diff options
| author | Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> | 2016-11-21 20:06:41 +0300 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2016-11-23 14:56:25 +0300 |
| commit | 6cc89bad60a673a24386f1ada83de8a068a78909 (patch) | |
| tree | 5b116e7cce37b33103cc12d054ff8f382ca05fd0 /arch/powerpc/kernel/kprobes.c | |
| parent | 82de5797a26087c651a06de327e6aa9ea69d5d7f (diff) | |
| download | linux-6cc89bad60a673a24386f1ada83de8a068a78909.tar.xz | |
powerpc/kprobes: Invoke handlers directly
Invoke the kprobe handlers directly rather than through notify_die(), to
reduce path taken for handling kprobes. Similar to commit 6f6343f53d13
("kprobes/x86: Call exception handlers directly from do_int3/do_debug").
While at it, rename post_kprobe_handler() to kprobe_post_handler() for
more uniform naming.
Reported-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/kernel/kprobes.c')
| -rw-r--r-- | arch/powerpc/kernel/kprobes.c | 29 |
1 files changed, 7 insertions, 22 deletions
diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c index 9479d8e360cf..ad108b842669 100644 --- a/arch/powerpc/kernel/kprobes.c +++ b/arch/powerpc/kernel/kprobes.c @@ -140,13 +140,16 @@ void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, regs->link = (unsigned long)kretprobe_trampoline; } -static int __kprobes kprobe_handler(struct pt_regs *regs) +int __kprobes kprobe_handler(struct pt_regs *regs) { struct kprobe *p; int ret = 0; unsigned int *addr = (unsigned int *)regs->nip; struct kprobe_ctlblk *kcb; + if (user_mode(regs)) + return 0; + /* * We don't want to be preempted for the entire * duration of kprobe processing @@ -359,12 +362,12 @@ static int __kprobes trampoline_probe_handler(struct kprobe *p, * single-stepped a copy of the instruction. The address of this * copy is p->ainsn.insn. */ -static int __kprobes post_kprobe_handler(struct pt_regs *regs) +int __kprobes kprobe_post_handler(struct pt_regs *regs) { struct kprobe *cur = kprobe_running(); struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); - if (!cur) + if (!cur || user_mode(regs)) return 0; /* make sure we got here for instruction we have a kprobe on */ @@ -470,25 +473,7 @@ int __kprobes kprobe_fault_handler(struct pt_regs *regs, int trapnr) int __kprobes kprobe_exceptions_notify(struct notifier_block *self, unsigned long val, void *data) { - struct die_args *args = (struct die_args *)data; - int ret = NOTIFY_DONE; - - if (args->regs && user_mode(args->regs)) - return ret; - - switch (val) { - case DIE_BPT: - if (kprobe_handler(args->regs)) - ret = NOTIFY_STOP; - break; - case DIE_SSTEP: - if (post_kprobe_handler(args->regs)) - ret = NOTIFY_STOP; - break; - default: - break; - } - return ret; + return NOTIFY_DONE; } unsigned long arch_deref_entry_point(void *entry) |