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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4B55FC2FC14 for ; Thu, 17 Aug 2023 12:22:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350778AbjHQMWZ (ORCPT ); Thu, 17 Aug 2023 08:22:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40870 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1350915AbjHQMWN (ORCPT ); Thu, 17 Aug 2023 08:22:13 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BE89F2713 for ; Thu, 17 Aug 2023 05:21:51 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id B82FF63A55 for ; Thu, 17 Aug 2023 12:21:50 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D87D4C433C8; Thu, 17 Aug 2023 12:21:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1692274910; bh=2B5Gj22+SKs//miCvu0ePsQRQsA989iiI/oiqI9LnYg=; h=Date:From:To:Cc:Subject:From; b=acr764nD/rpRcvPBiF4ZktYYy81eadQ2fJSzxhP4uuCgPAxyxod0EKmWNXJXizD9d cBq7KfnxQK/RnPvuut7Xxodgj4rMOpOFwWrhpj0nxigKH+zc07Mj91H72chdNO3Ajg yfTOSrmfQNpP2Ix2eqO84eGZ2t+nqGkWKUGvGHW6DNVsBRrJhgVLNezT0weo2b7tPj IFK/ORZfZY+usd35x+Sps4DZLwkksH7OuxqAJ+mMBzG0pwS8S/Svs8+NI1ckCbMLRs Br1RcTMxMDtibMi03nQIsi6V1NyEiCfTk/Lu+le4wmfQ0Jqrmku+UeCL/GZNiC7NvO B/jkieXYPGlKw== Received: by quaco.ghostprotocols.net (Postfix, from userid 1000) id B2529404DF; Thu, 17 Aug 2023 09:21:46 -0300 (-03) Date: Thu, 17 Aug 2023 09:21:46 -0300 From: Arnaldo Carvalho de Melo To: Namhyung Kim , Mamatha Inamdar Cc: Adrian Hunter , Alexander Shishkin , Alexey Budankov , Greg Kroah-Hartman , Jeremie Galarneau , Jiri Olsa , Kate Stewart , Mukesh Ojha , Nageswara R Sastry , Peter Zijlstra , Ravi Bangoria , Shawn Landden , Song Liu , Thomas Gleixner , Tzvetomir Stoyanov , Linux Kernel Mailing List Subject: [PATCH 1/1] perf top: Don't pass an ERR_PTR() directly to perf_session__delete() Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org While debugging a segfault on 'perf lock contention' without an available perf.data file I noticed that it was basically calling: perf_session__delete(ERR_PTR(-1)) Resulting in: (gdb) run lock contention Starting program: /root/bin/perf lock contention [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib64/libthread_db.so.1". failed to open perf.data: No such file or directory (try 'perf record' first) Initializing perf session failed Program received signal SIGSEGV, Segmentation fault. 0x00000000005e7515 in auxtrace__free (session=0xffffffffffffffff) at util/auxtrace.c:2858 2858 if (!session->auxtrace) (gdb) p session $1 = (struct perf_session *) 0xffffffffffffffff (gdb) bt #0 0x00000000005e7515 in auxtrace__free (session=0xffffffffffffffff) at util/auxtrace.c:2858 #1 0x000000000057bb4d in perf_session__delete (session=0xffffffffffffffff) at util/session.c:300 #2 0x000000000047c421 in __cmd_contention (argc=0, argv=0x7fffffffe200) at builtin-lock.c:2161 #3 0x000000000047dc95 in cmd_lock (argc=0, argv=0x7fffffffe200) at builtin-lock.c:2604 #4 0x0000000000501466 in run_builtin (p=0xe597a8 , argc=2, argv=0x7fffffffe200) at perf.c:322 #5 0x00000000005016d5 in handle_internal_command (argc=2, argv=0x7fffffffe200) at perf.c:375 #6 0x0000000000501824 in run_argv (argcp=0x7fffffffe02c, argv=0x7fffffffe020) at perf.c:419 #7 0x0000000000501b11 in main (argc=2, argv=0x7fffffffe200) at perf.c:535 (gdb) So just set it to NULL after using PTR_ERR(session) to decode the error as perf_session__delete(NULL) is supported. Fixes: 6ef81c55a2b6584c ("perf session: Return error code for perf_session__new() function on failure") Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Alexey Budankov Cc: Greg Kroah-Hartman Cc: Jeremie Galarneau Cc: Jiri Olsa Cc: Kate Stewart Cc: Mamatha Inamdar Cc: Mukesh Ojha Cc: Nageswara R Sastry Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Ravi Bangoria Cc: Shawn Landden Cc: Song Liu Cc: Thomas Gleixner Cc: Tzvetomir Stoyanov Link: https://lore.kernel.org/lkml/ Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-top.c | 1 + 1 file changed, 1 insertion(+) diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c index 1baa2acb3cedd989..ea8c7eca5eeedd76 100644 --- a/tools/perf/builtin-top.c +++ b/tools/perf/builtin-top.c @@ -1805,6 +1805,7 @@ int cmd_top(int argc, const char **argv) top.session = perf_session__new(NULL, NULL); if (IS_ERR(top.session)) { status = PTR_ERR(top.session); + top.session = NULL; goto out_delete_evlist; } -- 2.37.1