6.10-stable review patch. If anyone has any objections, please let me know.
------------------
From: Namhyung Kim <namhyung@xxxxxxxxxx>
[ Upstream commit a11b4222bb579dcf9646f3c4ecd2212ae762a2c8 ]
The __die_find_member_offset_cb() missed to handle bitfield members
which don't have DW_AT_data_member_location. Like in adding member
types in __add_member_cb() it should fallback to check the bit offset
when it resolves the member type for an offset.
Fixes: 437683a9941891c1 ("perf dwarf-aux: Handle type transfer for memory access")
Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Athira Rajeev <atrajeev@xxxxxxxxxxxxxxxxxx>
Cc: Ian Rogers <irogers@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20240821232628.353177-2-namhyung@xxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
tools/perf/util/dwarf-aux.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/tools/perf/util/dwarf-aux.c b/tools/perf/util/dwarf-aux.c
index 0e7d2060740df..1b0e59f4d8e93 100644
--- a/tools/perf/util/dwarf-aux.c
+++ b/tools/perf/util/dwarf-aux.c
@@ -1977,8 +1977,15 @@ static int __die_find_member_offset_cb(Dwarf_Die *die_mem, void *arg)
return DIE_FIND_CB_SIBLING;
/* Unions might not have location */
- if (die_get_data_member_location(die_mem, &loc) < 0)
- loc = 0;
+ if (die_get_data_member_location(die_mem, &loc) < 0) {
+ Dwarf_Attribute attr;
+
+ if (dwarf_attr_integrate(die_mem, DW_AT_data_bit_offset, &attr) &&
+ dwarf_formudata(&attr, &loc) == 0)
+ loc /= 8;
+ else
+ loc = 0;
+ }
if (offset == loc)
return DIE_FIND_CB_END;
--
2.43.0
