On Mon, Apr 16, 2018 at 10:46:01PM -0700, Wanpeng Li wrote:
> From: Wanpeng Li <wanpengli@xxxxxxxxxxx>
>
> Allow to disable ioport intercept by userspace.
>
> Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> Cc: Radim Krčmář <rkrcmar@xxxxxxxxxx>
> Cc: Tim Shearer <tshearer@xxxxxxxxxxxxxxx>
> Cc: Liran Alon <liran.alon@xxxxxxxxxx>
> Signed-off-by: Wanpeng Li <wanpengli@xxxxxxxxxxx>
> ---
> Documentation/virtual/kvm/api.txt | 11 +++++++++++
> arch/x86/include/asm/kvm_host.h | 2 ++
> arch/x86/kvm/x86.c | 5 +++++
> include/uapi/linux/kvm.h | 1 +
> 4 files changed, 19 insertions(+)
>
> diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
> index 1c7958b..3d0488e 100644
> --- a/Documentation/virtual/kvm/api.txt
> +++ b/Documentation/virtual/kvm/api.txt
> @@ -4378,6 +4378,17 @@ all such vmexits.
>
> Do not enable KVM_FEATURE_PV_UNHALT if you disable HLT exits.
>
> +7.14 KVM_CAP_IOPORT_DISABLE_INTERCEPT
> +
> +Architectures: x86
> +Parameters: args[0] defines whether ioport intercept
"defines whether ioport intercept" -> "defines whether to intercept the provided ioport"
> +
> +When disable intercept (args[0] == 1), some ioports which frequently
When args[0] == 1 is one, that is disable intercept, some ioports..
> +access will not be intercepted.
Why not proide args[1] which will have the ioport in questions? Or an array
of them?
> +
> +When enable intercept (args[0] == 0), behavior is as if this facility
> +is unsupported.
> +
> 8. Other capabilities.
> ----------------------
>
> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
> index c25775f..2f29f64 100644
> --- a/arch/x86/include/asm/kvm_host.h
> +++ b/arch/x86/include/asm/kvm_host.h
> @@ -808,6 +808,8 @@ struct kvm_arch {
> bool hlt_in_guest;
> bool pause_in_guest;
>
> + bool ioport_disable_intercept;
> +
> unsigned long irq_sources_bitmap;
> s64 kvmclock_offset;
> raw_spinlock_t tsc_write_lock;
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 51ecd38..044e314 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -2881,6 +2881,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
> case KVM_CAP_SPLIT_IRQCHIP:
> case KVM_CAP_IMMEDIATE_EXIT:
> case KVM_CAP_GET_MSR_FEATURES:
> + case KVM_CAP_IOPORT_DISABLE_INTERCEPT:
> r = 1;
> break;
> case KVM_CAP_SYNC_REGS:
> @@ -4250,6 +4251,10 @@ static int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
> kvm->arch.pause_in_guest = true;
> r = 0;
> break;
> + case KVM_CAP_IOPORT_DISABLE_INTERCEPT:
> + kvm->arch.ioport_disable_intercept = cap->args[0];
> + r = 0;
> + break;
> default:
> r = -EINVAL;
> break;
> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
> index 1065006..92730d8 100644
> --- a/include/uapi/linux/kvm.h
> +++ b/include/uapi/linux/kvm.h
> @@ -941,6 +941,7 @@ struct kvm_ppc_resize_hpt {
> #define KVM_CAP_S390_BPB 152
> #define KVM_CAP_GET_MSR_FEATURES 153
> #define KVM_CAP_HYPERV_EVENTFD 154
> +#define KVM_CAP_IOPORT_DISABLE_INTERCEPT 155
>
> #ifdef KVM_CAP_IRQ_ROUTING
>
> --
> 2.7.4
>
