Re: [PATCH] RISC-V: KVM: Allow Zbb extension for Guest/VM

[Atish Patra]

On Sat, Apr 1, 2023 at 4:57 PM Anup Patel <apatel@xxxxxxxxxxxxxxxx> wrote:
>
> We extend the KVM ISA extension ONE_REG interface to allow KVM
> user space to detect and enable Zbb extension for Guest/VM.
>
> Signed-off-by: Anup Patel <apatel@xxxxxxxxxxxxxxxx>
> ---
>  arch/riscv/include/uapi/asm/kvm.h | 1 +
>  arch/riscv/kvm/vcpu.c             | 2 ++
>  2 files changed, 3 insertions(+)
>
> diff --git a/arch/riscv/include/uapi/asm/kvm.h b/arch/riscv/include/uapi/asm/kvm.h
> index d8ead5952ed9..47a7c3958229 100644
> --- a/arch/riscv/include/uapi/asm/kvm.h
> +++ b/arch/riscv/include/uapi/asm/kvm.h
> @@ -106,6 +106,7 @@ enum KVM_RISCV_ISA_EXT_ID {
>         KVM_RISCV_ISA_EXT_SVINVAL,
>         KVM_RISCV_ISA_EXT_ZIHINTPAUSE,
>         KVM_RISCV_ISA_EXT_ZICBOM,
> +       KVM_RISCV_ISA_EXT_ZBB,
>         KVM_RISCV_ISA_EXT_MAX,
>  };
>
> diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c
> index 3112697cb12d..02b49cb94561 100644
> --- a/arch/riscv/kvm/vcpu.c
> +++ b/arch/riscv/kvm/vcpu.c
> @@ -61,6 +61,7 @@ static const unsigned long kvm_isa_ext_arr[] = {
>         KVM_ISA_EXT_ARR(SSTC),
>         KVM_ISA_EXT_ARR(SVINVAL),
>         KVM_ISA_EXT_ARR(SVPBMT),
> +       KVM_ISA_EXT_ARR(ZBB),
>         KVM_ISA_EXT_ARR(ZIHINTPAUSE),
>         KVM_ISA_EXT_ARR(ZICBOM),
>  };
> @@ -99,6 +100,7 @@ static bool kvm_riscv_vcpu_isa_disable_allowed(unsigned long ext)
>         case KVM_RISCV_ISA_EXT_SSTC:
>         case KVM_RISCV_ISA_EXT_SVINVAL:
>         case KVM_RISCV_ISA_EXT_ZIHINTPAUSE:
> +       case KVM_RISCV_ISA_EXT_ZBB:
>                 return false;
>         default:
>                 break;
> --
> 2.34.1
>

Reviewed-by: Atish Patra <atishp@xxxxxxxxxxxx>

-- 
Regards,
Atish