diff mbox series

[v3,04/11] KVM: arm64: vgic-v2: Use cpuid from userspace as vcpu_id

Message ID 20230927090911.3355209-5-maz@kernel.org (mailing list archive)
State New, archived
Headers show
Series KVM: arm64: Accelerate lookup of vcpus by MPIDR values (and other fixes) | expand

Commit Message

Marc Zyngier Sept. 27, 2023, 9:09 a.m. UTC 
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: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 arch/arm64/kvm/vgic/vgic-kvm-device.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)
diff mbox series

Patch

diff --git a/arch/arm64/kvm/vgic/vgic-kvm-device.c b/arch/arm64/kvm/vgic/vgic-kvm-device.c
index 212b73a715c1..c11962f901e0 100644
--- a/arch/arm64/kvm/vgic/vgic-kvm-device.c
+++ b/arch/arm64/kvm/vgic/vgic-kvm-device.c
@@ -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;