Re: [PATCH v4 1/4] RISC-V: KVM: Forward SBI experimental and vendor extensions

From: Anup Patel
Date: Tue Dec 28 2021 - 01:21:21 EST


On Fri, Dec 24, 2021 at 1:06 PM Anup Patel <anup.patel@xxxxxxx> wrote:
>
> The SBI experimental extension space is for temporary (or experimental)
> stuff whereas SBI vendor extension space is for hardware vendor specific
> stuff. Both these SBI extension spaces won't be standardized by the SBI
> specification so let's blindly forward such SBI calls to the userspace.
>
> Signed-off-by: Anup Patel <anup.patel@xxxxxxx>
> Reviewed-and-tested-by: Atish Patra <atishp@xxxxxxxxxxxx>

Queued this patch for 5.17

Thanks,
Anup

> ---
> arch/riscv/kvm/vcpu_sbi.c | 4 ++++
> arch/riscv/kvm/vcpu_sbi_base.c | 27 +++++++++++++++++++++++++++
> 2 files changed, 31 insertions(+)
>
> diff --git a/arch/riscv/kvm/vcpu_sbi.c b/arch/riscv/kvm/vcpu_sbi.c
> index f62d25bc9733..78aa3db76225 100644
> --- a/arch/riscv/kvm/vcpu_sbi.c
> +++ b/arch/riscv/kvm/vcpu_sbi.c
> @@ -46,6 +46,8 @@ extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_time;
> extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_ipi;
> extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_rfence;
> extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_hsm;
> +extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_experimental;
> +extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_vendor;
>
> static const struct kvm_vcpu_sbi_extension *sbi_ext[] = {
> &vcpu_sbi_ext_v01,
> @@ -54,6 +56,8 @@ static const struct kvm_vcpu_sbi_extension *sbi_ext[] = {
> &vcpu_sbi_ext_ipi,
> &vcpu_sbi_ext_rfence,
> &vcpu_sbi_ext_hsm,
> + &vcpu_sbi_ext_experimental,
> + &vcpu_sbi_ext_vendor,
> };
>
> void kvm_riscv_vcpu_sbi_forward(struct kvm_vcpu *vcpu, struct kvm_run *run)
> diff --git a/arch/riscv/kvm/vcpu_sbi_base.c b/arch/riscv/kvm/vcpu_sbi_base.c
> index d1ec08fe7289..4ecf377f483b 100644
> --- a/arch/riscv/kvm/vcpu_sbi_base.c
> +++ b/arch/riscv/kvm/vcpu_sbi_base.c
> @@ -70,3 +70,30 @@ const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_base = {
> .extid_end = SBI_EXT_BASE,
> .handler = kvm_sbi_ext_base_handler,
> };
> +
> +static int kvm_sbi_ext_forward_handler(struct kvm_vcpu *vcpu,
> + struct kvm_run *run,
> + unsigned long *out_val,
> + struct kvm_cpu_trap *utrap,
> + bool *exit)
> +{
> + /*
> + * Both SBI experimental and vendor extensions are
> + * unconditionally forwarded to userspace.
> + */
> + kvm_riscv_vcpu_sbi_forward(vcpu, run);
> + *exit = true;
> + return 0;
> +}
> +
> +const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_experimental = {
> + .extid_start = SBI_EXT_EXPERIMENTAL_START,
> + .extid_end = SBI_EXT_EXPERIMENTAL_END,
> + .handler = kvm_sbi_ext_forward_handler,
> +};
> +
> +const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_vendor = {
> + .extid_start = SBI_EXT_VENDOR_START,
> + .extid_end = SBI_EXT_VENDOR_END,
> + .handler = kvm_sbi_ext_forward_handler,
> +};
> --
> 2.25.1
>