x86: do_page_fault small unification

Copy the prefetch of map_sem from X86_64 and move the check
notify_page_fault (soon to be kprobe_handle_fault) out of
the unlikely if() statement.

This makes the X86_32|64 pagefault handlers closer to each
other.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 2 insertions, 5 deletions

diff --git a/arch/x86/mm/fault_64.c b/arch/x86/mm/fault_64.c
index 80f8436ac8b2..c6b3ad515cf1 100644
--- a/arch/x86/mm/fault_64.c
+++ b/arch/x86/mm/fault_64.c
@@ -355,6 +355,8 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
 
         si_code = SEGV_MAPERR;
 
+        if (notify_page_fault(regs))
+                return;
 
         /*
          * We fault-in kernel-space virtual memory on-demand. The
@@ -380,8 +382,6 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
                         if (vmalloc_fault(address) >= 0)
                                 return;
                 }
-                if (notify_page_fault(regs))
-                        return;
                 /*
                  * Don't take the mm semaphore here. If we fixup a prefetch
                  * fault we could otherwise deadlock.
@@ -389,9 +389,6 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
                 goto bad_area_nosemaphore;
         }
 
-        if (notify_page_fault(regs))
-                return;
-
         if (likely(regs->flags & X86_EFLAGS_IF))
                 local_irq_enable();