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Diffstat (limited to 'Documentation/virtual/kvm/api.txt')
| -rw-r--r-- | Documentation/virtual/kvm/api.txt | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 8cc857fffcc7..a4482cce4bae 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -199,8 +199,8 @@ Type: vm ioctl Parameters: vcpu id (apic id on x86) Returns: vcpu fd on success, -1 on error -This API adds a vcpu to a virtual machine. The vcpu id is a small integer -in the range [0, max_vcpus). +This API adds a vcpu to a virtual machine. No more than max_vcpus may be added. +The vcpu id is an integer in the range [0, max_vcpu_id). The recommended max_vcpus value can be retrieved using the KVM_CAP_NR_VCPUS of the KVM_CHECK_EXTENSION ioctl() at run-time. @@ -212,6 +212,12 @@ cpus max. If the KVM_CAP_MAX_VCPUS does not exist, you should assume that max_vcpus is same as the value returned from KVM_CAP_NR_VCPUS. +The maximum possible value for max_vcpu_id can be retrieved using the +KVM_CAP_MAX_VCPU_ID of the KVM_CHECK_EXTENSION ioctl() at run-time. + +If the KVM_CAP_MAX_VCPU_ID does not exist, you should assume that max_vcpu_id +is the same as the value returned from KVM_CAP_MAX_VCPUS. + On powerpc using book3s_hv mode, the vcpus are mapped onto virtual threads in one or more virtual CPU cores. (This is because the hardware requires all the hardware threads in a CPU core to be in the |