On Thu, Jun 03, 2021 at 03:14:37PM +0000, Vineeth Pillai wrote:
> SVM added support for certain reserved fields to be used by
> software or hypervisor. Add the following reserved fields:
> - VMCB offset 0x3e0 - 0x3ff
> - Clean bit 31
> - SVM intercept exit code 0xf0000000
>
> Later patches will make use of this for supporting Hyper-V
> nested virtualization enhancements.
>
> Signed-off-by: Vineeth Pillai <viremana@xxxxxxxxxxxxxxxxxxx>
> ---
> arch/x86/include/asm/svm.h | 9 +++++++--
> arch/x86/include/uapi/asm/svm.h | 3 +++
> arch/x86/kvm/svm/svm.h | 17 +++++++++++++++--
> 3 files changed, 25 insertions(+), 4 deletions(-)
>
> diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h
> index 772e60efe243..e322676039f4 100644
> --- a/arch/x86/include/asm/svm.h
> +++ b/arch/x86/include/asm/svm.h
> @@ -156,6 +156,12 @@ struct __attribute__ ((__packed__)) vmcb_control_area {
> u64 avic_physical_id; /* Offset 0xf8 */
> u8 reserved_7[8];
> u64 vmsa_pa; /* Used for an SEV-ES guest */
> + u8 reserved_8[720];
> + /*
> + * Offset 0x3e0, 32 bytes reserved
> + * for use by hypervisor/software.
> + */
> + u8 reserved_sw[32];
> };
>
>
> @@ -314,7 +320,7 @@ struct ghcb {
>
>
> #define EXPECTED_VMCB_SAVE_AREA_SIZE 1032
> -#define EXPECTED_VMCB_CONTROL_AREA_SIZE 272
> +#define EXPECTED_VMCB_CONTROL_AREA_SIZE 1024
> #define EXPECTED_GHCB_SIZE PAGE_SIZE
>
> static inline void __unused_size_checks(void)
> @@ -326,7 +332,6 @@ static inline void __unused_size_checks(void)
>
> struct vmcb {
> struct vmcb_control_area control;
> - u8 reserved_control[1024 - sizeof(struct vmcb_control_area)];
> struct vmcb_save_area save;
> } __packed;
>
> diff --git a/arch/x86/include/uapi/asm/svm.h b/arch/x86/include/uapi/asm/svm.h
> index 554f75fe013c..efa969325ede 100644
> --- a/arch/x86/include/uapi/asm/svm.h
> +++ b/arch/x86/include/uapi/asm/svm.h
> @@ -110,6 +110,9 @@
> #define SVM_VMGEXIT_GET_AP_JUMP_TABLE 1
> #define SVM_VMGEXIT_UNSUPPORTED_EVENT 0x8000ffff
>
> +/* Exit code reserved for hypervisor/software use */
> +#define SVM_EXIT_SW 0xf0000000
Apologies for reviving this 2021 thread, but it seems like the APM says
in Table C-1. SVM Intercept Codes that the host reserved value is
F000_000h.
APM typo or wrong KVM definition?
