Now that we're able to safely handle common sysreg access, let's
give the user the opportunity to enable it by passing a specific
command-line option (vgic_v3.common_trap).
Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
---
include/linux/irqchip/arm-gic-v3.h | 1 +
virt/kvm/arm/vgic/vgic-v3.c | 11 ++++++++++-
2 files changed, 11 insertions(+), 1 deletion(-)
diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h
index 46a1e0943cf8..f0cebb6e57d0 100644
--- a/include/linux/irqchip/arm-gic-v3.h
+++ b/include/linux/irqchip/arm-gic-v3.h
@@ -417,6 +417,7 @@
#define ICH_HCR_EN (1 << 0)
#define ICH_HCR_UIE (1 << 1)
+#define ICH_HCR_TC (1 << 10)
#define ICH_HCR_TALL0 (1 << 11)
#define ICH_HCR_TALL1 (1 << 12)
#define ICH_HCR_EOIcount_SHIFT 27
diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c
index 062be1fe95b5..636f1258d217 100644
--- a/virt/kvm/arm/vgic/vgic-v3.c
+++ b/virt/kvm/arm/vgic/vgic-v3.c
@@ -23,6 +23,7 @@
static bool group0_trap;
static bool group1_trap;
+static bool common_trap;
void vgic_v3_set_underflow(struct kvm_vcpu *vcpu)
{
@@ -246,6 +247,8 @@ void vgic_v3_enable(struct kvm_vcpu *vcpu)
vgic_v3->vgic_hcr |= ICH_HCR_TALL0;
if (group1_trap)
vgic_v3->vgic_hcr |= ICH_HCR_TALL1;
+ if (common_trap)
+ vgic_v3->vgic_hcr |= ICH_HCR_TC;
}
int vgic_v3_lpi_sync_pending_status(struct kvm *kvm, struct vgic_irq *irq)
@@ -431,6 +434,12 @@ static int __init early_group1_trap_cfg(char *buf)
}
early_param("vgic_v3.group1_trap", early_group1_trap_cfg);
+static int __init early_common_trap_cfg(char *buf)
+{
+ return strtobool(buf, &common_trap);
+}
+early_param("vgic_v3.common_trap", early_common_trap_cfg);
+
/**
* vgic_v3_probe - probe for a GICv3 compatible interrupt controller in DT
* @node: pointer to the DT node
@@ -489,7 +498,7 @@ int vgic_v3_probe(const struct gic_kvm_info *info)
}
#endif
- if (group0_trap || group1_trap) {
+ if (group0_trap || group1_trap || common_trap) {
kvm_info("GICv3 sysreg trapping enabled (reduced performance)\n");
static_branch_enable(&vgic_v3_cpuif_trap);
}
--
2.11.0
