From bd94e7aea40387524b1d6c76b09785f5c3319116 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Fri, 27 Oct 2017 15:28:52 +0100 Subject: KVM: arm/arm64: GICv4: Prevent a VM using GICv4 from being saved The GICv4 architecture doesn't make it easy for save/restore to work, as it doesn't give any guarantee that the pending state is written into the pending table. So let's not take any chance, and let's return an error if we encounter any LPI that has the HW bit set. In order for userspace to distinguish this error from other failure modes, use -EACCES as an error code. Reviewed-by: Eric Auger Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall --- Documentation/virtual/kvm/devices/arm-vgic-its.txt | 2 ++ 1 file changed, 2 insertions(+) (limited to 'Documentation') diff --git a/Documentation/virtual/kvm/devices/arm-vgic-its.txt b/Documentation/virtual/kvm/devices/arm-vgic-its.txt index 8d5830eab26a..4f0c9fc40365 100644 --- a/Documentation/virtual/kvm/devices/arm-vgic-its.txt +++ b/Documentation/virtual/kvm/devices/arm-vgic-its.txt @@ -64,6 +64,8 @@ Groups: -EINVAL: Inconsistent restored data -EFAULT: Invalid guest ram access -EBUSY: One or more VCPUS are running + -EACCES: The virtual ITS is backed by a physical GICv4 ITS, and the + state is not available KVM_DEV_ARM_VGIC_GRP_ITS_REGS Attributes: -- cgit v1.2.3 From a75460547e13c99762c2f9dbfcdd13ad416f91c5 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Fri, 27 Oct 2017 15:28:54 +0100 Subject: KVM: arm/arm64: GICv4: Enable VLPI support All it takes is the has_v4 flag to be set in gic_kvm_info as well as "kvm-arm.vgic_v4_enable=1" being passed on the command line for GICv4 to be enabled in KVM. Acked-by: Christoffer Dall Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall --- Documentation/admin-guide/kernel-parameters.txt | 4 ++++ virt/kvm/arm/vgic/vgic-v3.c | 14 ++++++++++++++ 2 files changed, 18 insertions(+) (limited to 'Documentation') diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 3daa0a590236..6f897a4c8281 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1881,6 +1881,10 @@ [KVM,ARM] Trap guest accesses to GICv3 common system registers + kvm-arm.vgic_v4_enable= + [KVM,ARM] Allow use of GICv4 for direct injection of + LPIs. + kvm-intel.ept= [KVM,Intel] Disable extended page tables (virtualized MMU) support on capable Intel chips. Default is 1 (enabled) diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c index 863351c090d8..2f05f732d3fd 100644 --- a/virt/kvm/arm/vgic/vgic-v3.c +++ b/virt/kvm/arm/vgic/vgic-v3.c @@ -24,6 +24,7 @@ static bool group0_trap; static bool group1_trap; static bool common_trap; +static bool gicv4_enable; void vgic_v3_set_underflow(struct kvm_vcpu *vcpu) { @@ -461,6 +462,12 @@ static int __init early_common_trap_cfg(char *buf) } early_param("kvm-arm.vgic_v3_common_trap", early_common_trap_cfg); +static int __init early_gicv4_enable(char *buf) +{ + return strtobool(buf, &gicv4_enable); +} +early_param("kvm-arm.vgic_v4_enable", early_gicv4_enable); + /** * vgic_v3_probe - probe for a GICv3 compatible interrupt controller in DT * @node: pointer to the DT node @@ -480,6 +487,13 @@ int vgic_v3_probe(const struct gic_kvm_info *info) kvm_vgic_global_state.can_emulate_gicv2 = false; kvm_vgic_global_state.ich_vtr_el2 = ich_vtr_el2; + /* GICv4 support? */ + if (info->has_v4) { + kvm_vgic_global_state.has_gicv4 = gicv4_enable; + kvm_info("GICv4 support %sabled\n", + gicv4_enable ? "en" : "dis"); + } + if (!info->vcpu.start) { kvm_info("GICv3: no GICV resource entry\n"); kvm_vgic_global_state.vcpu_base = 0; -- cgit v1.2.3