1 files changed, 16 insertions, 32 deletions

diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c
index e785cc9e1ecd..fce05a38851c 100644
--- a/arch/powerpc/kernel/kprobes.c
+++ b/arch/powerpc/kernel/kprobes.c
@@ -35,7 +35,7 @@
 #include <asm/code-patching.h>
 #include <asm/cacheflush.h>
 #include <asm/sstep.h>
-#include <asm/uaccess.h>
+#include <linux/uaccess.h>
 
 DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
 DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
@@ -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
@@ -282,6 +285,7 @@ asm(".global kretprobe_trampoline\n"
 	".type kretprobe_trampoline, @function\n"
 	"kretprobe_trampoline:\n"
 	"nop\n"
+	"blr\n"
 	".size kretprobe_trampoline, .-kretprobe_trampoline\n");
 
 /*
@@ -334,6 +338,13 @@ static int __kprobes trampoline_probe_handler(struct kprobe *p,
 
 	kretprobe_assert(ri, orig_ret_address, trampoline_address);
 	regs->nip = orig_ret_address;
+	/*
+	 * Make LR point to the orig_ret_address.
+	 * When the 'nop' inside the kretprobe_trampoline
+	 * is optimized, we can do a 'blr' after executing the
+	 * detour buffer code.
+	 */
+	regs->link = orig_ret_address;
 
 	reset_current_kprobe();
 	kretprobe_hash_unlock(current, &flags);
@@ -359,12 +370,12 @@ 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 */
@@ -449,7 +460,7 @@ int __kprobes kprobe_fault_handler(struct pt_regs *regs, int trapnr)
 		 * zero, try to fix up.
 		 */
 		if ((entry = search_exception_tables(regs->nip)) != NULL) {
-			regs->nip = entry->fixup;
+			regs->nip = extable_fixup(entry);
 			return 1;
 		}
 
@@ -464,33 +475,6 @@ int __kprobes kprobe_fault_handler(struct pt_regs *regs, int trapnr)
 	return 0;
 }
 
-/*
- * Wrapper routine to for handling exceptions.
- */
-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;
-}
-
 unsigned long arch_deref_entry_point(void *entry)
 {
 	return ppc_global_function_entry(entry);