arch/tile: don't enable irqs unconditionally in page fault handler

If we took a page fault while we had interrupts disabled, we
shouldn't enable them in the page fault handler.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

diff --git a/arch/tile/mm/fault.c b/arch/tile/mm/fault.c
index a1da473..22e58f5 100644 (file)
--- a/arch/tile/mm/fault.c
+++ b/arch/tile/mm/fault.c
@@ -342,9 +342,12 @@ static int handle_page_fault(struct pt_regs *regs,
        /*
         * If we're trying to touch user-space addresses, we must
         * be either at PL0, or else with interrupts enabled in the
-        * kernel, so either way we can re-enable interrupts here.
+        * kernel, so either way we can re-enable interrupts here
+        * unless we are doing atomic access to user space with
+        * interrupts disabled.
         */
-       local_irq_enable();
+       if (!(regs->flags & PT_FLAGS_DISABLE_IRQ))
+               local_irq_enable();
 
        mm = tsk->mm;