[PATCH v4 24/26] KVM: arm/arm64: GICv4: Enable VLPI support

Marc Zyngier
2017-10-06T15:34:26Z

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 <cdall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
Documentation/admin-guide/kernel-parameters.txt | 4 ++++
virt/kvm/arm/vgic/vgic-v3.c | 14 ++++++++++++++
2 files changed, 18 insertions(+)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 05496622b4ef..93c8fff399eb 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -1874,6 +1874,10 @@
[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 96ea597db0e7..405733678c2f 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)
{
@@ -459,6 +460,12 @@ 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
@@ -478,6 +485,13 @@ 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;
--
2.14.1