diff options
Diffstat (limited to 'arch/ppc64/kernel/kprobes.c')
| -rw-r--r-- | arch/ppc64/kernel/kprobes.c | 26 |
1 files changed, 22 insertions, 4 deletions
diff --git a/arch/ppc64/kernel/kprobes.c b/arch/ppc64/kernel/kprobes.c index 782ce3efa2c..86cc5496db9 100644 --- a/arch/ppc64/kernel/kprobes.c +++ b/arch/ppc64/kernel/kprobes.c @@ -36,6 +36,8 @@ #include <asm/kdebug.h> #include <asm/sstep.h> +static DECLARE_MUTEX(kprobe_mutex); + static struct kprobe *current_kprobe; static unsigned long kprobe_status, kprobe_saved_msr; static struct kprobe *kprobe_prev; @@ -54,6 +56,15 @@ int arch_prepare_kprobe(struct kprobe *p) printk("Cannot register a kprobe on rfid or mtmsrd\n"); ret = -EINVAL; } + + /* insn must be on a special executable page on ppc64 */ + if (!ret) { + up(&kprobe_mutex); + p->ainsn.insn = get_insn_slot(); + down(&kprobe_mutex); + if (!p->ainsn.insn) + ret = -ENOMEM; + } return ret; } @@ -79,16 +90,22 @@ void arch_disarm_kprobe(struct kprobe *p) void arch_remove_kprobe(struct kprobe *p) { + up(&kprobe_mutex); + free_insn_slot(p->ainsn.insn); + down(&kprobe_mutex); } static inline void prepare_singlestep(struct kprobe *p, struct pt_regs *regs) { + kprobe_opcode_t insn = *p->ainsn.insn; + regs->msr |= MSR_SE; - /*single step inline if it a breakpoint instruction*/ - if (p->opcode == BREAKPOINT_INSTRUCTION) + + /* single step inline if it is a trap variant */ + if (IS_TW(insn) || IS_TD(insn) || IS_TWI(insn) || IS_TDI(insn)) regs->nip = (unsigned long)p->addr; else - regs->nip = (unsigned long)&p->ainsn.insn; + regs->nip = (unsigned long)p->ainsn.insn; } static inline void save_previous_kprobe(void) @@ -205,9 +222,10 @@ no_kprobe: static void resume_execution(struct kprobe *p, struct pt_regs *regs) { int ret; + unsigned int insn = *p->ainsn.insn; regs->nip = (unsigned long)p->addr; - ret = emulate_step(regs, p->ainsn.insn[0]); + ret = emulate_step(regs, insn); if (ret == 0) regs->nip = (unsigned long)p->addr + 4; } |