It is essential for TD users to be aware of the vendor and version of
the current TDX. Additionally, they can reference the TDX version when
reporting bugs or issues.
Furthermore, the applications or device drivers running in TD can achieve
enhanced reliability and flexibility by following the TDX Module ABI
specification, because there are significant differences between different
versions of TDX, as mentioned in the "Intel® TDX Module Incompatibilities
between v1.0 and v1.5" reference. Here are a few examples:
MSR Name Index Reason
----------------------------------------------
IA32_UARCH_MISC_CTL 0x1B01 From v1.5
IA32_ARCH_CAPABILITIES 0x010A Changed in v1.5
IA32_TSX_CTRL 0x0122 Changed in v1.5
CPUID Leaf Sub-leaf Reason
---------------------------------------
0x7 2 From v1.5
0x22 0 From v1.5
0x23 0~3 From v1.5
0x80000007 0 From v1.5
During TD initialization, the TDX version info can be obtained by calling
TDG.SYS.RD. This will fetch the current version of TDX, including the major
and minor version numbers and vendor ID.
The TDCALL TDG.SYS.RD originates from TDX version 1.5. If the error
TDCALL_INVALID_OPERAND occurs, it should be treated as TDX version 1.0.
Co-developed-by: Dongcheng Yan <[email protected]>
Signed-off-by: Dongcheng Yan <[email protected]>
Signed-off-by: Yi Sun <[email protected]>
diff --git a/arch/x86/coco/tdx/tdx.c b/arch/x86/coco/tdx/tdx.c
index 1d6b863c42b0..0f51123aa0b9 100644
--- a/arch/x86/coco/tdx/tdx.c
+++ b/arch/x86/coco/tdx/tdx.c
@@ -37,6 +37,27 @@
#define TDREPORT_SUBTYPE_0 0
+/*
+ * TDX metadata base field id, used by TDCALL TDG.SYS.RD
+ * See TDX ABI Spec section 3.3.2.3 Global Metadata Fields
+ */
+#define TDX_SYS_VENDOR_ID_FID 0x0800000200000000ULL
+#define TDX_SYS_MINOR_FID 0x0800000100000003ULL
+#define TDX_SYS_MAJOR_FID 0x0800000100000004ULL
+#define TDX_VENDOR_INTEL 0x8086
+
+struct tdg_sys_info {
+ u32 vendor_id;
+ u16 major_version;
+ u16 minor_version;
+};
+
+/*
+ * Fetch TDX Module global-scope metadata field via TDG.SYS.RD TDCALL
+ * Do NOT change it once initialized.
+ */
+static struct tdg_sys_info td_sys_info;
+
/* Called from __tdx_hypercall() for unrecoverable failure */
noinstr void __tdx_hypercall_failed(void)
{
@@ -757,6 +778,46 @@ static bool tdx_enc_status_change_finish(unsigned long vaddr, int numpages,
return true;
}
+/*
+ * Parse the tdx module version info from the global-scope metadata fields.
+ */
+static int tdg_get_sysinfo(void)
+{
+ struct tdx_module_output out;
+ u64 ret;
+
+ ret = __tdx_module_call(TDX_SYS_RD, 0, TDX_SYS_VENDOR_ID_FID, 0, 0,
+ &out);
+ if (TDCALL_RETURN_CODE(ret) == TDCALL_INVALID_OPERAND)
+ goto version_1_0;
+ else if (ret)
+ return ret;
+
+ td_sys_info.vendor_id = (u32)(out).r8;
+
+ ret = __tdx_module_call(TDX_SYS_RD, 0, TDX_SYS_MAJOR_FID, 0, 0, &out);
+ if (ret)
+ return ret;
+
+ td_sys_info.major_version = (u16)(out).r8;
+
+ ret = __tdx_module_call(TDX_SYS_RD, 0, TDX_SYS_MINOR_FID, 0, 0, &out);
+ if (ret)
+ return ret;
+
+ td_sys_info.minor_version = (u16)(out).r8;
+
+ return 0;
+
+ /* TDX 1.0 does not have the TDCALL TDG.SYS.RD */
+version_1_0:
+ td_sys_info.vendor_id = TDX_VENDOR_INTEL;
+ td_sys_info.major_version = 1;
+ td_sys_info.minor_version = 0;
+
+ return 0;
+}
+
void __init tdx_early_init(void)
{
u64 cc_mask;
@@ -820,5 +881,9 @@ void __init tdx_early_init(void)
*/
x86_cpuinit.parallel_bringup = false;
- pr_info("Guest detected\n");
+ tdg_get_sysinfo();
+
+ pr_info("Guest detected. TDX version:%u.%u VendorID: %x\n",
+ td_sys_info.major_version, td_sys_info.minor_version,
+ td_sys_info.vendor_id);
}
diff --git a/arch/x86/include/asm/shared/tdx.h b/arch/x86/include/asm/shared/tdx.h
index 7513b3bb69b7..10ecb5dece84 100644
--- a/arch/x86/include/asm/shared/tdx.h
+++ b/arch/x86/include/asm/shared/tdx.h
@@ -16,6 +16,7 @@
#define TDX_GET_REPORT 4
#define TDX_ACCEPT_PAGE 6
#define TDX_WR 8
+#define TDX_SYS_RD 11
/* TDCS fields. To be used by TDG.VM.WR and TDG.VM.RD module calls */
#define TDCS_NOTIFY_ENABLES 0x9100000000000010
--
2.34.1
On Fri, Sep 22, 2023 at 04:03:22PM +0800, Yi Sun wrote:
> It is essential for TD users to be aware of the vendor and version of
> the current TDX. Additionally, they can reference the TDX version when
> reporting bugs or issues.
>
> Furthermore, the applications or device drivers running in TD can achieve
> enhanced reliability and flexibility by following the TDX Module ABI
> specification, because there are significant differences between different
> versions of TDX, as mentioned in the "Intel? TDX Module Incompatibilities
> between v1.0 and v1.5" reference. Here are a few examples:
>
> MSR Name Index Reason
> ----------------------------------------------
> IA32_UARCH_MISC_CTL 0x1B01 From v1.5
> IA32_ARCH_CAPABILITIES 0x010A Changed in v1.5
> IA32_TSX_CTRL 0x0122 Changed in v1.5
>
> CPUID Leaf Sub-leaf Reason
> ---------------------------------------
> 0x7 2 From v1.5
> 0x22 0 From v1.5
> 0x23 0~3 From v1.5
> 0x80000007 0 From v1.5
>
> During TD initialization, the TDX version info can be obtained by calling
> TDG.SYS.RD. This will fetch the current version of TDX, including the major
> and minor version numbers and vendor ID.
>
> The TDCALL TDG.SYS.RD originates from TDX version 1.5. If the error
> TDCALL_INVALID_OPERAND occurs, it should be treated as TDX version 1.0.
>
> Co-developed-by: Dongcheng Yan <[email protected]>
> Signed-off-by: Dongcheng Yan <[email protected]>
> Signed-off-by: Yi Sun <[email protected]>
>
> diff --git a/arch/x86/coco/tdx/tdx.c b/arch/x86/coco/tdx/tdx.c
> index 1d6b863c42b0..0f51123aa0b9 100644
> --- a/arch/x86/coco/tdx/tdx.c
> +++ b/arch/x86/coco/tdx/tdx.c
> @@ -37,6 +37,27 @@
>
> #define TDREPORT_SUBTYPE_0 0
>
> +/*
> + * TDX metadata base field id, used by TDCALL TDG.SYS.RD
> + * See TDX ABI Spec section 3.3.2.3 Global Metadata Fields
> + */
> +#define TDX_SYS_VENDOR_ID_FID 0x0800000200000000ULL
> +#define TDX_SYS_MINOR_FID 0x0800000100000003ULL
> +#define TDX_SYS_MAJOR_FID 0x0800000100000004ULL
> +#define TDX_VENDOR_INTEL 0x8086
> +
> +struct tdg_sys_info {
> + u32 vendor_id;
> + u16 major_version;
> + u16 minor_version;
> +};
> +
> +/*
> + * Fetch TDX Module global-scope metadata field via TDG.SYS.RD TDCALL
> + * Do NOT change it once initialized.
> + */
> +static struct tdg_sys_info td_sys_info;
> +
Why here?
I think we can allocate on stack inside tdx_early_init() and pass down to
tdg_get_sysinfo() to fill. The variable is not needed after
tdx_early_init() returns.
--
Kiryl Shutsemau / Kirill A. Shutemov