From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751772AbdIIXAD (ORCPT ); Sat, 9 Sep 2017 19:00:03 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:43076 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752279AbdIIW76 (ORCPT ); Sat, 9 Sep 2017 18:59:58 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Christoffer Dall" , "Marc Zyngier" , "Suzuki K Poulose" Date: Sat, 09 Sep 2017 22:47:14 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 028/233] kvm: arm/arm64: Force reading uncached stage2 PGD In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.48-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Suzuki K Poulose commit 2952a6070e07ebdd5896f1f5b861acad677caded upstream. Make sure we don't use a cached value of the KVM stage2 PGD while resetting the PGD. Cc: Marc Zyngier Signed-off-by: Suzuki K Poulose Reviewed-by: Christoffer Dall Signed-off-by: Christoffer Dall [bwh: Backported to 3.16: - s/READ_ONCE/ACCESS_ONCE/ - Adjust filename] Signed-off-by: Ben Hutchings --- 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);