[PULL,10/13] kvm: arm/arm64: Force reading uncached stage2 PGD

Message ID 20170518094722.9926-11-cdall@linaro.org
State Accepted
Commit 2952a6070e07ebdd5896f1f5b861acad677caded
Headers show
Series
  • Untitled series #1481
Related show

Commit Message

Christoffer Dall May 18, 2017, 9:47 a.m.
From: Suzuki K Poulose <suzuki.poulose@arm.com>


Make sure we don't use a cached value of the KVM stage2 PGD while
resetting the PGD.

Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>

Reviewed-by: Christoffer Dall <cdall@linaro.org>

Signed-off-by: Christoffer Dall <cdall@linaro.org>

---
 virt/kvm/arm/mmu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

-- 
2.9.0

Patch

diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c
index 909a1a7..704e35f 100644
--- a/virt/kvm/arm/mmu.c
+++ b/virt/kvm/arm/mmu.c
@@ -837,7 +837,7 @@  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 = READ_ONCE(kvm->arch.pgd);
 		kvm->arch.pgd = NULL;
 	}
 	spin_unlock(&kvm->mmu_lock);