print_counters function") Signed-off-by: Srikar Dronamraju Acked-by: Jiri Olsa Tested-by: Arnaldo Carvalho de Melo Tested-by: Ravi Bangoria Cc: Namhyung Kim Cc: Naveen N. Rao Cc: stable@vger.kernel.org # v4.2+ Link: http://lore.kernel.org/lkml/20190904094738.9558-3-srikar@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-stat.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c index fa4b148..60cdd38 100644 --- a/tools/perf/builtin-stat.c +++ b/tools/perf/builtin-stat.c @@ -1956,7 +1956,7 @@ int cmd_stat(int argc, const char **argv) perf_evlist__reset_prev_raw_counts(evsel_list); status = run_perf_stat(argc, argv, run_idx); - if (forever && status != -1) { + if (forever && status != -1 && !interval) { print_counters(NULL, argc, argv); perf_stat__reset_stats(); }