diff options
| -rw-r--r-- | arch/Kconfig | 2 | ||||
| -rw-r--r-- | kernel/kprobes.c | 14 |
2 files changed, 9 insertions, 7 deletions
diff --git a/arch/Kconfig b/arch/Kconfig index 1aafb4efbb51..f75c8e8a229b 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -90,7 +90,7 @@ config STATIC_KEYS_SELFTEST config OPTPROBES def_bool y depends on KPROBES && HAVE_OPTPROBES - depends on !PREEMPT + select TASKS_RCU if PREEMPT config KPROBES_ON_FTRACE def_bool y diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 15fba7fe57c8..a8fc1492b308 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -573,13 +573,15 @@ static void kprobe_optimizer(struct work_struct *work) do_unoptimize_kprobes(); /* - * Step 2: Wait for quiesence period to ensure all running interrupts - * are done. Because optprobe may modify multiple instructions - * there is a chance that Nth instruction is interrupted. In that - * case, running interrupt can return to 2nd-Nth byte of jump - * instruction. This wait is for avoiding it. + * Step 2: Wait for quiesence period to ensure all potentially + * preempted tasks to have normally scheduled. Because optprobe + * may modify multiple instructions, there is a chance that Nth + * instruction is preempted. In that case, such tasks can return + * to 2nd-Nth byte of jump instruction. This wait is for avoiding it. + * Note that on non-preemptive kernel, this is transparently converted + * to synchronoze_sched() to wait for all interrupts to have completed. */ - synchronize_sched(); + synchronize_rcu_tasks(); /* Step 3: Optimize kprobes after quiesence period */ do_optimize_kprobes(); |