This is a note to let you know that I've just added the patch titled KVM: arm/arm64: vgic: Don't flush/sync without a working vgic to the 4.8-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-vgic-don-t-flush-sync-without-a-working-vgic.patch and it can be found in the queue-4.8 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 0099b7701f5296a758d9e6b945ec96f96847cc2f Mon Sep 17 00:00:00 2001 From: Christoffer Dall <christoffer.dall@xxxxxxxxxx> Date: Tue, 27 Sep 2016 18:53:35 +0200 Subject: KVM: arm/arm64: vgic: Don't flush/sync without a working vgic From: Christoffer Dall <christoffer.dall@xxxxxxxxxx> commit 0099b7701f5296a758d9e6b945ec96f96847cc2f upstream. If the vgic hasn't been created and initialized, we shouldn't attempt to look at its data structures or flush/sync anything to the GIC hardware. This fixes an issue reported by Alexander Graf when using a userspace irqchip. Fixes: 0919e84c0fc1 ("KVM: arm/arm64: vgic-new: Add IRQ sync/flush framework") Reported-by: Alexander Graf <agraf@xxxxxxx> Acked-by: Marc Zyngier <marc.zyngier@xxxxxxx> Signed-off-by: Christoffer Dall <christoffer.dall@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- virt/kvm/arm/vgic/vgic.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/virt/kvm/arm/vgic/vgic.c +++ b/virt/kvm/arm/vgic/vgic.c @@ -645,6 +645,9 @@ next: /* Sync back the hardware VGIC state into our emulation after a guest's run. */ void kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu) { + if (unlikely(!vgic_initialized(vcpu->kvm))) + return; + vgic_process_maintenance_interrupt(vcpu); vgic_fold_lr_state(vcpu); vgic_prune_ap_list(vcpu); @@ -653,6 +656,9 @@ void kvm_vgic_sync_hwstate(struct kvm_vc /* Flush our emulation state into the GIC hardware before entering the guest. */ void kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu) { + if (unlikely(!vgic_initialized(vcpu->kvm))) + return; + spin_lock(&vcpu->arch.vgic_cpu.ap_list_lock); vgic_flush_lr_state(vcpu); spin_unlock(&vcpu->arch.vgic_cpu.ap_list_lock); Patches currently in stable-queue which might be from christoffer.dall@xxxxxxxxxx are queue-4.8/kvm-arm64-require-in-kernel-irqchip-for-pmu-support.patch queue-4.8/kvm-arm-arm64-vgic-don-t-flush-sync-without-a-working-vgic.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html