Home Home > GIT Browse
summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2015-03-01 11:56:13 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2015-03-01 11:56:13 -0800
commitd7b48fec3520da075a4093d3aa37ce4daff7510b (patch)
treee67cf00d4c3712e41b2e97e45507de0467b5c44d
parent2ea51b884b07ac7fbb49eb91860eb05c13161ad2 (diff)
parent021f5f12f2ab44874193c68fb19eea154493f83a (diff)
Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar: "Two kprobes fixes and a handful of tooling fixes" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf tools: Make sparc64 arch point to sparc perf symbols: Define EM_AARCH64 for older OSes perf top: Fix SIGBUS on sparc64 perf tools: Fix probing for PERF_FLAG_FD_CLOEXEC flag perf tools: Fix pthread_attr_setaffinity_np build error perf tools: Define _GNU_SOURCE on pthread_attr_setaffinity_np feature check perf bench: Fix order of arguments to memcpy_alloc_mem kprobes/x86: Check for invalid ftrace location in __recover_probed_insn() kprobes/x86: Use 5-byte NOP when the code might be modified by ftrace
-rw-r--r--arch/x86/kernel/kprobes/core.c54
-rw-r--r--arch/x86/kernel/kprobes/opt.c2
-rw-r--r--tools/perf/bench/mem-memcpy.c4
-rw-r--r--tools/perf/config/Makefile.arch4
-rw-r--r--tools/perf/config/feature-checks/Makefile2
-rw-r--r--tools/perf/config/feature-checks/test-pthread-attr-setaffinity-np.c3
-rw-r--r--tools/perf/util/cloexec.c18
-rw-r--r--tools/perf/util/evlist.h2
-rw-r--r--tools/perf/util/symbol-elf.c5
9 files changed, 72 insertions, 22 deletions
diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c
index 6a1146ea4d4d..4e3d5a9621fe 100644
--- a/arch/x86/kernel/kprobes/core.c
+++ b/arch/x86/kernel/kprobes/core.c
@@ -223,27 +223,48 @@ static unsigned long
__recover_probed_insn(kprobe_opcode_t *buf, unsigned long addr)
{
struct kprobe *kp;
+ unsigned long faddr;
kp = get_kprobe((void *)addr);
- /* There is no probe, return original address */
- if (!kp)
+ faddr = ftrace_location(addr);
+ /*
+ * Addresses inside the ftrace location are refused by
+ * arch_check_ftrace_location(). Something went terribly wrong
+ * if such an address is checked here.
+ */
+ if (WARN_ON(faddr && faddr != addr))
+ return 0UL;
+ /*
+ * Use the current code if it is not modified by Kprobe
+ * and it cannot be modified by ftrace.
+ */
+ if (!kp && !faddr)
return addr;
/*
- * Basically, kp->ainsn.insn has an original instruction.
- * However, RIP-relative instruction can not do single-stepping
- * at different place, __copy_instruction() tweaks the displacement of
- * that instruction. In that case, we can't recover the instruction
- * from the kp->ainsn.insn.
+ * Basically, kp->ainsn.insn has an original instruction.
+ * However, RIP-relative instruction can not do single-stepping
+ * at different place, __copy_instruction() tweaks the displacement of
+ * that instruction. In that case, we can't recover the instruction
+ * from the kp->ainsn.insn.
*
- * On the other hand, kp->opcode has a copy of the first byte of
- * the probed instruction, which is overwritten by int3. And
- * the instruction at kp->addr is not modified by kprobes except
- * for the first byte, we can recover the original instruction
- * from it and kp->opcode.
+ * On the other hand, in case on normal Kprobe, kp->opcode has a copy
+ * of the first byte of the probed instruction, which is overwritten
+ * by int3. And the instruction at kp->addr is not modified by kprobes
+ * except for the first byte, we can recover the original instruction
+ * from it and kp->opcode.
+ *
+ * In case of Kprobes using ftrace, we do not have a copy of
+ * the original instruction. In fact, the ftrace location might
+ * be modified at anytime and even could be in an inconsistent state.
+ * Fortunately, we know that the original code is the ideal 5-byte
+ * long NOP.
*/
- memcpy(buf, kp->addr, MAX_INSN_SIZE * sizeof(kprobe_opcode_t));
- buf[0] = kp->opcode;
+ memcpy(buf, (void *)addr, MAX_INSN_SIZE * sizeof(kprobe_opcode_t));
+ if (faddr)
+ memcpy(buf, ideal_nops[NOP_ATOMIC5], 5);
+ else
+ buf[0] = kp->opcode;
return (unsigned long)buf;
}
@@ -251,6 +272,7 @@ __recover_probed_insn(kprobe_opcode_t *buf, unsigned long addr)
* Recover the probed instruction at addr for further analysis.
* Caller must lock kprobes by kprobe_mutex, or disable preemption
* for preventing to release referencing kprobes.
+ * Returns zero if the instruction can not get recovered.
*/
unsigned long recover_probed_instruction(kprobe_opcode_t *buf, unsigned long addr)
{
@@ -285,6 +307,8 @@ static int can_probe(unsigned long paddr)
* normally used, we just go through if there is no kprobe.
*/
__addr = recover_probed_instruction(buf, addr);
+ if (!__addr)
+ return 0;
kernel_insn_init(&insn, (void *)__addr, MAX_INSN_SIZE);
insn_get_length(&insn);
@@ -333,6 +357,8 @@ int __copy_instruction(u8 *dest, u8 *src)
unsigned long recovered_insn =
recover_probed_instruction(buf, (unsigned long)src);
+ if (!recovered_insn)
+ return 0;
kernel_insn_init(&insn, (void *)recovered_insn, MAX_INSN_SIZE);
insn_get_length(&insn);
/* Another subsystem puts a breakpoint, failed to recover */
diff --git a/arch/x86/kernel/kprobes/opt.c b/arch/x86/kernel/kprobes/opt.c
index 0dd8d089c315..7b3b9d15c47a 100644
--- a/arch/x86/kernel/kprobes/opt.c
+++ b/arch/x86/kernel/kprobes/opt.c
@@ -259,6 +259,8 @@ static int can_optimize(unsigned long paddr)
*/
return 0;
recovered_insn = recover_probed_instruction(buf, addr);
+ if (!recovered_insn)
+ return 0;
kernel_insn_init(&insn, (void *)recovered_insn, MAX_INSN_SIZE);
insn_get_length(&insn);
/* Another subsystem puts a breakpoint */
diff --git a/tools/perf/bench/mem-memcpy.c b/tools/perf/bench/mem-memcpy.c
index 6c14afe8c1b1..db1d3a29d97f 100644
--- a/tools/perf/bench/mem-memcpy.c
+++ b/tools/perf/bench/mem-memcpy.c
@@ -289,7 +289,7 @@ static u64 do_memcpy_cycle(const struct routine *r, size_t len, bool prefault)
memcpy_t fn = r->fn.memcpy;
int i;
- memcpy_alloc_mem(&src, &dst, len);
+ memcpy_alloc_mem(&dst, &src, len);
if (prefault)
fn(dst, src, len);
@@ -312,7 +312,7 @@ static double do_memcpy_gettimeofday(const struct routine *r, size_t len,
void *src = NULL, *dst = NULL;
int i;
- memcpy_alloc_mem(&src, &dst, len);
+ memcpy_alloc_mem(&dst, &src, len);
if (prefault)
fn(dst, src, len);
diff --git a/tools/perf/config/Makefile.arch b/tools/perf/config/Makefile.arch
index ff95a68741d1..ac8721ffa6c8 100644
--- a/tools/perf/config/Makefile.arch
+++ b/tools/perf/config/Makefile.arch
@@ -21,6 +21,10 @@ ifeq ($(RAW_ARCH),x86_64)
endif
endif
+ifeq ($(RAW_ARCH),sparc64)
+ ARCH ?= sparc
+endif
+
ARCH ?= $(RAW_ARCH)
LP64 := $(shell echo __LP64__ | ${CC} ${CFLAGS} -E -x c - | tail -n 1)
diff --git a/tools/perf/config/feature-checks/Makefile b/tools/perf/config/feature-checks/Makefile
index 42ac05aaf8ac..b32ff3372514 100644
--- a/tools/perf/config/feature-checks/Makefile
+++ b/tools/perf/config/feature-checks/Makefile
@@ -49,7 +49,7 @@ test-hello.bin:
$(BUILD)
test-pthread-attr-setaffinity-np.bin:
- $(BUILD) -Werror -lpthread
+ $(BUILD) -D_GNU_SOURCE -Werror -lpthread
test-stackprotector-all.bin:
$(BUILD) -Werror -fstack-protector-all
diff --git a/tools/perf/config/feature-checks/test-pthread-attr-setaffinity-np.c b/tools/perf/config/feature-checks/test-pthread-attr-setaffinity-np.c
index 0a0d3ecb4e8a..2b81b72eca23 100644
--- a/tools/perf/config/feature-checks/test-pthread-attr-setaffinity-np.c
+++ b/tools/perf/config/feature-checks/test-pthread-attr-setaffinity-np.c
@@ -5,10 +5,11 @@ int main(void)
{
int ret = 0;
pthread_attr_t thread_attr;
+ cpu_set_t cs;
pthread_attr_init(&thread_attr);
/* don't care abt exact args, just the API itself in libpthread */
- ret = pthread_attr_setaffinity_np(&thread_attr, 0, NULL);
+ ret = pthread_attr_setaffinity_np(&thread_attr, sizeof(cs), &cs);
return ret;
}
diff --git a/tools/perf/util/cloexec.c b/tools/perf/util/cloexec.c
index 47b78b3f0325..6da965bdbc2c 100644
--- a/tools/perf/util/cloexec.c
+++ b/tools/perf/util/cloexec.c
@@ -25,6 +25,10 @@ static int perf_flag_probe(void)
if (cpu < 0)
cpu = 0;
+ /*
+ * Using -1 for the pid is a workaround to avoid gratuitous jump label
+ * changes.
+ */
while (1) {
/* check cloexec flag */
fd = sys_perf_event_open(&attr, pid, cpu, -1,
@@ -47,16 +51,24 @@ static int perf_flag_probe(void)
err, strerror_r(err, sbuf, sizeof(sbuf)));
/* not supported, confirm error related to PERF_FLAG_FD_CLOEXEC */
- fd = sys_perf_event_open(&attr, pid, cpu, -1, 0);
+ while (1) {
+ fd = sys_perf_event_open(&attr, pid, cpu, -1, 0);
+ if (fd < 0 && pid == -1 && errno == EACCES) {
+ pid = 0;
+ continue;
+ }
+ break;
+ }
err = errno;
+ if (fd >= 0)
+ close(fd);
+
if (WARN_ONCE(fd < 0 && err != EBUSY,
"perf_event_open(..., 0) failed unexpectedly with error %d (%s)\n",
err, strerror_r(err, sbuf, sizeof(sbuf))))
return -1;
- close(fd);
-
return 0;
}
diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h
index c94a9e03ecf1..e99a67632831 100644
--- a/tools/perf/util/evlist.h
+++ b/tools/perf/util/evlist.h
@@ -28,7 +28,7 @@ struct perf_mmap {
int mask;
int refcnt;
unsigned int prev;
- char event_copy[PERF_SAMPLE_MAX_SIZE];
+ char event_copy[PERF_SAMPLE_MAX_SIZE] __attribute__((aligned(8)));
};
struct perf_evlist {
diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c
index b24f9d8727a8..33b7a2aef713 100644
--- a/tools/perf/util/symbol-elf.c
+++ b/tools/perf/util/symbol-elf.c
@@ -11,6 +11,11 @@
#include <symbol/kallsyms.h>
#include "debug.h"
+#ifndef EM_AARCH64
+#define EM_AARCH64 183 /* ARM 64 bit */
+#endif
+
+
#ifdef HAVE_CPLUS_DEMANGLE_SUPPORT
extern char *cplus_demangle(const char *, int);