On 9/18/2020 3:55 PM, Andrew Jones wrote: > On Thu, Sep 17, 2020 at 08:01:01PM +0800, Peng Liang wrote: >> Add KVM_CAP_ARM_CPU_FEATURE extension for userpace to check whether KVM >> supports to set CPU features in AArch64. >> >> Signed-off-by: zhanghailiang <zhang.zhanghailiang@xxxxxxxxxx> >> Signed-off-by: Peng Liang <liangpeng10@xxxxxxxxxx> >> --- >> Documentation/virt/kvm/api.rst | 8 ++++++++ >> arch/arm64/kvm/arm.c | 1 + >> include/uapi/linux/kvm.h | 1 + >> 3 files changed, 10 insertions(+) >> >> diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst >> index d2b733dc7892..50214ed8f50e 100644 >> --- a/Documentation/virt/kvm/api.rst >> +++ b/Documentation/virt/kvm/api.rst >> @@ -6173,3 +6173,11 @@ specific interfaces must be consistent, i.e. if one says the feature >> is supported, than the other should as well and vice versa. For arm64 >> see Documentation/virt/kvm/devices/vcpu.rst "KVM_ARM_VCPU_PVTIME_CTRL". >> For x86 see Documentation/virt/kvm/msr.rst "MSR_KVM_STEAL_TIME". >> + >> +8.25 KVM_CAP_ARM_CPU_FEATURE >> +----------------------------------- > > Too many '----' > >> + >> +:Architecture: arm64 >> + >> +This capability indicates that userspace can modify the ID registers via >> +KVM_SET_ONE_REG ioctl. > > You should say something like "See KVM_SET_ONE_REG:ARM64 ID Registers" > here and also extend the "KVM_SET_ONE_REG" section with a "ARM64 ID > Register" section that describes the limits and return values. > >> diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c >> index 6d961e192268..918a7a56b224 100644 >> --- a/arch/arm64/kvm/arm.c >> +++ b/arch/arm64/kvm/arm.c >> @@ -178,6 +178,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) >> case KVM_CAP_ARM_IRQ_LINE_LAYOUT_2: >> case KVM_CAP_ARM_NISV_TO_USER: >> case KVM_CAP_ARM_INJECT_EXT_DABT: >> + case KVM_CAP_ARM_CPU_FEATURE: >> r = 1; >> break; >> case KVM_CAP_ARM_SET_DEVICE_ADDR: >> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h >> index 7d8eced6f459..12356beadd5a 100644 >> --- a/include/uapi/linux/kvm.h >> +++ b/include/uapi/linux/kvm.h >> @@ -1037,6 +1037,7 @@ struct kvm_ppc_resize_hpt { >> #define KVM_CAP_SMALLER_MAXPHYADDR 185 >> #define KVM_CAP_S390_DIAG318 186 >> #define KVM_CAP_STEAL_TIME 187 >> +#define KVM_CAP_ARM_CPU_FEATURE 188 >> >> #ifdef KVM_CAP_IRQ_ROUTING >> >> -- >> 2.26.2 >> > > Thanks, > drew > > . > Thank you for your advise. I'll change them in next version. Thanks, Peng