From d6586de12373a42e860afa25147a1d66a672f2e3 Mon Sep 17 00:00:00 2001
From: Hendrik Borghorst <hborghor@amazon.de>
Date: Tue, 6 Oct 2020 16:06:06 +0200
Subject: [PATCH] uefi: At least reserve 0xFFFF bytes for SMBios tables

We expect to soon have DMI v2 tables with longer SMBios tables. Allocate
0xFFFF (maximum of SMBios 2 tables) bytes so that no further change of
memory layout is necessary. This reduces the risk of hibernation
failures.

Signed-off-by: Hendrik Borghorst <hborghor@amazon.de>
Reviewed-by: Evgeny Iakovlev <eyakovl@amazon.de>
Reviewed-by: Alexander Graf (AWS) <graf@amazon.de>

diff --git a/MdeModulePkg/Universal/SmbiosDxe/SmbiosDxe.c b/MdeModulePkg/Universal/SmbiosDxe/SmbiosDxe.c
index 1d43adc766..8a392a8f56 100644
--- a/MdeModulePkg/Universal/SmbiosDxe/SmbiosDxe.c
+++ b/MdeModulePkg/Universal/SmbiosDxe/SmbiosDxe.c
@@ -1172,10 +1172,12 @@ SmbiosCreateTable (
     }
 
     PhysicalAddress = 0xffffffff;
+    // Allocate at least the 64 KiB
+    UINT32 AllocateSize = EntryPointStructure->TableLength <= 0xFFFF ? 0xFFFF : EntryPointStructure->TableLength;
     Status          = gBS->AllocatePages (
                              AllocateMaxAddress,
                              EfiRuntimeServicesData,
-                             EFI_SIZE_TO_PAGES (EntryPointStructure->TableLength),
+                             EFI_SIZE_TO_PAGES (AllocateSize),
                              &PhysicalAddress
                              );
     if (EFI_ERROR (Status)) {
@@ -1184,7 +1186,7 @@ SmbiosCreateTable (
       return EFI_OUT_OF_RESOURCES;
     } else {
       EntryPointStructure->TableAddress = (UINT32)PhysicalAddress;
-      mPreAllocatedPages                = EFI_SIZE_TO_PAGES (EntryPointStructure->TableLength);
+      mPreAllocatedPages                = EFI_SIZE_TO_PAGES (AllocateSize);
     }
   }