diff --git a/OvmfPkg/Include/Protocol/SevMemoryAcceptance.h b/OvmfPkg/Include/Protocol/SevMemoryAcceptance.h
new file mode 100644
index 0000000000..c5ea3f383a
--- /dev/null
+++ b/OvmfPkg/Include/Protocol/SevMemoryAcceptance.h
@@ -0,0 +1,43 @@
+/** @file
+  The file provides the protocol that disables the behavior that all memory
+  gets accepted at ExitBootServices(). This protocol is only meant to be called
+  by the OS loader, and not EDK2 itself. The SEV naming is due to the
+  coincidence that only SEV-SNP needs this protocol, since SEV-SNP Linux
+  support was released before it had support for unaccepted memory. The
+  technology enablement thus does not strictly imply support for the unaccepted
+  memory type.
+
+  Copyright (c) 2023, Google LLC. All rights reserved.<BR>
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+**/
+
+#ifndef SEV_MEMORY_ACCEPTANCE_H_
+#define SEV_MEMORY_ACCEPTANCE_H_
+
+#define OVMF_SEV_MEMORY_ACCEPTANCE_PROTOCOL_GUID \
+  {0xc5a010fe, \
+   0x38a7, \
+   0x4531, \
+   {0x8a, 0x4a, 0x05, 0x00, 0xd2, 0xfd, 0x16, 0x49}}
+
+typedef struct _OVMF_SEV_MEMORY_ACCEPTANCE_PROTOCOL
+    OVMF_SEV_MEMORY_ACCEPTANCE_PROTOCOL;
+
+/**
+  @param This A pointer to a OVMF_SEV_MEMORY_ACCEPTANCE_PROTOCOL.
+**/
+typedef
+  EFI_STATUS
+(EFIAPI *OVMF_SEV_ALLOW_UNACCEPTED_MEMORY)(
+  IN  OVMF_SEV_MEMORY_ACCEPTANCE_PROTOCOL  *This
+  );
+
+///
+/// The OVMF_SEV_MEMORY_ACCEPTANCE_PROTOCOL allows the OS loader to
+/// indicate to EDK2 that ExitBootServices should not accept all memory.
+///
+struct _OVMF_SEV_MEMORY_ACCEPTANCE_PROTOCOL {
+  OVMF_SEV_ALLOW_UNACCEPTED_MEMORY    AllowUnacceptedMemory;
+};
+
+#endif
diff --git a/OvmfPkg/OvmfPkg.dec b/OvmfPkg/OvmfPkg.dec
index 1b521f2604..a22eb246c6 100644
--- a/OvmfPkg/OvmfPkg.dec
+++ b/OvmfPkg/OvmfPkg.dec
@@ -184,6 +184,7 @@
   gEfiLegacyInterruptProtocolGuid       = {0x31ce593d, 0x108a, 0x485d, {0xad, 0xb2, 0x78, 0xf2, 0x1f, 0x29, 0x66, 0xbe}}
   gEfiVgaMiniPortProtocolGuid           = {0xc7735a2f, 0x88f5, 0x4882, {0xae, 0x63, 0xfa, 0xac, 0x8c, 0x8b, 0x86, 0xb3}}
   gOvmfLoadedX86LinuxKernelProtocolGuid = {0xa3edc05d, 0xb618, 0x4ff6, {0x95, 0x52, 0x76, 0xd7, 0x88, 0x63, 0x43, 0xc8}}
+  gOvmfSevMemoryAcceptanceProtocolGuid  = {0xc5a010fe, 0x38a7, 0x4531, {0x8a, 0x4a, 0x05, 0x00, 0xd2, 0xfd, 0x16, 0x49}}
   gQemuAcpiTableNotifyProtocolGuid      = {0x928939b2, 0x4235, 0x462f, {0x95, 0x80, 0xf6, 0xa2, 0xb2, 0xc2, 0x1a, 0x4f}}
   gEfiMpInitLibMpDepProtocolGuid        = {0xbb00a5ca, 0x8ce,  0x462f, {0xa5, 0x37, 0x43, 0xc7, 0x4a, 0x82, 0x5c, 0xa4}}
   gEfiMpInitLibUpDepProtocolGuid        = {0xa9e7cef1, 0x5682, 0x42cc, {0xb1, 0x23, 0x99, 0x30, 0x97, 0x3f, 0x4a, 0x9f}}