diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/include/asm/kvm_host.h | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 0532f4e84308..59da1fbf5248 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -39,7 +39,19 @@ #define KVM_MAX_VCPUS 288 #define KVM_SOFT_MAX_VCPUS 240 -#define KVM_MAX_VCPU_ID 1023 + +/* + * In x86, the VCPU ID corresponds to the APIC ID, and APIC IDs + * might be larger than the actual number of VCPUs because the + * APIC ID encodes CPU topology information. + * + * In the worst case, we'll need less than one extra bit for the + * Core ID, and less than one extra bit for the Package (Die) ID, + * so ratio of 4 should be enough. + */ +#define KVM_VCPU_ID_RATIO 4 +#define KVM_MAX_VCPU_ID (KVM_MAX_VCPUS * KVM_VCPU_ID_RATIO) + /* memory slots that are not exposed to userspace */ #define KVM_PRIVATE_MEM_SLOTS 3 |