3.16.48-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
commit 2952a6070e07ebdd5896f1f5b861acad677caded upstream.
Make sure we don't use a cached value of the KVM stage2 PGD while
resetting the PGD.
Cc: Marc Zyngier <marc.zyngier@xxxxxxx>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
Reviewed-by: Christoffer Dall <cdall@xxxxxxxxxx>
Signed-off-by: Christoffer Dall <cdall@xxxxxxxxxx>
[bwh: Backported to 3.16:
- s/READ_ONCE/ACCESS_ONCE/
- Adjust filename]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
arch/arm/kvm/mmu.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -643,7 +643,7 @@ void kvm_free_stage2_pgd(struct kvm *kvm
spin_lock(&kvm->mmu_lock);
if (kvm->arch.pgd) {
unmap_stage2_range(kvm, 0, KVM_PHYS_SIZE);
- pgd = kvm->arch.pgd;
+ pgd = ACCESS_ONCE(kvm->arch.pgd);
kvm->arch.pgd = NULL;
}
spin_unlock(&kvm->mmu_lock);