diff options
| author | Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> | 2021-03-17 10:07:19 +0000 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2021-04-22 15:55:21 +0100 |
| commit | 46135d6f878ab00261d4a2082d620bfb41019aab (patch) | |
| tree | 8eaa3ebe27414bcf3116aab3143b415ae0d2b6c8 | |
| parent | a6992bbe9774e044d3d0f973593d655c53efe089 (diff) | |
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 <lorenzo.pieralisi@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210317100719.3331-2-lorenzo.pieralisi@arm.com
| -rw-r--r-- | arch/arm64/kvm/vgic/vgic-mmio-v3.c | 4 | ||||
| -rw-r--r-- | drivers/irqchip/irq-gic-v4.c | 27 | ||||
| -rw-r--r-- | include/linux/irqchip/arm-gic-v4.h | 2 |
3 files changed, 29 insertions, 4 deletions
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 */ diff --git a/drivers/irqchip/irq-gic-v4.c b/drivers/irqchip/irq-gic-v4.c index 5d1dc9915272..4ea71b28f9f5 100644 --- a/drivers/irqchip/irq-gic-v4.c +++ b/drivers/irqchip/irq-gic-v4.c @@ -87,17 +87,40 @@ static struct irq_domain *gic_domain; static const struct irq_domain_ops *vpe_domain_ops; static const struct irq_domain_ops *sgi_domain_ops; +#ifdef CONFIG_ARM64 +#include <asm/cpufeature.h> + +bool gic_cpuif_has_vsgi(void) +{ + unsigned long fld, reg = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1); + + fld = cpuid_feature_extract_unsigned_field(reg, ID_AA64PFR0_GIC_SHIFT); + + return fld >= 0x3; +} +#else +bool gic_cpuif_has_vsgi(void) +{ + return false; +} +#endif + static bool has_v4_1(void) { return !!sgi_domain_ops; } +static bool has_v4_1_sgi(void) +{ + return has_v4_1() && gic_cpuif_has_vsgi(); +} + static int its_alloc_vcpu_sgis(struct its_vpe *vpe, int idx) { char *name; int sgi_base; - if (!has_v4_1()) + if (!has_v4_1_sgi()) return 0; name = kasprintf(GFP_KERNEL, "GICv4-sgi-%d", task_pid_nr(current)); @@ -182,7 +205,7 @@ static void its_free_sgi_irqs(struct its_vm *vm) { int i; - if (!has_v4_1()) + if (!has_v4_1_sgi()) return; for (i = 0; i < vm->nr_vpes; i++) { diff --git a/include/linux/irqchip/arm-gic-v4.h b/include/linux/irqchip/arm-gic-v4.h index 943c3411ca10..2c63375bbd43 100644 --- a/include/linux/irqchip/arm-gic-v4.h +++ b/include/linux/irqchip/arm-gic-v4.h @@ -145,4 +145,6 @@ int its_init_v4(struct irq_domain *domain, const struct irq_domain_ops *vpe_ops, const struct irq_domain_ops *sgi_ops); +bool gic_cpuif_has_vsgi(void); + #endif |