[SPARC64]: Optimize fault kprobe handling just like powerpc.

And eliminate DIE_GPF while we're at it.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 14 insertions, 31 deletions

diff --git a/arch/sparc64/mm/fault.c b/arch/sparc64/mm/fault.c
index c32e309f778..b582024d219 100644
--- a/arch/sparc64/mm/fault.c
+++ b/arch/sparc64/mm/fault.c
@@ -32,36 +32,23 @@
 #include <asm/mmu_context.h>
 
 #ifdef CONFIG_KPROBES
-ATOMIC_NOTIFIER_HEAD(notify_page_fault_chain);
-
-/* Hook to register for page fault notifications */
-int register_page_fault_notifier(struct notifier_block *nb)
+static inline int notify_page_fault(struct pt_regs *regs)
 {
-	return atomic_notifier_chain_register(&notify_page_fault_chain, nb);
-}
-
-int unregister_page_fault_notifier(struct notifier_block *nb)
-{
-	return atomic_notifier_chain_unregister(&notify_page_fault_chain, nb);
-}
-
-static inline int notify_page_fault(enum die_val val, const char *str,
-			struct pt_regs *regs, long err, int trap, int sig)
-{
-	struct die_args args = {
-		.regs = regs,
-		.str = str,
-		.err = err,
-		.trapnr = trap,
-		.signr = sig
-	};
-	return atomic_notifier_call_chain(&notify_page_fault_chain, val, &args);
+	int ret = 0;
+
+	/* kprobe_running() needs smp_processor_id() */
+	if (!user_mode(regs)) {
+		preempt_disable();
+		if (kprobe_running() && kprobe_fault_handler(regs, 0))
+			ret = 1;
+		preempt_enable();
+	}
+	return ret;
 }
 #else
-static inline int notify_page_fault(enum die_val val, const char *str,
-			struct pt_regs *regs, long err, int trap, int sig)
+static inline int notify_page_fault(struct pt_regs *regs)
 {
-	return NOTIFY_DONE;
+	return 0;
 }
 #endif
 
@@ -120,9 +107,6 @@ static void __kprobes unhandled_fault(unsigned long address,
 	printk(KERN_ALERT "tsk->{mm,active_mm}->pgd = %016lx\n",
 	       (tsk->mm ? (unsigned long) tsk->mm->pgd :
 		          (unsigned long) tsk->active_mm->pgd));
-	if (notify_die(DIE_GPF, "general protection fault", regs,
-		       0, 0, SIGSEGV) == NOTIFY_STOP)
-		return;
 	die_if_kernel("Oops", regs);
 }
 
@@ -299,8 +283,7 @@ asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs)
 
 	fault_code = get_thread_fault_code();
 
-	if (notify_page_fault(DIE_PAGE_FAULT, "page_fault", regs,
-		       fault_code, 0, SIGSEGV) == NOTIFY_STOP)
+	if (notify_page_fault(regs))
 		return;
 
 	si_code = SEGV_MAPERR;