| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Wed, 18 Nov 2009 20:20:52 -0200
From: Arnaldo Carvalho de Melo <acme@...radead.org>
To: Ingo Molnar <mingo@...e.hu>
Cc: linux-kernel@...r.kernel.org,
Arnaldo Carvalho de Melo <acme@...hat.com>,
Roland McGrath <roland@...hat.com>,
Frédéric Weisbecker <fweisbec@...il.com>,
Mike Galbraith <efault@....de>,
Peter Zijlstra <a.p.zijlstra@...llo.nl>,
Paul Mackerras <paulus@...ba.org>
Subject: [PATCH 3/4] perf symbols: Record the build_ids of kernel modules too
From: Arnaldo Carvalho de Melo <acme@...hat.com>
[root@...pio linux-2.6-tip]# perf record -a sleep 2s;perf buildid-list|tail
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.162 MB perf.data (~7078 samples) ]
881588fa57b3c1696bc91e5e804a11304f093535 [cfg80211]
4d47ce1da9d16bad00c962c072451b7c681e82df [snd_page_alloc]
5146377e89a7caac617f9782f1a02e46263d3a31 [rfkill]
2153b937bff0d345fea83b63a2e1d3138569f83d [i915]
4e6fb1bb97362e3ee4d306988b9ad6912d5fb9ae [drm_kms_helper]
f56ef2bf853e3a798f0d8d51f797622e5dc4420e [drm]
b0d157a3b5c4e017329ffc07c64623cd6ad65e95 [i2c_algo_bit]
8125374b905ef9fa8b65d98e166b008ad952f198 [i2c_core]
fc875c6e5a90e7b915e9d445d0efc859e1b2678c [video]
4b43c5006589f977e9762fdfc7ac1a92b72fca52 [output]
[root@...pio linux-2.6-tip]#
elfutils libdwfl/linux-kernel-modules.c was used as reference, as
suggested by Roland McGrath.
Cc: Roland McGrath <roland@...hat.com>
Cc: Frédéric Weisbecker <fweisbec@...il.com>
Cc: Mike Galbraith <efault@....de>
Cc: Peter Zijlstra <a.p.zijlstra@...llo.nl>
Cc: Paul Mackerras <paulus@...ba.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@...hat.com>
---
tools/perf/util/header.c | 5 ++++
tools/perf/util/symbol.c | 53 +++++++++++++++++++++++++++++++++++++++++++++-
tools/perf/util/symbol.h | 2 +
3 files changed, 59 insertions(+), 1 deletions(-)
diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index 31731f1..d3d656f 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -241,6 +241,11 @@ perf_header__adds_write(struct perf_header *self, int fd)
buildid_sec = &feat_sec[idx++];
+ /*
+ * Read the list of loaded modules with its build_ids
+ */
+ dsos__load_modules();
+
/* Write build-ids */
buildid_sec->offset = lseek(fd, 0, SEEK_CUR);
if (dsos__write_buildid_table(fd) < 0)
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 946ec31..7b4cede 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -9,6 +9,7 @@
#include <libelf.h>
#include <gelf.h>
#include <elf.h>
+#include <limits.h>
#include <sys/utsname.h>
enum dso_origin {
@@ -943,6 +944,50 @@ out:
return err;
}
+int sysfs__read_build_id(const char *filename, void *build_id, size_t size)
+{
+ int fd, err = -1;
+
+ if (size < BUILD_ID_SIZE)
+ goto out;
+
+ fd = open(filename, O_RDONLY);
+ if (fd < 0)
+ goto out;
+
+ while (1) {
+ char bf[BUFSIZ];
+ GElf_Nhdr nhdr;
+ int namesz, descsz;
+
+ if (read(fd, &nhdr, sizeof(nhdr)) != sizeof(nhdr))
+ break;
+
+ namesz = (nhdr.n_namesz + 3) & -4U;
+ descsz = (nhdr.n_descsz + 3) & -4U;
+ if (nhdr.n_type == NT_GNU_BUILD_ID &&
+ nhdr.n_namesz == sizeof("GNU")) {
+ if (read(fd, bf, namesz) != namesz)
+ break;
+ if (memcmp(bf, "GNU", sizeof("GNU")) == 0) {
+ if (read(fd, build_id,
+ BUILD_ID_SIZE) == BUILD_ID_SIZE) {
+ err = 0;
+ break;
+ }
+ } else if (read(fd, bf, descsz) != descsz)
+ break;
+ } else {
+ int n = namesz + descsz;
+ if (read(fd, bf, n) != n)
+ break;
+ }
+ }
+ close(fd);
+out:
+ return err;
+}
+
char dso__symtab_origin(const struct dso *self)
{
static const char origin[] = {
@@ -1218,7 +1263,7 @@ static struct map *map__new2(u64 start, struct dso *dso)
return self;
}
-static int dsos__load_modules(void)
+int dsos__load_modules(void)
{
char *line = NULL;
size_t n;
@@ -1268,6 +1313,12 @@ static int dsos__load_modules(void)
goto out_delete_line;
}
+ snprintf(name, sizeof(name),
+ "/sys/module/%s/notes/.note.gnu.build-id", line);
+ if (sysfs__read_build_id(name, dso->build_id,
+ sizeof(dso->build_id)) == 0)
+ dso->has_build_id = true;
+
dso->origin = DSO__ORIG_KMODULE;
kernel_maps__insert(map);
dsos__add(dso);
diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h
index 546eb76..da7ec1a 100644
--- a/tools/perf/util/symbol.h
+++ b/tools/perf/util/symbol.h
@@ -78,6 +78,7 @@ void dso__delete(struct dso *self);
struct symbol *dso__find_symbol(struct dso *self, u64 ip);
int dsos__load_kernel(const char *vmlinux, symbol_filter_t filter, int modules);
+int dsos__load_modules(void);
struct dso *dsos__findnew(const char *name);
int dso__load(struct dso *self, struct map *map, symbol_filter_t filter);
void dsos__fprintf(FILE *fp);
@@ -89,6 +90,7 @@ char dso__symtab_origin(const struct dso *self);
void dso__set_build_id(struct dso *self, void *build_id);
int filename__read_build_id(const char *filename, void *bf, size_t size);
+int sysfs__read_build_id(const char *filename, void *bf, size_t size);
bool dsos__read_build_ids(void);
int build_id__sprintf(u8 *self, int len, char *bf);
--
1.6.2.5
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists