[PATCH 6.9 036/374] perf map: Remove kernel map before updating start and end addresses

Greg Kroah-Hartman
2024-06-06T14:08:29Z

From: James Clark <james.clark@arm.com>

[ Upstream commit df12e21d4e15e48a5e7d12e58f1a00742c4177d0 ]

In a debug build there is validation that mmap lists are sorted when
taking a lock. In machine__update_kernel_mmap() the start and end
addresses are updated resulting in an unsorted list before the map is
removed from the list. When the map is removed, the lock is taken which
triggers the validation and the failure:

$ perf test "object code reading"
--- start ---
perf: util/maps.c:88: check_invariants: Assertion `map__start(prev) <= map__start(map)' failed.
Aborted

Fix it by updating the addresses after removal, but before insertion.
The bug depends on the ordering and type of debug info on the system and
doesn't reproduce everywhere.

Fixes: 659ad3492b913c90 ("perf maps: Switch from rbtree to lazily sorted array for addresses")
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: James Clark <james.clark@arm.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linux.dev>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Spoorthy S <spoorts2@in.ibm.com>
Link: https://lore.kernel.org/r/20240410103458.813656-4-james.clark@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
tools/perf/util/machine.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index 527517db31821..07c22f765fab4 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -1549,8 +1549,8 @@ static int machine__update_kernel_mmap(struct machine *machine,
updated = map__get(orig);

machine->vmlinux_map = updated;
- machine__set_kernel_mmap(machine, start, end);
maps__remove(machine__kernel_maps(machine), orig);
+ machine__set_kernel_mmap(machine, start, end);
err = maps__insert(machine__kernel_maps(machine), updated);
map__put(orig);

--
2.43.0