From e5e774d8833de1a0037be2384efccadf16935675 Mon Sep 17 00:00:00 2001
From: Kumar Gala <galak@kernel.crashing.org>
Date: Sat, 13 Dec 2008 17:01:37 -0600
Subject: [PATCH] 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>
---
 arch/powerpc/kernel/misc_32.S | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S
index bdc8b0e860e5e..d108715129e26 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 */
 
-- 
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