From 9ff9bd81c4259db3e027999dd5c05341ffaa9b4e Mon Sep 17 00:00:00 2001
From: Serge Gautherie <reactos-git_serge_171003@gautherie.fr>
Date: Sat, 3 Feb 2018 00:19:18 +0100
Subject: [PATCH] [NTOSKRNL] Round memory size up, "debug log" part

Assumed to better match actual physical RAM size.

CORE-12321
---
 ntoskrnl/ex/init.c     | 5 +++--
 ntoskrnl/kd/kdio.c     | 9 ++++++---
 ntoskrnl/kd64/kdinit.c | 3 ++-
 3 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/ntoskrnl/ex/init.c b/ntoskrnl/ex/init.c
index 826cc3b3565..1e9a9c07f89 100644
--- a/ntoskrnl/ex/init.c
+++ b/ntoskrnl/ex/init.c
@@ -1580,8 +1580,9 @@ Phase1InitializationDiscard(IN PVOID Context)
                                WINDOWS_NT_INFO_STRING,
                                &MsgEntry);
 
-    /* Get total RAM size */
-    Size = MmNumberOfPhysicalPages * PAGE_SIZE / 1024 / 1024;
+    /* Get total RAM size, in MiB */
+    /* Round size up. Assumed to better match actual physical RAM size */
+    Size = ALIGN_UP_BY(MmNumberOfPhysicalPages * PAGE_SIZE, 1024 * 1024) / (1024 * 1024);
 
     /* Create the string */
     StringBuffer = InitBuffer->VersionBuffer;
diff --git a/ntoskrnl/kd/kdio.c b/ntoskrnl/kd/kdio.c
index 53c99c43d47..38a1d3fc9a2 100644
--- a/ntoskrnl/kd/kdio.c
+++ b/ntoskrnl/kd/kdio.c
@@ -93,7 +93,8 @@ KdpGetMemorySizeInMBs(IN PLOADER_PARAMETER_BLOCK LoaderBlock)
         }
     }
 
-    return NumberOfPhysicalPages * PAGE_SIZE / 1024 / 1024;
+    /* Round size up. Assumed to better match actual physical RAM size */
+    return ALIGN_UP_BY(NumberOfPhysicalPages * PAGE_SIZE, 1024 * 1024) / (1024 * 1024);
 }
 
 /* See also: kd64\kdinit.c */
@@ -255,7 +256,8 @@ KdpInitDebugLog(PKD_DISPATCH_TABLE DispatchTable,
         KeInitializeSpinLock(&KdpDebugLogSpinLock);
 
         /* Display separator + ReactOS version at start of the debug log */
-        MemSizeMBs = MmNumberOfPhysicalPages * PAGE_SIZE / 1024 / 1024;
+        /* Round size up. Assumed to better match actual physical RAM size */
+        MemSizeMBs = ALIGN_UP_BY(MmNumberOfPhysicalPages * PAGE_SIZE, 1024 * 1024) / (1024 * 1024);
         KdpPrintBanner(MemSizeMBs);
     }
     else if (BootPhase == 2)
@@ -554,7 +556,8 @@ KdpScreenInit(PKD_DISPATCH_TABLE DispatchTable,
         KeInitializeSpinLock(&KdpDmesgLogSpinLock);
 
         /* Display separator + ReactOS version at start of the debug log */
-        MemSizeMBs = MmNumberOfPhysicalPages * PAGE_SIZE / 1024 / 1024;
+        /* Round size up. Assumed to better match actual physical RAM size */
+        MemSizeMBs = ALIGN_UP_BY(MmNumberOfPhysicalPages * PAGE_SIZE, 1024 * 1024) / (1024 * 1024);
         KdpPrintBanner(MemSizeMBs);
     }
     else if (BootPhase == 2)
diff --git a/ntoskrnl/kd64/kdinit.c b/ntoskrnl/kd64/kdinit.c
index 64a7c7b5194..b6a8beb9ce9 100644
--- a/ntoskrnl/kd64/kdinit.c
+++ b/ntoskrnl/kd64/kdinit.c
@@ -62,7 +62,8 @@ KdpGetMemorySizeInMBs(IN PLOADER_PARAMETER_BLOCK LoaderBlock)
         }
     }
 
-    return NumberOfPhysicalPages * PAGE_SIZE / 1024 / 1024;
+    /* Round size up. Assumed to better match actual physical RAM size */
+    return ALIGN_UP_BY(NumberOfPhysicalPages * PAGE_SIZE, 1024 * 1024) / (1024 * 1024);
 }
 
 /* See also: kd\kdio.c */