Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754627AbbDMWPm (ORCPT ); Mon, 13 Apr 2015 18:15:42 -0400 Received: from mail.kernel.org ([198.145.29.136]:38517 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751965AbbDMWPf (ORCPT ); Mon, 13 Apr 2015 18:15:35 -0400 From: Arnaldo Carvalho de Melo To: Ingo Molnar Cc: linux-kernel@vger.kernel.org, He Kuang , Namhyung Kim , Peter Zijlstra , Wang Nan , Arnaldo Carvalho de Melo Subject: [PATCH 5/5] perf probe: Fix segfault when probe with lazy_line to file Date: Mon, 13 Apr 2015 19:15:02 -0300 Message-Id: <1428963302-31538-6-git-send-email-acme@kernel.org> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1428963302-31538-1-git-send-email-acme@kernel.org> References: <1428963302-31538-1-git-send-email-acme@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2081 Lines: 56 From: He Kuang The first argument passed to find_probe_point_lazy() should be CU die, which will be passed to die_walk_lines() when lazy_line matches. Currently, when we probe with lazy_line pattern to file without function name, NULL pointer is passed and causes a segment fault. Can be reproduced as following: $ perf probe -k vmlinux --add='fs/super.c;s->s_count=1;' [ 1958.984658] perf[1020]: segfault at 10 ip 00007fc6e10d8c71 sp 00007ffcbfaaf900 error 4 in libdw-0.161.so[7fc6e10ce000+34000] Segmentation fault After this patch: $ perf probe -k vmlinux --add='fs/super.c;s->s_count=1;' Added new event: probe:_stext (on @fs/super.c) You can now use it in all perf tools, such as: perf record -e probe:_stext -aR sleep 1 Signed-off-by: He Kuang Tested-by: Arnaldo Carvalho de Melo Acked-by: Masami Hiramatsu Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Wang Nan Link: http://lkml.kernel.org/r/1428925290-5623-3-git-send-email-hekuang@huawei.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/probe-finder.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c index 431c12d299a2..e91101b8f60f 100644 --- a/tools/perf/util/probe-finder.c +++ b/tools/perf/util/probe-finder.c @@ -1067,7 +1067,7 @@ static int debuginfo__find_probes(struct debuginfo *dbg, if (pp->function) ret = find_probe_point_by_func(pf); else if (pp->lazy_line) - ret = find_probe_point_lazy(NULL, pf); + ret = find_probe_point_lazy(&pf->cu_die, pf); else { pf->lno = pp->line; ret = find_probe_point_by_line(pf); -- 1.9.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/