From 46135d6f878ab00261d4a2082d620bfb41019aab Mon Sep 17 00:00:00 2001 From: Lorenzo Pieralisi Date: Wed, 17 Mar 2021 10:07:19 +0000 Subject: irqchip/gic-v4.1: Disable vSGI upon (GIC CPUIF < v4.1) detection GIC CPU interfaces versions predating GIC v4.1 were not built to accommodate vINTID within the vSGI range; as reported in the GIC specifications (8.2 "Changes to the CPU interface"), it is CONSTRAINED UNPREDICTABLE to deliver a vSGI to a PE with ID_AA64PFR0_EL1.GIC < b0011. Check the GIC CPUIF version by reading the SYS_ID_AA64_PFR0_EL1. Disable vSGIs if a CPUIF version < 4.1 is detected to prevent using vSGIs on systems where they may misbehave. Signed-off-by: Lorenzo Pieralisi Cc: Marc Zyngier Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20210317100719.3331-2-lorenzo.pieralisi@arm.com --- arch/arm64/kvm/vgic/vgic-mmio-v3.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/arm64') diff --git a/arch/arm64/kvm/vgic/vgic-mmio-v3.c b/arch/arm64/kvm/vgic/vgic-mmio-v3.c index 15a6c98ee92f..2f1b156021a6 100644 --- a/arch/arm64/kvm/vgic/vgic-mmio-v3.c +++ b/arch/arm64/kvm/vgic/vgic-mmio-v3.c @@ -86,7 +86,7 @@ static unsigned long vgic_mmio_read_v3_misc(struct kvm_vcpu *vcpu, } break; case GICD_TYPER2: - if (kvm_vgic_global_state.has_gicv4_1) + if (kvm_vgic_global_state.has_gicv4_1 && gic_cpuif_has_vsgi()) value = GICD_TYPER2_nASSGIcap; break; case GICD_IIDR: @@ -119,7 +119,7 @@ static void vgic_mmio_write_v3_misc(struct kvm_vcpu *vcpu, dist->enabled = val & GICD_CTLR_ENABLE_SS_G1; /* Not a GICv4.1? No HW SGIs */ - if (!kvm_vgic_global_state.has_gicv4_1) + if (!kvm_vgic_global_state.has_gicv4_1 || !gic_cpuif_has_vsgi()) val &= ~GICD_CTLR_nASSGIreq; /* Dist stays enabled? nASSGIreq is RO */ -- cgit v1.2.3