Merge tag 'x86_tdx_for_6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 TDX updates from Dave Hansen:
 "This contains the initial support for host-side TDX support so that
  KVM can run TDX-protected guests. This does not include the actual
  KVM-side support which will come from the KVM folks. The TDX host
  interactions with kexec also needs to be ironed out before this is
  ready for prime time, so this code is currently Kconfig'd off when
  kexec is on.

  The majority of the code here is the kernel telling the TDX module
  which memory to protect and handing some additional memory over to it
  to use to store TDX module metadata. That sounds pretty simple, but
  the TDX architecture is rather flexible and it takes quite a bit of
  back-and-forth to say, "just protect all memory, please."

  There is also some code tacked on near the end of the series to handle
  a hardware erratum. The erratum can make software bugs such as a
  kernel write to TDX-protected memory cause a machine check and
  masquerade as a real hardware failure. The erratum handling watches
  out for these and tries to provide nicer user errors"

* tag 'x86_tdx_for_6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits)
  x86/virt/tdx: Make TDX host depend on X86_MCE
  x86/virt/tdx: Disable TDX host support when kexec is enabled
  Documentation/x86: Add documentation for TDX host support
  x86/mce: Differentiate real hardware #MCs from TDX erratum ones
  x86/cpu: Detect TDX partial write machine check erratum
  x86/virt/tdx: Handle TDX interaction with sleep and hibernation
  x86/virt/tdx: Initialize all TDMRs
  x86/virt/tdx: Configure global KeyID on all packages
  x86/virt/tdx: Configure TDX module with the TDMRs and global KeyID
  x86/virt/tdx: Designate reserved areas for all TDMRs
  x86/virt/tdx: Allocate and set up PAMTs for TDMRs
  x86/virt/tdx: Fill out TDMRs to cover all TDX memory regions
  x86/virt/tdx: Add placeholder to construct TDMRs to cover all TDX memory regions
  x86/virt/tdx: Get module global metadata for module initialization
  x86/virt/tdx: Use all system memory when initializing TDX module as TDX memory
  x86/virt/tdx: Add skeleton to enable TDX on demand
  x86/virt/tdx: Add SEAMCALL error printing for module initialization
  x86/virt/tdx: Handle SEAMCALL no entropy error in common code
  x86/virt/tdx: Make INTEL_TDX_HOST depend on X86_X2APIC
  x86/virt/tdx: Define TDX supported page sizes as macros
  ...

1 files changed, 121 insertions, 0 deletions

diff --git a/arch/x86/virt/vmx/tdx/tdx.h b/arch/x86/virt/vmx/tdx/tdx.h
new file mode 100644
index 000000000000..b701f69485d3
--- /dev/null
+++ b/arch/x86/virt/vmx/tdx/tdx.h
@@ -0,0 +1,121 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _X86_VIRT_TDX_H
+#define _X86_VIRT_TDX_H
+
+#include <linux/bits.h>
+
+/*
+ * This file contains both macros and data structures defined by the TDX
+ * architecture and Linux defined software data structures and functions.
+ * The two should not be mixed together for better readability.  The
+ * architectural definitions come first.
+ */
+
+/*
+ * TDX module SEAMCALL leaf functions
+ */
+#define TDH_PHYMEM_PAGE_RDMD	24
+#define TDH_SYS_KEY_CONFIG	31
+#define TDH_SYS_INIT		33
+#define TDH_SYS_RD		34
+#define TDH_SYS_LP_INIT		35
+#define TDH_SYS_TDMR_INIT	36
+#define TDH_SYS_CONFIG		45
+
+/* TDX page types */
+#define	PT_NDA		0x0
+#define	PT_RSVD		0x1
+
+/*
+ * Global scope metadata field ID.
+ *
+ * See Table "Global Scope Metadata", TDX module 1.5 ABI spec.
+ */
+#define MD_FIELD_ID_MAX_TDMRS			0x9100000100000008ULL
+#define MD_FIELD_ID_MAX_RESERVED_PER_TDMR	0x9100000100000009ULL
+#define MD_FIELD_ID_PAMT_4K_ENTRY_SIZE		0x9100000100000010ULL
+#define MD_FIELD_ID_PAMT_2M_ENTRY_SIZE		0x9100000100000011ULL
+#define MD_FIELD_ID_PAMT_1G_ENTRY_SIZE		0x9100000100000012ULL
+
+/*
+ * Sub-field definition of metadata field ID.
+ *
+ * See Table "MD_FIELD_ID (Metadata Field Identifier / Sequence Header)
+ * Definition", TDX module 1.5 ABI spec.
+ *
+ *  - Bit 33:32: ELEMENT_SIZE_CODE -- size of a single element of metadata
+ *
+ *	0: 8 bits
+ *	1: 16 bits
+ *	2: 32 bits
+ *	3: 64 bits
+ */
+#define MD_FIELD_ID_ELE_SIZE_CODE(_field_id)	\
+		(((_field_id) & GENMASK_ULL(33, 32)) >> 32)
+
+#define MD_FIELD_ID_ELE_SIZE_16BIT	1
+
+struct tdmr_reserved_area {
+	u64 offset;
+	u64 size;
+} __packed;
+
+#define TDMR_INFO_ALIGNMENT	512
+#define TDMR_INFO_PA_ARRAY_ALIGNMENT	512
+
+struct tdmr_info {
+	u64 base;
+	u64 size;
+	u64 pamt_1g_base;
+	u64 pamt_1g_size;
+	u64 pamt_2m_base;
+	u64 pamt_2m_size;
+	u64 pamt_4k_base;
+	u64 pamt_4k_size;
+	/*
+	 * The actual number of reserved areas depends on the value of
+	 * field MD_FIELD_ID_MAX_RESERVED_PER_TDMR in the TDX module
+	 * global metadata.
+	 */
+	DECLARE_FLEX_ARRAY(struct tdmr_reserved_area, reserved_areas);
+} __packed __aligned(TDMR_INFO_ALIGNMENT);
+
+/*
+ * Do not put any hardware-defined TDX structure representations below
+ * this comment!
+ */
+
+/* Kernel defined TDX module status during module initialization. */
+enum tdx_module_status_t {
+	TDX_MODULE_UNINITIALIZED,
+	TDX_MODULE_INITIALIZED,
+	TDX_MODULE_ERROR
+};
+
+struct tdx_memblock {
+	struct list_head list;
+	unsigned long start_pfn;
+	unsigned long end_pfn;
+	int nid;
+};
+
+/* "TDMR info" part of "Global Scope Metadata" for constructing TDMRs */
+struct tdx_tdmr_sysinfo {
+	u16 max_tdmrs;
+	u16 max_reserved_per_tdmr;
+	u16 pamt_entry_size[TDX_PS_NR];
+};
+
+/* Warn if kernel has less than TDMR_NR_WARN TDMRs after allocation */
+#define TDMR_NR_WARN 4
+
+struct tdmr_info_list {
+	void *tdmrs;	/* Flexible array to hold 'tdmr_info's */
+	int nr_consumed_tdmrs;	/* How many 'tdmr_info's are in use */
+
+	/* Metadata for finding target 'tdmr_info' and freeing @tdmrs */
+	int tdmr_sz;	/* Size of one 'tdmr_info' */
+	int max_tdmrs;	/* How many 'tdmr_info's are allocated */
+};
+
+#endif