leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

perf symbols: Fix annotation of thumb code

Browse Source 
In ARM's Thumb mode the bottom bit of the symbol address is set to mark
the function as Thumb; the instructions are in reality 2 or 4 byte on 2
byte alignments, and when the +1 address is used in annotate it causes
objdump to disassemble invalid instructions.

The patch removes that bottom bit during symbol loading.

Many thinks to Dave Martin for comments on an initial version of the
patch.

(For reference this corresponds to this bug
https://bugs.launchpad.net/linux-linaro/+bug/677547 )

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Dave Martin <dave.martin@linaro.org>
LKML-Reference: <20110121163922.GA31398@davesworkthinkpad>
Signed-off-by: Dr. David Alan Gilbert <david.gilbert@linaro.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Dr. David Alan Gilbert 2011-01-21 16:40:19 +00:00 committed by Arnaldo Carvalho de Melo
parent 547e9fd7d3
commit b2f8fb237e
1 changed files with 7 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
tools/perf/util/symbol.c
View File

@ -1161,6 +1161,13 @@ static int dso__load_sym(struct dso *self, struct map *map, const char *name,
section_name = elf_sec__name(&shdr, secstrs);
/* On ARM, symbols for thumb functions have 1 added to
* the symbol address as a flag - remove it */
if ((ehdr.e_machine == EM_ARM) &&
(map->type == MAP__FUNCTION) &&
(sym.st_value & 1))
--sym.st_value;
if (self->kernel != DSO_TYPE_USER || kmodule) {
char dso_name[PATH_MAX];