[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>

diff --git a/arch/sparc64/kernel/kprobes.c b/arch/sparc64/kernel/kprobes.c
index a44fe47..c93a15b 100644 (file)
--- a/arch/sparc64/kernel/kprobes.c
+++ b/arch/sparc64/kernel/kprobes.c
@@ -313,7 +313,7 @@ out:
        return 1;
 }
 
-static int __kprobes kprobe_fault_handler(struct pt_regs *regs, int trapnr)
+int __kprobes kprobe_fault_handler(struct pt_regs *regs, int trapnr)
 {
        struct kprobe *cur = kprobe_running();
        struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
@@ -403,15 +403,6 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
                if (post_kprobe_handler(args->regs))
                        ret = NOTIFY_STOP;
                break;
-       case DIE_GPF:
-       case DIE_PAGE_FAULT:
-               /* kprobe_running() needs smp_processor_id() */
-               preempt_disable();
-               if (kprobe_running() &&
-                   kprobe_fault_handler(args->regs, args->trapnr))
-                       ret = NOTIFY_STOP;
-               preempt_enable();
-               break;
        default:
                break;
        }

diff --git a/arch/sparc64/mm/fault.c b/arch/sparc64/mm/fault.c
index c32e309..b582024 100644 (file)
--- 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;

diff --git a/include/asm-sparc64/kdebug.h b/include/asm-sparc64/kdebug.h
index f8032e7..627e339 100644 (file)
--- a/include/asm-sparc64/kdebug.h
+++ b/include/asm-sparc64/kdebug.h
@@ -7,8 +7,19 @@
 
 struct pt_regs;
 
-extern int register_page_fault_notifier(struct notifier_block *);
-extern int unregister_page_fault_notifier(struct notifier_block *);
+/*
+ * These are only here because kprobes.c wants them to implement a
+ * blatant layering violation.  Will hopefully go away soon once all
+ * architectures are updated.
+ */
+static inline int register_page_fault_notifier(struct notifier_block *nb)
+{
+       return 0;
+}
+static inline int unregister_page_fault_notifier(struct notifier_block *nb)
+{
+       return 0;
+}
 
 extern void bad_trap(struct pt_regs *, long);
 
@@ -20,7 +31,6 @@ enum die_val {
        DIE_DIE,
        DIE_TRAP,
        DIE_TRAP_TL1,
-       DIE_GPF,
        DIE_CALL,
        DIE_PAGE_FAULT,
 };

diff --git a/include/asm-sparc64/kprobes.h b/include/asm-sparc64/kprobes.h
index becc38f..a331b7b 100644 (file)
--- a/include/asm-sparc64/kprobes.h
+++ b/include/asm-sparc64/kprobes.h
@@ -43,4 +43,5 @@ struct kprobe_ctlblk {
 
 extern int kprobe_exceptions_notify(struct notifier_block *self,
                                    unsigned long val, void *data);
+extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
 #endif /* _SPARC64_KPROBES_H */