Re: [RFC PATCH v3 09/36] KVM: Introduce kvm_arch_pre_create_vcpu()

[Isaku Yamahata]

On Thu, Mar 17, 2022 at 09:58:46PM +0800,
Xiaoyao Li <xiaoyao.li@intel.com> wrote:

> Introduce kvm_arch_pre_create_vcpu(), to perform arch-dependent
> work prior to create any vcpu. This is for i386 TDX because it needs
> call TDX_INIT_VM before creating any vcpu.
> 
> Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
> ---
>  accel/kvm/kvm-all.c    | 7 +++++++
>  include/sysemu/kvm.h   | 1 +
>  target/arm/kvm64.c     | 5 +++++
>  target/i386/kvm/kvm.c  | 5 +++++
>  target/mips/kvm.c      | 5 +++++
>  target/ppc/kvm.c       | 5 +++++
>  target/s390x/kvm/kvm.c | 5 +++++
>  7 files changed, 33 insertions(+)
> 
> diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
> index 27864dfaeaaa..a4bb449737a6 100644
> --- a/accel/kvm/kvm-all.c
> +++ b/accel/kvm/kvm-all.c
> @@ -465,6 +465,13 @@ int kvm_init_vcpu(CPUState *cpu, Error **errp)
>  
>      trace_kvm_init_vcpu(cpu->cpu_index, kvm_arch_vcpu_id(cpu));
>  
> +    ret = kvm_arch_pre_create_vcpu(cpu);
> +    if (ret < 0) {
> +        error_setg_errno(errp, -ret,
> +                         "kvm_init_vcpu: kvm_arch_pre_create_vcpu() failed");
> +        goto err;
> +    }
> +
>      ret = kvm_get_vcpu(s, kvm_arch_vcpu_id(cpu));
>      if (ret < 0) {
>          error_setg_errno(errp, -ret, "kvm_init_vcpu: kvm_get_vcpu failed 
> (%lu)",
> diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h
> index a783c7886811..0e94031ab7c7 100644
> --- a/include/sysemu/kvm.h
> +++ b/include/sysemu/kvm.h
> @@ -373,6 +373,7 @@ int kvm_arch_put_registers(CPUState *cpu, int level);
>  
>  int kvm_arch_init(MachineState *ms, KVMState *s);
>  
> +int kvm_arch_pre_create_vcpu(CPUState *cpu);
>  int kvm_arch_init_vcpu(CPUState *cpu);
>  int kvm_arch_destroy_vcpu(CPUState *cpu);
>  
> diff --git a/target/arm/kvm64.c b/target/arm/kvm64.c
> index ccadfbbe72be..ae7336851c62 100644
> --- a/target/arm/kvm64.c
> +++ b/target/arm/kvm64.c
> @@ -935,6 +935,11 @@ int kvm_arch_init_vcpu(CPUState *cs)
>      return kvm_arm_init_cpreg_list(cpu);
>  }
>  
> +int kvm_arch_pre_create_vcpu(CPUState *cpu)
> +{
> +    return 0;
> +}
> +

Weak symbol can be used to avoid update all the arch.

Thanks,
-- 
Isaku Yamahata <isaku.yamahata@gmail.com>