diff options
Diffstat (limited to 'arch/ppc64')
| -rw-r--r-- | arch/ppc64/kernel/kprobes.c | 24 |
1 files changed, 6 insertions, 18 deletions
diff --git a/arch/ppc64/kernel/kprobes.c b/arch/ppc64/kernel/kprobes.c index 3f89f3e..e0a25b3 100644 --- a/arch/ppc64/kernel/kprobes.c +++ b/arch/ppc64/kernel/kprobes.c @@ -30,7 +30,6 @@ #include <linux/config.h> #include <linux/kprobes.h> #include <linux/ptrace.h> -#include <linux/spinlock.h> #include <linux/preempt.h> #include <asm/cacheflush.h> #include <asm/kdebug.h> @@ -125,6 +124,7 @@ static inline void set_current_kprobe(struct kprobe *p, struct pt_regs *regs, kcb->kprobe_saved_msr = regs->msr; } +/* Called with kretprobe_lock held */ void __kprobes arch_prepare_kretprobe(struct kretprobe *rp, struct pt_regs *regs) { @@ -152,8 +152,6 @@ static inline int kprobe_handler(struct pt_regs *regs) /* Check we're not actually recursing */ if (kprobe_running()) { - /* We *are* holding lock here, so this is safe. - Disarm the probe we just hit, and ignore it. */ p = get_kprobe(addr); if (p) { kprobe_opcode_t insn = *p->ainsn.insn; @@ -161,7 +159,6 @@ static inline int kprobe_handler(struct pt_regs *regs) is_trap(insn)) { regs->msr &= ~MSR_SE; regs->msr |= kcb->kprobe_saved_msr; - unlock_kprobes(); goto no_kprobe; } /* We have reentered the kprobe_handler(), since @@ -183,14 +180,11 @@ static inline int kprobe_handler(struct pt_regs *regs) goto ss_probe; } } - /* If it's not ours, can't be delete race, (we hold lock). */ goto no_kprobe; } - lock_kprobes(); p = get_kprobe(addr); if (!p) { - unlock_kprobes(); if (*addr != BREAKPOINT_INSTRUCTION) { /* * PowerPC has multiple variants of the "trap" @@ -254,9 +248,10 @@ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs) struct kretprobe_instance *ri = NULL; struct hlist_head *head; struct hlist_node *node, *tmp; - unsigned long orig_ret_address = 0; + unsigned long flags, orig_ret_address = 0; unsigned long trampoline_address =(unsigned long)&kretprobe_trampoline; + spin_lock_irqsave(&kretprobe_lock, flags); head = kretprobe_inst_table_head(current); /* @@ -296,7 +291,7 @@ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs) regs->nip = orig_ret_address; reset_current_kprobe(); - unlock_kprobes(); + spin_unlock_irqrestore(&kretprobe_lock, flags); preempt_enable_no_resched(); /* @@ -348,7 +343,6 @@ static inline int post_kprobe_handler(struct pt_regs *regs) goto out; } reset_current_kprobe(); - unlock_kprobes(); out: preempt_enable_no_resched(); @@ -363,7 +357,6 @@ out: return 1; } -/* Interrupts disabled, kprobe_lock held. */ static inline int kprobe_fault_handler(struct pt_regs *regs, int trapnr) { struct kprobe *cur = kprobe_running(); @@ -378,7 +371,6 @@ static inline int kprobe_fault_handler(struct pt_regs *regs, int trapnr) regs->msr |= kcb->kprobe_saved_msr; reset_current_kprobe(); - unlock_kprobes(); preempt_enable_no_resched(); } return 0; @@ -393,11 +385,7 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self, struct die_args *args = (struct die_args *)data; int ret = NOTIFY_DONE; - /* - * Interrupts are not disabled here. We need to disable - * preemption, because kprobe_running() uses smp_processor_id(). - */ - preempt_disable(); + rcu_read_lock(); switch (val) { case DIE_BPT: if (kprobe_handler(args->regs)) @@ -415,7 +403,7 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self, default: break; } - preempt_enable_no_resched(); + rcu_read_unlock(); return ret; } |