From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1033504AbbKEQDK (ORCPT ); Thu, 5 Nov 2015 11:03:10 -0500 Received: from bombadil.infradead.org ([198.137.202.9]:43472 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1031507AbbKEQDF (ORCPT ); Thu, 5 Nov 2015 11:03:05 -0500 From: Arnaldo Carvalho de Melo To: Ingo Molnar Cc: linux-kernel@vger.kernel.org, Jiri Olsa , Jiri Olsa , Andrew Morton , Peter Zijlstra , Thomas Gleixner , Arnaldo Carvalho de Melo Subject: [PATCH 06/12] perf tools: Insert split maps correctly into origin group Date: Thu, 5 Nov 2015 13:02:16 -0300 Message-Id: <1446739342-29279-7-git-send-email-acme@kernel.org> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1446739342-29279-1-git-send-email-acme@kernel.org> References: <1446739342-29279-1-git-send-email-acme@kernel.org> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.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: Jiri Olsa When new maps are cloned out of split map they are added into origin map's group, but their groups pointer is not updated. This could lead to a segfault, because map->groups is expected to be always set as reported by Markus: __map__is_kernel (map=map@entry=0x1abb7a0) at util/map.c:238 238 return __machine__kernel_map(map->groups->machine, map->type) = (gdb) bt #0 __map__is_kernel (map=map@entry=0x1abb7a0) at util/map.c:238 #1 0x00000000004393e4 in symbol_filter (map=map@entry=0x1abb7a0, sym=sym@entry #2 0x00000000004fcd4d in dso__load_sym (dso=dso@entry=0x166dae0, map=map@entry #3 0x00000000004a64e0 in dso__load (dso=0x166dae0, map=map@entry=0x1abb7a0, fi #4 0x00000000004b941f in map__load (filter=0x4393c0 , map=groups pointer update. It takes no lock as opposed to existing map_groups__insert, as maps__fixup_overlappings(), where it is being called, already has the necessary lock held. Using __map_groups__insert to add new maps after map split. Reported-by: Markus Trippelsdorf Signed-off-by: Jiri Olsa Tested-by: Markus Trippelsdorf Cc: Andrew Morton Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/20151104140811.GA32664@krava.brq.redhat.com Fixes: cfc5acd4c80b ("perf top: Filter symbols based on __map__is_kernel(map)") Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/map.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c index 4e38c396a897..afc6b56cf749 100644 --- a/tools/perf/util/map.c +++ b/tools/perf/util/map.c @@ -644,6 +644,12 @@ size_t map_groups__fprintf(struct map_groups *mg, FILE *fp) return printed; } +static void __map_groups__insert(struct map_groups *mg, struct map *map) +{ + __maps__insert(&mg->maps[map->type], map); + map->groups = mg; +} + static int maps__fixup_overlappings(struct maps *maps, struct map *map, FILE *fp) { struct rb_root *root; @@ -682,7 +688,7 @@ static int maps__fixup_overlappings(struct maps *maps, struct map *map, FILE *fp } before->end = map->start; - __maps__insert(maps, before); + __map_groups__insert(pos->groups, before); if (verbose >= 2) map__fprintf(before, fp); } @@ -696,7 +702,7 @@ static int maps__fixup_overlappings(struct maps *maps, struct map *map, FILE *fp } after->start = map->end; - __maps__insert(maps, after); + __map_groups__insert(pos->groups, after); if (verbose >= 2) map__fprintf(after, fp); } -- 2.1.0