Re: [RFC PATCH v3 2/3] vmx: Introduce vcpu single context VPID invalidation

[Jan Beulich <jbeulich@xxxxxxxx>]

On 26.06.2025 16:01, Teddy Astie wrote:
> Introduce vpid_sync_vcpu_context to do a single-context invalidation
> on the vpid attached to the vcpu as a alternative to per-gva and all-context
> invlidations.
> 
> Signed-off-by: Teddy Astie <teddy.astie@xxxxxxxxxx>

Looks okay to me, but I'm not convinced we want to put it in possibly long
before a first user appears.

> --- a/xen/arch/x86/include/asm/hvm/vmx/vmx.h
> +++ b/xen/arch/x86/include/asm/hvm/vmx/vmx.h
> @@ -452,6 +452,19 @@ static inline void ept_sync_all(void)
>  
>  void ept_sync_domain(struct p2m_domain *p2m);
>  
> +static inline void vpid_sync_vcpu_context(struct vcpu *v)

Andrew - is this again a case where you would object to me asking for the
pointer to be pointer-to-const?

Jan

> +{
> +    unsigned long type;
> +
> +    /* Use the most precise invalidation type available. */
> +    if ( likely(cpu_has_vmx_vpid_invvpid_single_context) )
> +        type = INVVPID_SINGLE_CONTEXT;
> +    else
> +        type = INVVPID_ALL_CONTEXT;
> +
> +    __invvpid(type, v->arch.hvm.n1asid.asid, 0);
> +}
> +
>  static inline void vpid_sync_vcpu_gva(struct vcpu *v, unsigned long gva)
>  {
>      unsigned long type;