parisc: optimize variable initialization in do_page_fault

The attached change defers the initialization of the variables tsk, mm
and flags until they are needed. As a result, the code won't crash if a
kernel probe is done with a corrupt context and the code will be better
optimized.

Signed-off-by: John David Anglin  <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>

1 files changed, 10 insertions, 5 deletions

diff --git a/arch/parisc/mm/fault.c b/arch/parisc/mm/fault.c
index 00c0ed333a3d..0293588d5b8c 100644
--- a/arch/parisc/mm/fault.c
+++ b/arch/parisc/mm/fault.c
@@ -171,20 +171,25 @@ void do_page_fault(struct pt_regs *regs, unsigned long code,
                               unsigned long address)
 {
         struct vm_area_struct *vma, *prev_vma;
-        struct task_struct *tsk = current;
-        struct mm_struct *mm = tsk->mm;
+        struct task_struct *tsk;
+        struct mm_struct *mm;
         unsigned long acc_type;
         int fault;
-        unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+        unsigned int flags;
 
-        if (in_atomic() || !mm)
+        if (in_atomic())
                 goto no_context;
 
+        tsk = current;
+        mm = tsk->mm;
+        if (!mm)
+                goto no_context;
+
+        flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
         if (user_mode(regs))
                 flags |= FAULT_FLAG_USER;
 
         acc_type = parisc_acctyp(code, regs->iir);
-
         if (acc_type & VM_WRITE)
                 flags |= FAULT_FLAG_WRITE;
 retry: