This is a note to let you know that I've just added the patch titled KVM: arm/arm64: Handle hva aging while destroying the vm to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: kvm-arm-arm64-handle-hva-aging-while-destroying-the-vm.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 7e5a672289c9754d07e1c3b33649786d3d70f5e4 Mon Sep 17 00:00:00 2001 From: Suzuki K Poulose <Suzuki.Poulose@xxxxxxx> Date: Wed, 5 Jul 2017 09:57:00 +0100 Subject: KVM: arm/arm64: Handle hva aging while destroying the vm From: Suzuki K Poulose <Suzuki.Poulose@xxxxxxx> commit 7e5a672289c9754d07e1c3b33649786d3d70f5e4 upstream. The mmu_notifier_release() callback of KVM triggers cleaning up the stage2 page table on kvm-arm. However there could be other notifier callbacks in parallel with the mmu_notifier_release(), which could cause the call backs ending up in an empty stage2 page table. Make sure we check it for all the notifier callbacks. Fixes: commit 293f29363 ("kvm-arm: Unmap shadow pagetables properly") Reported-by: Alex Graf <agraf@xxxxxxx> Reviewed-by: Christoffer Dall <cdall@xxxxxxxxxx> Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx> Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/arm/kvm/mmu.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -1629,12 +1629,16 @@ static int kvm_test_age_hva_handler(stru int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end) { + if (!kvm->arch.pgd) + return 0; trace_kvm_age_hva(start, end); return handle_hva_to_gpa(kvm, start, end, kvm_age_hva_handler, NULL); } int kvm_test_age_hva(struct kvm *kvm, unsigned long hva) { + if (!kvm->arch.pgd) + return 0; trace_kvm_test_age_hva(hva); return handle_hva_to_gpa(kvm, hva, hva, kvm_test_age_hva_handler, NULL); } Patches currently in stable-queue which might be from Suzuki.Poulose@xxxxxxx are queue-4.4/kvm-arm-arm64-handle-hva-aging-while-destroying-the-vm.patch