aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorAdrian Hunter <[email protected]>2014-01-29 16:14:41 +0200
committerArnaldo Carvalho de Melo <[email protected]>2014-01-31 17:21:51 -0300
commita00d28cb72d3629c6481fe21ba6c6b4f96caed49 (patch)
tree9e37aba781546006aafea081ee2cbcb3b9c2b893
parent0ae617bedde062003fd70e566e9a2601e273ea0e (diff)
perf symbols: Prevent the use of kcore if the kernel has moved
Use of kcore is predicated upon it matching the recorded data. If the kernel has been relocated at boot time (i.e. since the data was recorded) then do not use kcore. Note that it is possible to make a copy of kcore at the time the data is recorded using 'perf buildid-cache'. Then the perf tools will use the copy because it does match the data. Signed-off-by: Adrian Hunter <[email protected]> Tested-by: Jiri Olsa <[email protected]> Cc: David Ahern <[email protected]> Cc: Frederic Weisbecker <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Mike Galbraith <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Stephane Eranian <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
-rw-r--r--tools/perf/util/symbol.c25
1 files changed, 21 insertions, 4 deletions
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 39ce9adbaaf0..4ac1f871ec27 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -976,6 +976,23 @@ static int validate_kcore_modules(const char *kallsyms_filename,
return 0;
}
+static int validate_kcore_addresses(const char *kallsyms_filename,
+ struct map *map)
+{
+ struct kmap *kmap = map__kmap(map);
+
+ if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) {
+ u64 start;
+
+ start = kallsyms__get_function_start(kallsyms_filename,
+ kmap->ref_reloc_sym->name);
+ if (start != kmap->ref_reloc_sym->addr)
+ return -EINVAL;
+ }
+
+ return validate_kcore_modules(kallsyms_filename, map);
+}
+
struct kcore_mapfn_data {
struct dso *dso;
enum map_type type;
@@ -1019,8 +1036,8 @@ static int dso__load_kcore(struct dso *dso, struct map *map,
kallsyms_filename))
return -EINVAL;
- /* All modules must be present at their original addresses */
- if (validate_kcore_modules(kallsyms_filename, map))
+ /* Modules and kernel must be present at their original addresses */
+ if (validate_kcore_addresses(kallsyms_filename, map))
return -EINVAL;
md.dso = dso;
@@ -1424,7 +1441,7 @@ static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz)
continue;
scnprintf(kallsyms_filename, sizeof(kallsyms_filename),
"%s/%s/kallsyms", dir, dent->d_name);
- if (!validate_kcore_modules(kallsyms_filename, map)) {
+ if (!validate_kcore_addresses(kallsyms_filename, map)) {
strlcpy(dir, kallsyms_filename, dir_sz);
ret = 0;
break;
@@ -1479,7 +1496,7 @@ static char *dso__find_kallsyms(struct dso *dso, struct map *map)
if (fd != -1) {
close(fd);
/* If module maps match go with /proc/kallsyms */
- if (!validate_kcore_modules("/proc/kallsyms", map))
+ if (!validate_kcore_addresses("/proc/kallsyms", map))
goto proc_kallsyms;
}