[SPARC64] mm: don't re-evaluate *ptep

sparc64 prom_callback and new_setup_frame32 each operates on a user page
table without holding lock, and no doubt they've good reason.  But I'd
feel more confident if they were to do a "pte = *ptep" and then operate
on pte, rather than re-evaluating *ptep.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 2 deletions

diff --git a/arch/sparc64/kernel/signal32.c b/arch/sparc64/kernel/signal32.c
index aecccd0df1d1..009a86e5ded4 100644
--- a/arch/sparc64/kernel/signal32.c
+++ b/arch/sparc64/kernel/signal32.c
@@ -863,6 +863,7 @@ static void new_setup_frame32(struct k_sigaction *ka, struct pt_regs *regs,
                 pud_t *pudp = pud_offset(pgdp, address);
                 pmd_t *pmdp = pmd_offset(pudp, address);
                 pte_t *ptep;
+                pte_t pte;
 
                 regs->u_regs[UREG_I7] = (unsigned long) (&(sf->insns[0]) - 2);
         
@@ -873,9 +874,10 @@ static void new_setup_frame32(struct k_sigaction *ka, struct pt_regs *regs,
 
                 preempt_disable();
                 ptep = pte_offset_map(pmdp, address);
-                if (pte_present(*ptep)) {
+                pte = *ptep;
+                if (pte_present(pte)) {
                         unsigned long page = (unsigned long)
-                                page_address(pte_page(*ptep));
+                                page_address(pte_page(pte));
 
                         wmb();
                         __asm__ __volatile__("flush     %0 + %1"