powerpc/fsl-booke: Fix problem with _tlbil_va being interrupted

An example calling sequence which we did see:

copy_user_highpage -> kmap_atomic -> flush_tlb_page -> _tlbil_va

We got interrupted after setting up the MAS registers before the
tlbwe and the interrupt handler that caused the interrupt also did
a kmap_atomic (ide code) and thus on returning from the interrupt
the MAS registers no longer contained the proper values.

Since we dont save/restore MAS registers for normal interrupts we
need to disable interrupts in _tlbil_va to ensure atomicity.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S
index bdc8b0e860e5..d108715129e2 100644
--- a/arch/powerpc/kernel/misc_32.S
+++ b/arch/powerpc/kernel/misc_32.S
@@ -479,6 +479,8 @@ _GLOBAL(_tlbil_pid)
  * (no broadcast)
  */
 _GLOBAL(_tlbil_va)
+        mfmsr   r10
+        wrteei  0
         slwi    r4,r4,16
         mtspr   SPRN_MAS6,r4            /* assume AS=0 for now */
         tlbsx   0,r3
@@ -490,6 +492,7 @@ _GLOBAL(_tlbil_va)
         tlbwe
         msync
         isync
+        wrtee   r10
         blr
 #endif /* CONFIG_FSL_BOOKE */