diff options
| -rw-r--r-- | Documentation/kprobes.txt | 8 | ||||
| -rw-r--r-- | arch/arm/kernel/perf_event.c | 2 | ||||
| -rw-r--r-- | arch/x86/Kconfig | 5 | ||||
| -rw-r--r-- | arch/x86/kernel/alternative.c | 3 | ||||
| -rw-r--r-- | include/linux/stop_machine.h | 10 | ||||
| -rw-r--r-- | kernel/test_kprobes.c | 12 |
6 files changed, 30 insertions, 10 deletions
diff --git a/Documentation/kprobes.txt b/Documentation/kprobes.txt index 1762b81fcdf..741fe66d6ec 100644 --- a/Documentation/kprobes.txt +++ b/Documentation/kprobes.txt @@ -542,9 +542,11 @@ Kprobes does not use mutexes or allocate memory except during registration and unregistration. Probe handlers are run with preemption disabled. Depending on the -architecture, handlers may also run with interrupts disabled. In any -case, your handler should not yield the CPU (e.g., by attempting to -acquire a semaphore). +architecture and optimization state, handlers may also run with +interrupts disabled (e.g., kretprobe handlers and optimized kprobe +handlers run without interrupt disabled on x86/x86-64). In any case, +your handler should not yield the CPU (e.g., by attempting to acquire +a semaphore). Since a return probe is implemented by replacing the return address with the trampoline's address, stack backtraces and calls diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c index ad19c276b10..55addc85eaa 100644 --- a/arch/arm/kernel/perf_event.c +++ b/arch/arm/kernel/perf_event.c @@ -534,7 +534,7 @@ static int armpmu_event_init(struct perf_event *event) event->destroy = hw_perf_event_destroy; if (!atomic_inc_not_zero(&active_events)) { - if (atomic_read(&active_events) > armpmu.num_events) { + if (atomic_read(&active_events) > armpmu->num_events) { atomic_dec(&active_events); return -ENOSPC; } diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index b431a0824a9..c14d8b4d2f7 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -60,6 +60,7 @@ config X86 select HAVE_ARCH_KMEMCHECK select HAVE_USER_RETURN_NOTIFIER select HAVE_ARCH_JUMP_LABEL + select HAVE_TEXT_POKE_SMP config INSTRUCTION_DECODER def_bool (KPROBES || PERF_EVENTS) @@ -2126,6 +2127,10 @@ config HAVE_ATOMIC_IOMAP def_bool y depends on X86_32 +config HAVE_TEXT_POKE_SMP + bool + select STOP_MACHINE if SMP + source "net/Kconfig" source "drivers/Kconfig" diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index cb0e6d385f6..a36bb90aef5 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -637,7 +637,8 @@ void *__kprobes text_poke_smp(void *addr, const void *opcode, size_t len) tpp.len = len; atomic_set(&stop_machine_first, 1); wrote_text = 0; - stop_machine(stop_machine_text_poke, (void *)&tpp, NULL); + /* Use __stop_machine() because the caller already got online_cpus. */ + __stop_machine(stop_machine_text_poke, (void *)&tpp, NULL); return addr; } diff --git a/include/linux/stop_machine.h b/include/linux/stop_machine.h index 6b524a0d02e..1808960c505 100644 --- a/include/linux/stop_machine.h +++ b/include/linux/stop_machine.h @@ -126,8 +126,8 @@ int __stop_machine(int (*fn)(void *), void *data, const struct cpumask *cpus); #else /* CONFIG_STOP_MACHINE && CONFIG_SMP */ -static inline int stop_machine(int (*fn)(void *), void *data, - const struct cpumask *cpus) +static inline int __stop_machine(int (*fn)(void *), void *data, + const struct cpumask *cpus) { int ret; local_irq_disable(); @@ -136,5 +136,11 @@ static inline int stop_machine(int (*fn)(void *), void *data, return ret; } +static inline int stop_machine(int (*fn)(void *), void *data, + const struct cpumask *cpus) +{ + return __stop_machine(fn, data, cpus); +} + #endif /* CONFIG_STOP_MACHINE && CONFIG_SMP */ #endif /* _LINUX_STOP_MACHINE */ diff --git a/kernel/test_kprobes.c b/kernel/test_kprobes.c index 4f104515a19..f8b11a28317 100644 --- a/kernel/test_kprobes.c +++ b/kernel/test_kprobes.c @@ -115,7 +115,9 @@ static int test_kprobes(void) int ret; struct kprobe *kps[2] = {&kp, &kp2}; - kp.addr = 0; /* addr should be cleard for reusing kprobe. */ + /* addr and flags should be cleard for reusing kprobe. */ + kp.addr = NULL; + kp.flags = 0; ret = register_kprobes(kps, 2); if (ret < 0) { printk(KERN_ERR "Kprobe smoke test failed: " @@ -210,7 +212,9 @@ static int test_jprobes(void) int ret; struct jprobe *jps[2] = {&jp, &jp2}; - jp.kp.addr = 0; /* addr should be cleard for reusing kprobe. */ + /* addr and flags should be cleard for reusing kprobe. */ + jp.kp.addr = NULL; + jp.kp.flags = 0; ret = register_jprobes(jps, 2); if (ret < 0) { printk(KERN_ERR "Kprobe smoke test failed: " @@ -323,7 +327,9 @@ static int test_kretprobes(void) int ret; struct kretprobe *rps[2] = {&rp, &rp2}; - rp.kp.addr = 0; /* addr should be cleard for reusing kprobe. */ + /* addr and flags should be cleard for reusing kprobe. */ + rp.kp.addr = NULL; + rp.kp.flags = 0; ret = register_kretprobes(rps, 2); if (ret < 0) { printk(KERN_ERR "Kprobe smoke test failed: " |