diff --git a/[refs] b/[refs]
index f27c7cab00a3..035e916ed82f 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 4bc32c4d5cde5c57edcc9c2fe5057da8a4dd0153
+refs/heads/master: a9ba9a3b3897561d01e04cd21433746df46548c0
diff --git a/trunk/arch/x86_64/mm/fault.c b/trunk/arch/x86_64/mm/fault.c
index de91e17daf6f..316c53de47bd 100644
--- a/trunk/arch/x86_64/mm/fault.c
+++ b/trunk/arch/x86_64/mm/fault.c
@@ -314,11 +314,13 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
 	unsigned long flags;
 	siginfo_t info;
 
+	tsk = current;
+	mm = tsk->mm;
+	prefetchw(&mm->mmap_sem);
+
 	/* get the address */
 	__asm__("movq %%cr2,%0":"=r" (address));
 
-	tsk = current;
-	mm = tsk->mm;
 	info.si_code = SEGV_MAPERR;