Linus,
please pull the latest perf-urgent-for-linus git tree from:
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git
perf-urgent-for-linus
A couple of fixes for perf and kprobes:
- Add he missing exclude_kernel attribute for the precise_ip level so
!CAP_SYS_ADMIN users get the proper results.
- Warn instead of failing completely when perf has no unwind support for
a particular architectiure built in.
- Ensure that jprobes are at function entry and not at some random place.
Thanks,
tglx
------------------>
Arnaldo Carvalho de Melo (1):
perf evsel: Set attr.exclude_kernel when probing max attr.precise_ip
Jiri Olsa (1):
perf unwind: Do not fail due to missing unwind support
Naveen N. Rao (3):
kprobes: Rename [arch_]function_offset_within_entry() to
[arch_]kprobe_on_func_entry()
kprobes: Simplify register_jprobes()
kprobes: Ensure that jprobe probepoints are at function entry
arch/powerpc/kernel/kprobes.c | 2 +-
include/linux/kprobes.h | 4 ++--
kernel/kprobes.c | 42 ++++++++++++++++++++++----------------
kernel/trace/trace_kprobe.c | 2 +-
tools/perf/util/evsel.c | 1 +
tools/perf/util/unwind-libunwind.c | 2 +-
6 files changed, 30 insertions(+), 23 deletions(-)
diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c
index 01addfb0ed0a..586508e949f0 100644
--- a/arch/powerpc/kernel/kprobes.c
+++ b/arch/powerpc/kernel/kprobes.c
@@ -221,7 +221,7 @@ static nokprobe_inline void set_current_kprobe(struct
kprobe *p, struct pt_regs
kcb->kprobe_saved_msr = regs->msr;
}
-bool arch_function_offset_within_entry(unsigned long offset)
+bool arch_kprobe_on_func_entry(unsigned long offset)
{
#ifdef PPC64_ELF_ABI_v2
#ifdef CONFIG_KPROBES_ON_FTRACE
diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h
index 541df0b5b815..bd2684700b74 100644
--- a/include/linux/kprobes.h
+++ b/include/linux/kprobes.h
@@ -267,8 +267,8 @@ extern int arch_init_kprobes(void);
extern void show_registers(struct pt_regs *regs);
extern void kprobes_inc_nmissed_count(struct kprobe *p);
extern bool arch_within_kprobe_blacklist(unsigned long addr);
-extern bool arch_function_offset_within_entry(unsigned long offset);
-extern bool function_offset_within_entry(kprobe_opcode_t *addr, const char
*sym, unsigned long offset);
+extern bool arch_kprobe_on_func_entry(unsigned long offset);
+extern bool kprobe_on_func_entry(kprobe_opcode_t *addr, const char *sym,
unsigned long offset);
extern bool within_kprobe_blacklist(unsigned long addr);
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 6756d750b31b..a1606a4224e1 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -1771,24 +1771,13 @@ unsigned long __weak arch_deref_entry_point(void *entry)
int register_jprobes(struct jprobe **jps, int num)
{
- struct jprobe *jp;
int ret = 0, i;
if (num <= 0)
return -EINVAL;
+
for (i = 0; i < num; i++) {
- unsigned long addr, offset;
- jp = jps[i];
- addr = arch_deref_entry_point(jp->entry);
-
- /* Verify probepoint is a function entry point */
- if (kallsyms_lookup_size_offset(addr, NULL, &offset) &&
- offset == 0) {
- jp->kp.pre_handler = setjmp_pre_handler;
- jp->kp.break_handler = longjmp_break_handler;
- ret = register_kprobe(&jp->kp);
- } else
- ret = -EINVAL;
+ ret = register_jprobe(jps[i]);
if (ret < 0) {
if (i > 0)
@@ -1796,13 +1785,30 @@ int register_jprobes(struct jprobe **jps, int num)
break;
}
}
+
return ret;
}
EXPORT_SYMBOL_GPL(register_jprobes);
int register_jprobe(struct jprobe *jp)
{
- return register_jprobes(&jp, 1);
+ unsigned long addr, offset;
+ struct kprobe *kp = &jp->kp;
+
+ /*
+ * Verify probepoint as well as the jprobe handler are
+ * valid function entry points.
+ */
+ addr = arch_deref_entry_point(jp->entry);
+
+ if (kallsyms_lookup_size_offset(addr, NULL, &offset) && offset == 0 &&
+ kprobe_on_func_entry(kp->addr, kp->symbol_name, kp->offset)) {
+ kp->pre_handler = setjmp_pre_handler;
+ kp->break_handler = longjmp_break_handler;
+ return register_kprobe(kp);
+ }
+
+ return -EINVAL;
}
EXPORT_SYMBOL_GPL(register_jprobe);
@@ -1888,12 +1894,12 @@ static int pre_handler_kretprobe(struct kprobe *p,
struct pt_regs *regs)
}
NOKPROBE_SYMBOL(pre_handler_kretprobe);
-bool __weak arch_function_offset_within_entry(unsigned long offset)
+bool __weak arch_kprobe_on_func_entry(unsigned long offset)
{
return !offset;
}
-bool function_offset_within_entry(kprobe_opcode_t *addr, const char *sym,
unsigned long offset)
+bool kprobe_on_func_entry(kprobe_opcode_t *addr, const char *sym, unsigned
long offset)
{
kprobe_opcode_t *kp_addr = _kprobe_addr(addr, sym, offset);
@@ -1901,7 +1907,7 @@ bool function_offset_within_entry(kprobe_opcode_t *addr,
const char *sym, unsign
return false;
if (!kallsyms_lookup_size_offset((unsigned long)kp_addr, NULL, &offset)
||
-
!arch_function_offset_within_entry(offset))
+
!arch_kprobe_on_func_entry(offset))
return false;
return true;
@@ -1914,7 +1920,7 @@ int register_kretprobe(struct kretprobe *rp)
int i;
void *addr;
- if (!function_offset_within_entry(rp->kp.addr, rp->kp.symbol_name,
rp->kp.offset))
+ if (!kprobe_on_func_entry(rp->kp.addr, rp->kp.symbol_name,
rp->kp.offset))
return -EINVAL;
if (kretprobe_blacklist_size) {
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index b53c8d369163..2c5221819be5 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -720,7 +720,7 @@ static int create_trace_kprobe(int argc, char **argv)
return ret;
}
if (offset && is_return &&
- !function_offset_within_entry(NULL, symbol, offset)) {
+ !kprobe_on_func_entry(NULL, symbol, offset)) {
pr_info("Given offset is not valid for return
probe.\n");
return -EINVAL;
}
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 6f4882f8d61f..87b431886670 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -273,6 +273,7 @@ struct perf_evsel *perf_evsel__new_cycles(void)
struct perf_event_attr attr = {
.type = PERF_TYPE_HARDWARE,
.config = PERF_COUNT_HW_CPU_CYCLES,
+ .exclude_kernel = 1,
};
struct perf_evsel *evsel;
diff --git a/tools/perf/util/unwind-libunwind.c
b/tools/perf/util/unwind-libunwind.c
index 6d542a4e0648..8aef572d0889 100644
--- a/tools/perf/util/unwind-libunwind.c
+++ b/tools/perf/util/unwind-libunwind.c
@@ -50,7 +50,7 @@ int unwind__prepare_access(struct thread *thread, struct map
*map,
if (!ops) {
pr_err("unwind: target platform=%s is not supported\n", arch);
- return -1;
+ return 0;
}
out_register:
unwind__register_ops(thread, ops);
