Merge tag 'x86_cc_for_v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 confidential computing update from Borislav Petkov:

 - Add support for unaccepted memory as specified in the UEFI spec v2.9.

   The gist of it all is that Intel TDX and AMD SEV-SNP confidential
   computing guests define the notion of accepting memory before using
   it and thus preventing a whole set of attacks against such guests
   like memory replay and the like.

   There are a couple of strategies of how memory should be accepted -
   the current implementation does an on-demand way of accepting.

* tag 'x86_cc_for_v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  virt: sevguest: Add CONFIG_CRYPTO dependency
  x86/efi: Safely enable unaccepted memory in UEFI
  x86/sev: Add SNP-specific unaccepted memory support
  x86/sev: Use large PSC requests if applicable
  x86/sev: Allow for use of the early boot GHCB for PSC requests
  x86/sev: Put PSC struct on the stack in prep for unaccepted memory support
  x86/sev: Fix calculation of end address based on number of pages
  x86/tdx: Add unaccepted memory support
  x86/tdx: Refactor try_accept_one()
  x86/tdx: Make _tdx_hypercall() and __tdx_module_call() available in boot stub
  efi/unaccepted: Avoid load_unaligned_zeropad() stepping into unaccepted memory
  efi: Add unaccepted memory support
  x86/boot/compressed: Handle unaccepted memory
  efi/libstub: Implement support for unaccepted memory
  efi/x86: Get full memory map in allocate_e820()
  mm: Add support for unaccepted memory

6 files changed, 106 insertions, 29 deletions

diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
index 419280d263d2..8b4be7cecdb8 100644
--- a/arch/x86/include/asm/efi.h
+++ b/arch/x86/include/asm/efi.h
@@ -31,6 +31,8 @@ extern unsigned long efi_mixed_mode_stack_pa;
 
 #define ARCH_EFI_IRQ_FLAGS_MASK	X86_EFLAGS_IF
 
+#define EFI_UNACCEPTED_UNIT_SIZE PMD_SIZE
+
 /*
  * The EFI services are called through variadic functions in many cases. These
  * functions are implemented in assembler and support only a fixed number of
diff --git a/arch/x86/include/asm/sev-common.h b/arch/x86/include/asm/sev-common.h
index 0759af9b1acf..b463fcbd4b90 100644
--- a/arch/x86/include/asm/sev-common.h
+++ b/arch/x86/include/asm/sev-common.h
@@ -106,8 +106,13 @@ enum psc_op {
 #define GHCB_HV_FT_SNP			BIT_ULL(0)
 #define GHCB_HV_FT_SNP_AP_CREATION	BIT_ULL(1)
 
-/* SNP Page State Change NAE event */
-#define VMGEXIT_PSC_MAX_ENTRY		253
+/*
+ * SNP Page State Change NAE event
+ *   The VMGEXIT_PSC_MAX_ENTRY determines the size of the PSC structure, which
+ *   is a local stack variable in set_pages_state(). Do not increase this value
+ *   without evaluating the impact to stack usage.
+ */
+#define VMGEXIT_PSC_MAX_ENTRY		64
 
 struct psc_hdr {
 	u16 cur_entry;
diff --git a/arch/x86/include/asm/sev.h b/arch/x86/include/asm/sev.h
index 13dc2a9d23c1..86e1296e87f5 100644
--- a/arch/x86/include/asm/sev.h
+++ b/arch/x86/include/asm/sev.h
@@ -80,11 +80,15 @@ extern void vc_no_ghcb(void);
 extern void vc_boot_ghcb(void);
 extern bool handle_vc_boot_ghcb(struct pt_regs *regs);
 
+/* PVALIDATE return codes */
+#define PVALIDATE_FAIL_SIZEMISMATCH	6
+
 /* Software defined (when rFlags.CF = 1) */
 #define PVALIDATE_FAIL_NOUPDATE		255
 
 /* RMP page size */
 #define RMP_PG_SIZE_4K			0
+#define RMP_PG_SIZE_2M			1
 
 #define RMPADJUST_VMSA_PAGE_BIT		BIT(16)
 
@@ -192,16 +196,17 @@ struct snp_guest_request_ioctl;
 
 void setup_ghcb(void);
 void __init early_snp_set_memory_private(unsigned long vaddr, unsigned long paddr,
-					 unsigned int npages);
+					 unsigned long npages);
 void __init early_snp_set_memory_shared(unsigned long vaddr, unsigned long paddr,
-					unsigned int npages);
+					unsigned long npages);
 void __init snp_prep_memory(unsigned long paddr, unsigned int sz, enum psc_op op);
-void snp_set_memory_shared(unsigned long vaddr, unsigned int npages);
-void snp_set_memory_private(unsigned long vaddr, unsigned int npages);
+void snp_set_memory_shared(unsigned long vaddr, unsigned long npages);
+void snp_set_memory_private(unsigned long vaddr, unsigned long npages);
 void snp_set_wakeup_secondary_cpu(void);
 bool snp_init(struct boot_params *bp);
 void __init __noreturn snp_abort(void);
 int snp_issue_guest_request(u64 exit_code, struct snp_req_data *input, struct snp_guest_request_ioctl *rio);
+void snp_accept_memory(phys_addr_t start, phys_addr_t end);
 #else
 static inline void sev_es_ist_enter(struct pt_regs *regs) { }
 static inline void sev_es_ist_exit(void) { }
@@ -212,12 +217,12 @@ static inline int pvalidate(unsigned long vaddr, bool rmp_psize, bool validate)
 static inline int rmpadjust(unsigned long vaddr, bool rmp_psize, unsigned long attrs) { return 0; }
 static inline void setup_ghcb(void) { }
 static inline void __init
-early_snp_set_memory_private(unsigned long vaddr, unsigned long paddr, unsigned int npages) { }
+early_snp_set_memory_private(unsigned long vaddr, unsigned long paddr, unsigned long npages) { }
 static inline void __init
-early_snp_set_memory_shared(unsigned long vaddr, unsigned long paddr, unsigned int npages) { }
+early_snp_set_memory_shared(unsigned long vaddr, unsigned long paddr, unsigned long npages) { }
 static inline void __init snp_prep_memory(unsigned long paddr, unsigned int sz, enum psc_op op) { }
-static inline void snp_set_memory_shared(unsigned long vaddr, unsigned int npages) { }
-static inline void snp_set_memory_private(unsigned long vaddr, unsigned int npages) { }
+static inline void snp_set_memory_shared(unsigned long vaddr, unsigned long npages) { }
+static inline void snp_set_memory_private(unsigned long vaddr, unsigned long npages) { }
 static inline void snp_set_wakeup_secondary_cpu(void) { }
 static inline bool snp_init(struct boot_params *bp) { return false; }
 static inline void snp_abort(void) { }
@@ -225,6 +230,8 @@ static inline int snp_issue_guest_request(u64 exit_code, struct snp_req_data *in
 {
 	return -ENOTTY;
 }
+
+static inline void snp_accept_memory(phys_addr_t start, phys_addr_t end) { }
 #endif
 
 #endif
diff --git a/arch/x86/include/asm/shared/tdx.h b/arch/x86/include/asm/shared/tdx.h
index 2631e01f6e0f..19228beb4894 100644
--- a/arch/x86/include/asm/shared/tdx.h
+++ b/arch/x86/include/asm/shared/tdx.h
@@ -10,6 +10,20 @@
 #define TDX_CPUID_LEAF_ID	0x21
 #define TDX_IDENT		"IntelTDX    "
 
+/* TDX module Call Leaf IDs */
+#define TDX_GET_INFO			1
+#define TDX_GET_VEINFO			3
+#define TDX_GET_REPORT			4
+#define TDX_ACCEPT_PAGE			6
+#define TDX_WR				8
+
+/* TDCS fields. To be used by TDG.VM.WR and TDG.VM.RD module calls */
+#define TDCS_NOTIFY_ENABLES		0x9100000000000010
+
+/* TDX hypercall Leaf IDs */
+#define TDVMCALL_MAP_GPA		0x10001
+#define TDVMCALL_REPORT_FATAL_ERROR	0x10003
+
 #ifndef __ASSEMBLY__
 
 /*
@@ -37,8 +51,47 @@ struct tdx_hypercall_args {
 u64 __tdx_hypercall(struct tdx_hypercall_args *args);
 u64 __tdx_hypercall_ret(struct tdx_hypercall_args *args);
 
+/*
+ * Wrapper for standard use of __tdx_hypercall with no output aside from
+ * return code.
+ */
+static inline u64 _tdx_hypercall(u64 fn, u64 r12, u64 r13, u64 r14, u64 r15)
+{
+	struct tdx_hypercall_args args = {
+		.r10 = TDX_HYPERCALL_STANDARD,
+		.r11 = fn,
+		.r12 = r12,
+		.r13 = r13,
+		.r14 = r14,
+		.r15 = r15,
+	};
+
+	return __tdx_hypercall(&args);
+}
+
+
 /* Called from __tdx_hypercall() for unrecoverable failure */
 void __tdx_hypercall_failed(void);
 
+/*
+ * Used in __tdx_module_call() to gather the output registers' values of the
+ * TDCALL instruction when requesting services from the TDX module. This is a
+ * software only structure and not part of the TDX module/VMM ABI
+ */
+struct tdx_module_output {
+	u64 rcx;
+	u64 rdx;
+	u64 r8;
+	u64 r9;
+	u64 r10;
+	u64 r11;
+};
+
+/* Used to communicate with the TDX module */
+u64 __tdx_module_call(u64 fn, u64 rcx, u64 rdx, u64 r8, u64 r9,
+		      struct tdx_module_output *out);
+
+bool tdx_accept_memory(phys_addr_t start, phys_addr_t end);
+
 #endif /* !__ASSEMBLY__ */
 #endif /* _ASM_X86_SHARED_TDX_H */
diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
index 28d889c9aa16..603e6d1e9d4a 100644
--- a/arch/x86/include/asm/tdx.h
+++ b/arch/x86/include/asm/tdx.h
@@ -5,6 +5,8 @@
 
 #include <linux/init.h>
 #include <linux/bits.h>
+
+#include <asm/errno.h>
 #include <asm/ptrace.h>
 #include <asm/shared/tdx.h>
 
@@ -21,21 +23,6 @@
 #ifndef __ASSEMBLY__
 
 /*
- * Used to gather the output registers values of the TDCALL and SEAMCALL
- * instructions when requesting services from the TDX module.
- *
- * This is a software only structure and not part of the TDX module/VMM ABI.
- */
-struct tdx_module_output {
-	u64 rcx;
-	u64 rdx;
-	u64 r8;
-	u64 r9;
-	u64 r10;
-	u64 r11;
-};
-
-/*
  * Used by the #VE exception handler to gather the #VE exception
  * info from the TDX module. This is a software only structure
  * and not part of the TDX module/VMM ABI.
@@ -55,10 +42,6 @@ struct ve_info {
 
 void __init tdx_early_init(void);
 
-/* Used to communicate with the TDX module */
-u64 __tdx_module_call(u64 fn, u64 rcx, u64 rdx, u64 r8, u64 r9,
-		      struct tdx_module_output *out);
-
 void tdx_get_ve_info(struct ve_info *ve);
 
 bool tdx_handle_virt_exception(struct pt_regs *regs, struct ve_info *ve);
diff --git a/arch/x86/include/asm/unaccepted_memory.h b/arch/x86/include/asm/unaccepted_memory.h
new file mode 100644
index 000000000000..f5937e9866ac
--- /dev/null
+++ b/arch/x86/include/asm/unaccepted_memory.h
@@ -0,0 +1,27 @@
+#ifndef _ASM_X86_UNACCEPTED_MEMORY_H
+#define _ASM_X86_UNACCEPTED_MEMORY_H
+
+#include <linux/efi.h>
+#include <asm/tdx.h>
+#include <asm/sev.h>
+
+static inline void arch_accept_memory(phys_addr_t start, phys_addr_t end)
+{
+	/* Platform-specific memory-acceptance call goes here */
+	if (cpu_feature_enabled(X86_FEATURE_TDX_GUEST)) {
+		if (!tdx_accept_memory(start, end))
+			panic("TDX: Failed to accept memory\n");
+	} else if (cc_platform_has(CC_ATTR_GUEST_SEV_SNP)) {
+		snp_accept_memory(start, end);
+	} else {
+		panic("Cannot accept memory: unknown platform\n");
+	}
+}
+
+static inline struct efi_unaccepted_memory *efi_get_unaccepted_table(void)
+{
+	if (efi.unaccepted == EFI_INVALID_TABLE_ADDR)
+		return NULL;
+	return __va(efi.unaccepted);
+}
+#endif