Commit 4e7728c8 authored by Marc Zyngier's avatar Marc Zyngier Committed by Oliver Upton
Browse files

KVM: arm64: vgic-v2: Use cpuid from userspace as vcpu_id 



When parsing a GICv2 attribute that contains a cpuid, handle this
as the vcpu_id, not a vcpu_idx, as userspace cannot really know
the mapping between the two. For this, use kvm_get_vcpu_by_id()
instead of kvm_get_vcpu().

Take this opportunity to get rid of the pointless check against
online_vcpus, which doesn't make much sense either, and switch
to FIELD_GET as a way to extract the vcpu_id.

Reviewed-by: default avatarZenghui Yu <yuzenghui@huawei.com>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230927090911.3355209-5-maz@kernel.org


Signed-off-by: default avatarOliver Upton <oliver.upton@linux.dev>
parent f3f60a56

arch/arm64/kvm/vgic/vgic-kvm-device.c

+2 −6
Original line number Diff line number Diff line
@@ -339,13 +339,9 @@ int vgic_v2_parse_attr(struct kvm_device *dev, struct kvm_device_attr *attr, 
{

	int cpuid;



	cpuid = (attr->attr & KVM_DEV_ARM_VGIC_CPUID_MASK) >>

		 KVM_DEV_ARM_VGIC_CPUID_SHIFT;

	cpuid = FIELD_GET(KVM_DEV_ARM_VGIC_CPUID_MASK, attr->attr);



	if (cpuid >= atomic_read(&dev->kvm->online_vcpus))

		return -EINVAL;



	reg_attr->vcpu = kvm_get_vcpu(dev->kvm, cpuid);

	reg_attr->vcpu = kvm_get_vcpu_by_id(dev->kvm, cpuid);

	reg_attr->addr = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK;



	return 0;