Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755527AbbLDM6z (ORCPT ); Fri, 4 Dec 2015 07:58:55 -0500 Received: from mail-pf0-f172.google.com ([209.85.192.172]:35275 "EHLO mail-pf0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751889AbbLDM6x (ORCPT ); Fri, 4 Dec 2015 07:58:53 -0500 Date: Fri, 4 Dec 2015 21:50:53 +0900 From: Namhyung Kim To: Wang Nan Cc: acme@redhat.com, acme@kernel.org, linux-kernel@vger.kernel.org, pi3orama@163.com, lizefan@huawei.com Subject: Re: [PATCH v2 1/3] perf hists browser: Fix segfault if use symbol filter in cmdline Message-ID: <20151204125053.GB22102@danjae.kornet> References: <1449112095-238769-1-git-send-email-wangnan0@huawei.com> <1449112095-238769-2-git-send-email-wangnan0@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1449112095-238769-2-git-send-email-wangnan0@huawei.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2121 Lines: 64 On Thu, Dec 03, 2015 at 03:08:13AM +0000, Wang Nan wrote: > If feed perf a symbol filter in cmdline and the result is empty, > pressing 'Enter' in the hist browser causes crash: > > # ./perf report perf.data <-- Common mistake for beginners > > Then press 'Enter': > > perf: Segmentation fault > -------- backtrace -------- > /home/wangnan/perf[0x53e578] > /lib64/libc.so.6(+0x3545f)[0x7f76bafe045f] > /home/wangnan/perf[0x539dd4] > /home/wangnan/perf(perf_evlist__tui_browse_hists+0x96)[0x53d216] > /home/wangnan/perf(cmd_report+0x1b9f)[0x442c7f] > /home/wangnan/perf[0x47efa2] > /home/wangnan/perf(main+0x5f5)[0x432fa5] > /lib64/libc.so.6(__libc_start_main+0xf4)[0x7f76bafccbd4] > /home/wangnan/perf[0x4330d4] > > This is because 'perf.data' is interperted as a symbol filter, and the > result is empty, so selection is empty. However, > hist_browser__toggle_fold() forgets to check it. > > This patch simply return false when selection is NULL. > > Signed-off-by: Wang Nan > Acked-by: Namhyung Kim > Cc: Arnaldo Carvalho de Melo > --- > tools/perf/ui/browsers/hists.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/tools/perf/ui/browsers/hists.c b/tools/perf/ui/browsers/hists.c > index dcdcbaf..601a585 100644 > --- a/tools/perf/ui/browsers/hists.c > +++ b/tools/perf/ui/browsers/hists.c > @@ -340,6 +340,9 @@ static bool hist_browser__toggle_fold(struct hist_browser *browser) > struct callchain_list *cl = container_of(ms, struct callchain_list, ms); > bool has_children; > > + if (!ms) > + return false; > + I'm ok with this change itself. But as other code checks the browser->he_selection, it'd be better to check 'he' here for consistency. Thanks, Namhyung > if (ms == &he->ms) > has_children = hist_entry__toggle_fold(he); > else > -- > 1.8.3.4 > -- 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/