From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753052AbbIOPLj (ORCPT ); Tue, 15 Sep 2015 11:11:39 -0400 Received: from casper.infradead.org ([85.118.1.10]:45116 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753373AbbIOPJO (ORCPT ); Tue, 15 Sep 2015 11:09:14 -0400 From: Arnaldo Carvalho de Melo To: Ingo Molnar Cc: linux-kernel@vger.kernel.org, Wang Nan , Namhyung Kim , Zefan Li , pi3orama@163.com, Arnaldo Carvalho de Melo Subject: [PATCH 01/15] perf top: Fix segfault pressing -> with no hist entries Date: Tue, 15 Sep 2015 12:08:46 -0300 Message-Id: <1442329740-18042-2-git-send-email-acme@kernel.org> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1442329740-18042-1-git-send-email-acme@kernel.org> References: <1442329740-18042-1-git-send-email-acme@kernel.org> X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Wang Nan 'perf top' segfaults with following operation: # perf top -e page-faults -p 11400 # 11400 never generates page-fault Then on the resulting empty interface, press right key: # ./perf top -e page-faults -p 11400 perf: Segmentation fault -------- backtrace -------- ./perf[0x535428] /lib64/libc.so.6(+0x3545f)[0x7f0dd360745f] ./perf[0x531d46] ./perf(perf_evlist__tui_browse_hists+0x96)[0x5340d6] ./perf[0x44ba2f] /lib64/libpthread.so.0(+0x81d0)[0x7f0dd49dc1d0] /lib64/libc.so.6(clone+0x6c)[0x7f0dd36b90dc] The bug resides in perf_evsel__hists_browse() that, in the above circumstance browser->selection can be NULL, but code after skip_annotation doesn't consider it. This patch fix it by checking browser->selection before fetching browser->selection->map. Signed-off-by: Wang Nan Tested-by: Arnaldo Carvalho de Melo Cc: Namhyung Kim Cc: Zefan Li Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1442226235-117265-1-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/ui/browsers/hists.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/tools/perf/ui/browsers/hists.c b/tools/perf/ui/browsers/hists.c index cf86f2d3a5e7..c04c60d4863c 100644 --- a/tools/perf/ui/browsers/hists.c +++ b/tools/perf/ui/browsers/hists.c @@ -1968,7 +1968,8 @@ skip_annotation: &options[nr_options], dso); nr_options += add_map_opt(browser, &actions[nr_options], &options[nr_options], - browser->selection->map); + browser->selection ? + browser->selection->map : NULL); /* perf script support */ if (browser->he_selection) { @@ -1976,6 +1977,15 @@ skip_annotation: &actions[nr_options], &options[nr_options], thread, NULL); + /* + * Note that browser->selection != NULL + * when browser->he_selection is not NULL, + * so we don't need to check browser->selection + * before fetching browser->selection->sym like what + * we do before fetching browser->selection->map. + * + * See hist_browser__show_entry. + */ nr_options += add_script_opt(browser, &actions[nr_options], &options[nr_options], -- 2.1.0