On Thu, 19 Mar 2020, Joerg Roedel wrote:

> From: Tom Lendacky <thomas.lenda...@amd.com>
> 
> Implement the callbacks to copy the processor state required by KVM to
> the GHCB.
> 
> Signed-off-by: Tom Lendacky <thomas.lenda...@amd.com>
> [ jroe...@suse.de: - Split out of a larger patch
>                    - Adapt to different callback functions ]
> Co-developed-by: Joerg Roedel <jroe...@suse.de>
> Signed-off-by: Joerg Roedel <jroe...@suse.de>
> ---
>  arch/x86/kernel/kvm.c | 35 +++++++++++++++++++++++++++++------
>  1 file changed, 29 insertions(+), 6 deletions(-)
> 
> diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
> index 6efe0410fb72..0e3fc798d719 100644
> --- a/arch/x86/kernel/kvm.c
> +++ b/arch/x86/kernel/kvm.c
> @@ -34,6 +34,8 @@
>  #include <asm/hypervisor.h>
>  #include <asm/tlb.h>
>  #include <asm/cpuidle_haltpoll.h>
> +#include <asm/ptrace.h>
> +#include <asm/svm.h>
>  
>  static int kvmapf = 1;
>  
> @@ -729,13 +731,34 @@ static void __init kvm_init_platform(void)
>       x86_platform.apic_post_init = kvm_apic_init;
>  }
>  
> +#if defined(CONFIG_AMD_MEM_ENCRYPT)
> +static void kvm_sev_es_hcall_prepare(struct ghcb *ghcb, struct pt_regs *regs)
> +{
> +     /* RAX and CPL are already in the GHCB */
> +     ghcb_set_rbx(ghcb, regs->bx);
> +     ghcb_set_rcx(ghcb, regs->cx);
> +     ghcb_set_rdx(ghcb, regs->dx);
> +     ghcb_set_rsi(ghcb, regs->si);

Is it possible to check the hypercall from RAX and only copy the needed 
regs or is there a requirement that they must all be copied 
unconditionally?

> +}
> +
> +static bool kvm_sev_es_hcall_finish(struct ghcb *ghcb, struct pt_regs *regs)
> +{
> +     /* No checking of the return state needed */
> +     return true;
> +}
> +#endif
> +
>  const __initconst struct hypervisor_x86 x86_hyper_kvm = {
> -     .name                   = "KVM",
> -     .detect                 = kvm_detect,
> -     .type                   = X86_HYPER_KVM,
> -     .init.guest_late_init   = kvm_guest_init,
> -     .init.x2apic_available  = kvm_para_available,
> -     .init.init_platform     = kvm_init_platform,
> +     .name                           = "KVM",
> +     .detect                         = kvm_detect,
> +     .type                           = X86_HYPER_KVM,
> +     .init.guest_late_init           = kvm_guest_init,
> +     .init.x2apic_available          = kvm_para_available,
> +     .init.init_platform             = kvm_init_platform,
> +#if defined(CONFIG_AMD_MEM_ENCRYPT)
> +     .runtime.sev_es_hcall_prepare   = kvm_sev_es_hcall_prepare,
> +     .runtime.sev_es_hcall_finish    = kvm_sev_es_hcall_finish,
> +#endif
>  };
>  
>  static __init int activate_jump_labels(void)
> -- 
> 2.17.1
> 
> 
_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization

Reply via email to