1 files changed, 54 insertions, 0 deletions
diff --git a/OvmfPkg/Library/MemDebugLogLib/MemDebugLogRt.c b/OvmfPkg/Library/MemDebugLogLib/MemDebugLogRt.c
new file mode 100644
index 0000000..456bb70
--- /dev/null
+++ b/OvmfPkg/Library/MemDebugLogLib/MemDebugLogRt.c
@@ -0,0 +1,54 @@
+/** @file
+ *
+  Memory Debug Log Library - Runtime
+
+  Copyright (C) 2025, Oracle and/or its affiliates.
+
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+**/
+
+#include <PiDxe.h>
+#include <Library/MemDebugLogLib.h>
+#include <Library/UefiRuntimeLib.h>
+
+EFI_PHYSICAL_ADDRESS  mMemDebugLogBufAddr;
+BOOLEAN               mMemDebugLogBufAddrInit;
+
+EFI_STATUS
+EFIAPI
+MemDebugLogWrite (
+  IN  CHAR8  *Buffer,
+  IN  UINTN  Length
+  )
+{
+  EFI_STATUS  Status;
+
+  //
+  // Stop logging after we have switched to virtual mode
+  // to avoid potential problems (such as crashes accessing
+  // physical pointers).
+  //
+  if (EfiGoneVirtual ()) {
+    return EFI_SUCCESS;
+  }
+
+  if (!mMemDebugLogBufAddrInit) {
+    //
+    // Obtain the Memory Debug Log buffer addr from HOB
+    //
+    Status = MemDebugLogAddrFromHOB (&mMemDebugLogBufAddr);
+    if (EFI_ERROR (Status)) {
+      mMemDebugLogBufAddr = 0;
+    }
+
+    mMemDebugLogBufAddrInit = TRUE;
+  }
+
+  if (mMemDebugLogBufAddr) {
+    Status = MemDebugLogWriteBuffer (mMemDebugLogBufAddr, Buffer, Length);
+  } else {
+    Status = EFI_NOT_FOUND;
+  }
+
+  return Status;
+}