perf tools: Deal with kernel module names in '[]' correctly
Before patchba92732e98('perf kmaps: Check kmaps to make code more robust'), 'perf report' and 'perf annotate' will segfault if trace data contains kernel module information like this: # perf report -D -i ./perf.data ... 0 0 0x188 [0x50]: PERF_RECORD_MMAP -1/0: [0xffffffbff1018000(0xf068000) @ 0]: x [test_module] ... # perf report -i ./perf.data --objdump=/path/to/objdump --kallsyms=/path/to/kallsyms perf: Segmentation fault -------- backtrace -------- /path/to/perf[0x503478] /lib64/libc.so.6(+0x3545f)[0x7fb201f3745f] /path/to/perf[0x499b56] /path/to/perf(dso__load_kallsyms+0x13c)[0x49b56c] /path/to/perf(dso__load+0x72e)[0x49c21e] /path/to/perf(map__load+0x6e)[0x4ae9ee] /path/to/perf(thread__find_addr_map+0x24c)[0x47deec] /path/to/perf(perf_event__preprocess_sample+0x88)[0x47e238] /path/to/perf[0x43ad02] /path/to/perf[0x4b55bc] /path/to/perf(ordered_events__flush+0xca)[0x4b57ea] /path/to/perf[0x4b1a01] /path/to/perf(perf_session__process_events+0x3be)[0x4b428e] /path/to/perf(cmd_report+0xf11)[0x43bfc1] /path/to/perf[0x474702] /path/to/perf(main+0x5f5)[0x42de95] /lib64/libc.so.6(__libc_start_main+0xf4)[0x7fb201f23bd4] /path/to/perf[0x42dfc4] This is because __kmod_path__parse treats '[' leading names as kernel name instead of names of kernel module. If perf.data contains build information and the buildid of such modules can be found, the dso->kernel of it will be set to DSO_TYPE_KERNEL by __event_process_build_id(), not kernel module. It will then be passed to dso__load() -> dso__load_kernel_sym() -> dso__load_kcore() if --kallsyms is provided. The refered patch adds NULL pointer checker to avoid segfault. However, such kernel modules are still processed incorrectly. This patch fixes __kmod_path__parse, makes it treat names like '[test_module]' as kernel modules. kmod-path.c is also update to reflect the above changes. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Link: http://lkml.kernel.org/r/1433321541-170245-1-git-send-email-wangnan0@huawei.com [ Fixed the merged with0443f36b0d("perf machine: Fix the search for the kernel DSO on the unified list" ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Wang Nan
Arnaldo Carvalho de Melo
parent
4fc62a89dc
commit
1f121b03d0
|
|
@ -34,9 +34,21 @@ static int test(const char *path, bool alloc_name, bool alloc_ext,
|
|||
return 0;
|
||||
}
|
||||
|
||||
static int test_is_kernel_module(const char *path, int cpumode, bool expect)
|
||||
{
|
||||
TEST_ASSERT_VAL("is_kernel_module",
|
||||
(!!is_kernel_module(path, cpumode)) == (!!expect));
|
||||
pr_debug("%s (cpumode: %d) - is_kernel_module: %s\n",
|
||||
path, cpumode, expect ? "true" : "false");
|
||||
return 0;
|
||||
}
|
||||
|
||||
#define T(path, an, ae, k, c, n, e) \
|
||||
TEST_ASSERT_VAL("failed", !test(path, an, ae, k, c, n, e))
|
||||
|
||||
#define M(path, c, e) \
|
||||
TEST_ASSERT_VAL("failed", !test_is_kernel_module(path, c, e))
|
||||
|
||||
int test__kmod_path__parse(void)
|
||||
{
|
||||
/* path alloc_name alloc_ext kmod comp name ext */
|
||||
|
|
@ -44,30 +56,90 @@ int test__kmod_path__parse(void)
|
|||
T("/xxxx/xxxx/x-x.ko", false , true , true, false, NULL , NULL);
|
||||
T("/xxxx/xxxx/x-x.ko", true , false , true, false, "[x_x]", NULL);
|
||||
T("/xxxx/xxxx/x-x.ko", false , false , true, false, NULL , NULL);
|
||||
M("/xxxx/xxxx/x-x.ko", PERF_RECORD_MISC_CPUMODE_UNKNOWN, true);
|
||||
M("/xxxx/xxxx/x-x.ko", PERF_RECORD_MISC_KERNEL, true);
|
||||
M("/xxxx/xxxx/x-x.ko", PERF_RECORD_MISC_USER, false);
|
||||
|
||||
/* path alloc_name alloc_ext kmod comp name ext */
|
||||
T("/xxxx/xxxx/x.ko.gz", true , true , true, true, "[x]", "gz");
|
||||
T("/xxxx/xxxx/x.ko.gz", false , true , true, true, NULL , "gz");
|
||||
T("/xxxx/xxxx/x.ko.gz", true , false , true, true, "[x]", NULL);
|
||||
T("/xxxx/xxxx/x.ko.gz", false , false , true, true, NULL , NULL);
|
||||
M("/xxxx/xxxx/x.ko.gz", PERF_RECORD_MISC_CPUMODE_UNKNOWN, true);
|
||||
M("/xxxx/xxxx/x.ko.gz", PERF_RECORD_MISC_KERNEL, true);
|
||||
M("/xxxx/xxxx/x.ko.gz", PERF_RECORD_MISC_USER, false);
|
||||
|
||||
/* path alloc_name alloc_ext kmod comp name ext */
|
||||
T("/xxxx/xxxx/x.gz", true , true , false, true, "x.gz" ,"gz");
|
||||
T("/xxxx/xxxx/x.gz", false , true , false, true, NULL ,"gz");
|
||||
T("/xxxx/xxxx/x.gz", true , false , false, true, "x.gz" , NULL);
|
||||
T("/xxxx/xxxx/x.gz", false , false , false, true, NULL , NULL);
|
||||
M("/xxxx/xxxx/x.gz", PERF_RECORD_MISC_CPUMODE_UNKNOWN, false);
|
||||
M("/xxxx/xxxx/x.gz", PERF_RECORD_MISC_KERNEL, false);
|
||||
M("/xxxx/xxxx/x.gz", PERF_RECORD_MISC_USER, false);
|
||||
|
||||
/* path alloc_name alloc_ext kmod comp name ext */
|
||||
T("x.gz", true , true , false, true, "x.gz", "gz");
|
||||
T("x.gz", false , true , false, true, NULL , "gz");
|
||||
T("x.gz", true , false , false, true, "x.gz", NULL);
|
||||
T("x.gz", false , false , false, true, NULL , NULL);
|
||||
M("x.gz", PERF_RECORD_MISC_CPUMODE_UNKNOWN, false);
|
||||
M("x.gz", PERF_RECORD_MISC_KERNEL, false);
|
||||
M("x.gz", PERF_RECORD_MISC_USER, false);
|
||||
|
||||
/* path alloc_name alloc_ext kmod comp name ext */
|
||||
T("x.ko.gz", true , true , true, true, "[x]", "gz");
|
||||
T("x.ko.gz", false , true , true, true, NULL , "gz");
|
||||
T("x.ko.gz", true , false , true, true, "[x]", NULL);
|
||||
T("x.ko.gz", false , false , true, true, NULL , NULL);
|
||||
M("x.ko.gz", PERF_RECORD_MISC_CPUMODE_UNKNOWN, true);
|
||||
M("x.ko.gz", PERF_RECORD_MISC_KERNEL, true);
|
||||
M("x.ko.gz", PERF_RECORD_MISC_USER, false);
|
||||
|
||||
/* path alloc_name alloc_ext kmod comp name ext */
|
||||
T("[test_module]", true , true , true, false, "[test_module]", NULL);
|
||||
T("[test_module]", false , true , true, false, NULL , NULL);
|
||||
T("[test_module]", true , false , true, false, "[test_module]", NULL);
|
||||
T("[test_module]", false , false , true, false, NULL , NULL);
|
||||
M("[test_module]", PERF_RECORD_MISC_CPUMODE_UNKNOWN, true);
|
||||
M("[test_module]", PERF_RECORD_MISC_KERNEL, true);
|
||||
M("[test_module]", PERF_RECORD_MISC_USER, false);
|
||||
|
||||
/* path alloc_name alloc_ext kmod comp name ext */
|
||||
T("[test.module]", true , true , true, false, "[test.module]", NULL);
|
||||
T("[test.module]", false , true , true, false, NULL , NULL);
|
||||
T("[test.module]", true , false , true, false, "[test.module]", NULL);
|
||||
T("[test.module]", false , false , true, false, NULL , NULL);
|
||||
M("[test.module]", PERF_RECORD_MISC_CPUMODE_UNKNOWN, true);
|
||||
M("[test.module]", PERF_RECORD_MISC_KERNEL, true);
|
||||
M("[test.module]", PERF_RECORD_MISC_USER, false);
|
||||
|
||||
/* path alloc_name alloc_ext kmod comp name ext */
|
||||
T("[vdso]", true , true , false, false, "[vdso]", NULL);
|
||||
T("[vdso]", false , true , false, false, NULL , NULL);
|
||||
T("[vdso]", true , false , false, false, "[vdso]", NULL);
|
||||
T("[vdso]", false , false , false, false, NULL , NULL);
|
||||
M("[vdso]", PERF_RECORD_MISC_CPUMODE_UNKNOWN, false);
|
||||
M("[vdso]", PERF_RECORD_MISC_KERNEL, false);
|
||||
M("[vdso]", PERF_RECORD_MISC_USER, false);
|
||||
|
||||
/* path alloc_name alloc_ext kmod comp name ext */
|
||||
T("[vsyscall]", true , true , false, false, "[vsyscall]", NULL);
|
||||
T("[vsyscall]", false , true , false, false, NULL , NULL);
|
||||
T("[vsyscall]", true , false , false, false, "[vsyscall]", NULL);
|
||||
T("[vsyscall]", false , false , false, false, NULL , NULL);
|
||||
M("[vsyscall]", PERF_RECORD_MISC_CPUMODE_UNKNOWN, false);
|
||||
M("[vsyscall]", PERF_RECORD_MISC_KERNEL, false);
|
||||
M("[vsyscall]", PERF_RECORD_MISC_USER, false);
|
||||
|
||||
/* path alloc_name alloc_ext kmod comp name ext */
|
||||
T("[kernel.kallsyms]", true , true , false, false, "[kernel.kallsyms]", NULL);
|
||||
T("[kernel.kallsyms]", false , true , false, false, NULL , NULL);
|
||||
T("[kernel.kallsyms]", true , false , false, false, "[kernel.kallsyms]", NULL);
|
||||
T("[kernel.kallsyms]", false , false , false, false, NULL , NULL);
|
||||
M("[kernel.kallsyms]", PERF_RECORD_MISC_CPUMODE_UNKNOWN, false);
|
||||
M("[kernel.kallsyms]", PERF_RECORD_MISC_KERNEL, false);
|
||||
M("[kernel.kallsyms]", PERF_RECORD_MISC_USER, false);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
|
|
|||
|
|
@ -166,12 +166,28 @@ bool is_supported_compression(const char *ext)
|
|||
return false;
|
||||
}
|
||||
|
||||
bool is_kernel_module(const char *pathname)
|
||||
bool is_kernel_module(const char *pathname, int cpumode)
|
||||
{
|
||||
struct kmod_path m;
|
||||
int mode = cpumode & PERF_RECORD_MISC_CPUMODE_MASK;
|
||||
|
||||
if (kmod_path__parse(&m, pathname))
|
||||
return NULL;
|
||||
WARN_ONCE(mode != cpumode,
|
||||
"Internal error: passing unmasked cpumode (%x) to is_kernel_module",
|
||||
cpumode);
|
||||
|
||||
switch (mode) {
|
||||
case PERF_RECORD_MISC_USER:
|
||||
case PERF_RECORD_MISC_HYPERVISOR:
|
||||
case PERF_RECORD_MISC_GUEST_USER:
|
||||
return false;
|
||||
/* Treat PERF_RECORD_MISC_CPUMODE_UNKNOWN as kernel */
|
||||
default:
|
||||
if (kmod_path__parse(&m, pathname)) {
|
||||
pr_err("Failed to check whether %s is a kernel module or not. Assume it is.",
|
||||
pathname);
|
||||
return true;
|
||||
}
|
||||
}
|
||||
|
||||
return m.kmod;
|
||||
}
|
||||
|
|
@ -215,12 +231,33 @@ int __kmod_path__parse(struct kmod_path *m, const char *path,
|
|||
{
|
||||
const char *name = strrchr(path, '/');
|
||||
const char *ext = strrchr(path, '.');
|
||||
bool is_simple_name = false;
|
||||
|
||||
memset(m, 0x0, sizeof(*m));
|
||||
name = name ? name + 1 : path;
|
||||
|
||||
/*
|
||||
* '.' is also a valid character for module name. For example:
|
||||
* [aaa.bbb] is a valid module name. '[' should have higher
|
||||
* priority than '.ko' suffix.
|
||||
*
|
||||
* The kernel names are from machine__mmap_name. Such
|
||||
* name should belong to kernel itself, not kernel module.
|
||||
*/
|
||||
if (name[0] == '[') {
|
||||
is_simple_name = true;
|
||||
if ((strncmp(name, "[kernel.kallsyms]", 17) == 0) ||
|
||||
(strncmp(name, "[guest.kernel.kallsyms", 22) == 0) ||
|
||||
(strncmp(name, "[vdso]", 6) == 0) ||
|
||||
(strncmp(name, "[vsyscall]", 10) == 0)) {
|
||||
m->kmod = false;
|
||||
|
||||
} else
|
||||
m->kmod = true;
|
||||
}
|
||||
|
||||
/* No extension, just return name. */
|
||||
if (ext == NULL) {
|
||||
if ((ext == NULL) || is_simple_name) {
|
||||
if (alloc_name) {
|
||||
m->name = strdup(name);
|
||||
return m->name ? 0 : -ENOMEM;
|
||||
|
|
|
|||
|
|
@ -220,7 +220,7 @@ char dso__symtab_origin(const struct dso *dso);
|
|||
int dso__read_binary_type_filename(const struct dso *dso, enum dso_binary_type type,
|
||||
char *root_dir, char *filename, size_t size);
|
||||
bool is_supported_compression(const char *ext);
|
||||
bool is_kernel_module(const char *pathname);
|
||||
bool is_kernel_module(const char *pathname, int cpumode);
|
||||
bool decompress_to_file(const char *ext, const char *filename, int output_fd);
|
||||
bool dso__needs_decompress(struct dso *dso);
|
||||
|
||||
|
|
|
|||
|
|
@ -1239,7 +1239,7 @@ static int __event_process_build_id(struct build_id_event *bev,
|
|||
{
|
||||
int err = -1;
|
||||
struct machine *machine;
|
||||
u16 misc;
|
||||
u16 cpumode;
|
||||
struct dso *dso;
|
||||
enum dso_kernel_type dso_type;
|
||||
|
||||
|
|
@ -1247,9 +1247,9 @@ static int __event_process_build_id(struct build_id_event *bev,
|
|||
if (!machine)
|
||||
goto out;
|
||||
|
||||
misc = bev->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
|
||||
cpumode = bev->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
|
||||
|
||||
switch (misc) {
|
||||
switch (cpumode) {
|
||||
case PERF_RECORD_MISC_KERNEL:
|
||||
dso_type = DSO_TYPE_KERNEL;
|
||||
break;
|
||||
|
|
@ -1270,7 +1270,7 @@ static int __event_process_build_id(struct build_id_event *bev,
|
|||
|
||||
dso__set_build_id(dso, &bev->build_id);
|
||||
|
||||
if (!is_kernel_module(filename))
|
||||
if (!is_kernel_module(filename, cpumode))
|
||||
dso->kernel = dso_type;
|
||||
|
||||
build_id__sprintf(dso->build_id, sizeof(dso->build_id),
|
||||
|
|
|
|||
|
|
@ -1149,9 +1149,29 @@ static int machine__process_kernel_mmap_event(struct machine *machine,
|
|||
struct dso *dso;
|
||||
|
||||
list_for_each_entry(dso, &machine->dsos.head, node) {
|
||||
if (!dso->kernel || is_kernel_module(dso->long_name))
|
||||
|
||||
/*
|
||||
* The cpumode passed to is_kernel_module is not the
|
||||
* cpumode of *this* event. If we insist on passing
|
||||
* correct cpumode to is_kernel_module, we should
|
||||
* record the cpumode when we adding this dso to the
|
||||
* linked list.
|
||||
*
|
||||
* However we don't really need passing correct
|
||||
* cpumode. We know the correct cpumode must be kernel
|
||||
* mode (if not, we should not link it onto kernel_dsos
|
||||
* list).
|
||||
*
|
||||
* Therefore, we pass PERF_RECORD_MISC_CPUMODE_UNKNOWN.
|
||||
* is_kernel_module() treats it as a kernel cpumode.
|
||||
*/
|
||||
|
||||
if (!dso->kernel ||
|
||||
is_kernel_module(dso->long_name,
|
||||
PERF_RECORD_MISC_CPUMODE_UNKNOWN))
|
||||
continue;
|
||||
|
||||
|
||||
kernel = dso;
|
||||
break;
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in New Issue