Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932326AbbDMLqk (ORCPT ); Mon, 13 Apr 2015 07:46:40 -0400 Received: from szxga01-in.huawei.com ([58.251.152.64]:46893 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932185AbbDMLqf (ORCPT ); Mon, 13 Apr 2015 07:46:35 -0400 From: He Kuang To: , , , , CC: , Subject: [PATCH 3/3] perf probe: Fix segfault when probe with lazy_line to file Date: Mon, 13 Apr 2015 19:41:30 +0800 Message-ID: <1428925290-5623-3-git-send-email-hekuang@huawei.com> X-Mailer: git-send-email 2.3.3.220.g9ab698f In-Reply-To: <1428925290-5623-1-git-send-email-hekuang@huawei.com> References: <1428925290-5623-1-git-send-email-hekuang@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.107.197.189] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1672 Lines: 47 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 repoduced 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 --- 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 431c12d..e91101b 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); -- 2.3.3.220.g9ab698f -- 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/