KVM: arm/arm64: Don't assume initialized vgic when setting PMU IRQ

The PMU IRQ number is set through the VCPU device's KVM_SET_DEVICE_ATTR
ioctl handler for the KVM_ARM_VCPU_PMU_V3_IRQ attribute, but there is no
enforced or stated requirement that this must happen after initializing
the VGIC.  As a result, calling vgic_valid_spi() which relies on the
nr_spis being set during the VGIC init can incorrectly fail.

Introduce irq_is_spi, which determines if an IRQ number is within the
SPI range without verifying it against the actual VGIC properties.

Signed-off-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
This commit is contained in:
Christoffer Dall 2017-05-16 19:53:50 +02:00
parent cb3f0ad881
commit ebb127f2d6
2 changed files with 20 additions and 4 deletions

View File

@ -39,6 +39,8 @@
#define KVM_IRQCHIP_NUM_PINS (1020 - 32)
#define irq_is_ppi(irq) ((irq) >= VGIC_NR_SGIS && (irq) < VGIC_NR_PRIVATE_IRQS)
#define irq_is_spi(irq) ((irq) >= VGIC_NR_PRIVATE_IRQS && \
(irq) <= VGIC_MAX_SPI)
enum vgic_type {
VGIC_V2, /* Good ol' GICv2 */

View File

@ -458,10 +458,24 @@ int kvm_arm_pmu_v3_enable(struct kvm_vcpu *vcpu)
/*
* A valid interrupt configuration for the PMU is either to have a
* properly configured interrupt number and using an in-kernel
* irqchip, or to neither set an IRQ nor create an in-kernel irqchip.
* irqchip, or to not have an in-kernel GIC and not set an IRQ.
*/
if (kvm_arm_pmu_irq_initialized(vcpu) != irqchip_in_kernel(vcpu->kvm))
return -EINVAL;
if (irqchip_in_kernel(vcpu->kvm)) {
int irq = vcpu->arch.pmu.irq_num;
if (!kvm_arm_pmu_irq_initialized(vcpu))
return -EINVAL;
/*
* If we are using an in-kernel vgic, at this point we know
* the vgic will be initialized, so we can check the PMU irq
* number against the dimensions of the vgic and make sure
* it's valid.
*/
if (!irq_is_ppi(irq) && !vgic_valid_spi(vcpu->kvm, irq))
return -EINVAL;
} else if (kvm_arm_pmu_irq_initialized(vcpu)) {
return -EINVAL;
}
kvm_pmu_vcpu_reset(vcpu);
vcpu->arch.pmu.ready = true;
@ -547,7 +561,7 @@ int kvm_arm_pmu_v3_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
return -EFAULT;
/* The PMU overflow interrupt can be a PPI or a valid SPI. */
if (!(irq_is_ppi(irq) || vgic_valid_spi(vcpu->kvm, irq)))
if (!(irq_is_ppi(irq) || irq_is_spi(irq)))
return -EINVAL;
if (!pmu_irq_is_valid(vcpu->kvm, irq))