diff options
Diffstat (limited to 'Documentation/virtual')
-rw-r--r-- | Documentation/virtual/kvm/api.txt | 41 |
1 files changed, 39 insertions, 2 deletions
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 0fe36497642c..5c54d196f4c8 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -2863,8 +2863,8 @@ The fields in each entry are defined as follows: this function/index combination -6. Capabilities that can be enabled ------------------------------------ +6. Capabilities that can be enabled on vCPUs +-------------------------------------------- There are certain capabilities that change the behavior of the virtual CPU when enabled. To enable them, please see section 4.37. Below you can find a list of @@ -3002,3 +3002,40 @@ Parameters: args[0] is the XICS device fd args[1] is the XICS CPU number (server ID) for this vcpu This capability connects the vcpu to an in-kernel XICS device. + + +7. Capabilities that can be enabled on VMs +------------------------------------------ + +There are certain capabilities that change the behavior of the virtual +machine when enabled. To enable them, please see section 4.37. Below +you can find a list of capabilities and what their effect on the VM +is when enabling them. + +The following information is provided along with the description: + + Architectures: which instruction set architectures provide this ioctl. + x86 includes both i386 and x86_64. + + Parameters: what parameters are accepted by the capability. + + Returns: the return value. General error numbers (EBADF, ENOMEM, EINVAL) + are not detailed, but errors with specific meanings are. + + +7.1 KVM_CAP_PPC_ENABLE_HCALL + +Architectures: ppc +Parameters: args[0] is the sPAPR hcall number + args[1] is 0 to disable, 1 to enable in-kernel handling + +This capability controls whether individual sPAPR hypercalls (hcalls) +get handled by the kernel or not. Enabling or disabling in-kernel +handling of an hcall is effective across the VM. On creation, an +initial set of hcalls are enabled for in-kernel handling, which +consists of those hcalls for which in-kernel handlers were implemented +before this capability was implemented. If disabled, the kernel will +not to attempt to handle the hcall, but will always exit to userspace +to handle it. Note that it may not make sense to enable some and +disable others of a group of related hcalls, but KVM does not prevent +userspace from doing that. |