From 1caa71a7a600f7781ce05ef1e84701c459653663 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Wed, 7 Jun 2023 15:38:44 +0100 Subject: [PATCH] KVM: arm64: Restore GICv2-on-GICv3 functionality When reworking the vgic locking, the vgic distributor registration got simplified, which was a very good cleanup. But just a tad too radical, as we now register the *native* vgic only, ignoring the GICv2-on-GICv3 that allows pre-historic VMs (or so I thought) to run. As it turns out, QEMU still defaults to GICv2 in some cases, and this breaks Nathan's setup! Fix it by propagating the *requested* vgic type rather than the host's version. Fixes: 59112e9c390b ("KVM: arm64: vgic: Fix a circular locking issue") Reported-by: Nathan Chancellor Tested-by: Nathan Chancellor Signed-off-by: Marc Zyngier link: https://lore.kernel.org/r/20230606221525.GA2269598@dev-arch.thelio-3990X --- arch/arm64/kvm/vgic/vgic-init.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/arch/arm64/kvm/vgic/vgic-init.c b/arch/arm64/kvm/vgic/vgic-init.c index 6eafc2c45cfc..c8c3cb812783 100644 --- a/arch/arm64/kvm/vgic/vgic-init.c +++ b/arch/arm64/kvm/vgic/vgic-init.c @@ -446,6 +446,7 @@ int vgic_lazy_init(struct kvm *kvm) int kvm_vgic_map_resources(struct kvm *kvm) { struct vgic_dist *dist = &kvm->arch.vgic; + enum vgic_type type; gpa_t dist_base; int ret = 0; @@ -460,10 +461,13 @@ int kvm_vgic_map_resources(struct kvm *kvm) if (!irqchip_in_kernel(kvm)) goto out; - if (dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V2) + if (dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V2) { ret = vgic_v2_map_resources(kvm); - else + type = VGIC_V2; + } else { ret = vgic_v3_map_resources(kvm); + type = VGIC_V3; + } if (ret) { __kvm_vgic_destroy(kvm); @@ -473,8 +477,7 @@ int kvm_vgic_map_resources(struct kvm *kvm) dist_base = dist->vgic_dist_base; mutex_unlock(&kvm->arch.config_lock); - ret = vgic_register_dist_iodev(kvm, dist_base, - kvm_vgic_global_state.type); + ret = vgic_register_dist_iodev(kvm, dist_base, type); if (ret) { kvm_err("Unable to register VGIC dist MMIO regions\n"); kvm_vgic_destroy(kvm);