From 9a34087280a857eb0b80ff27d0efabc540b36f99 Mon Sep 17 00:00:00 2001 From: mdkinney Date: Fri, 22 Mar 2013 21:18:02 +0000 Subject: [PATCH] Fix a bug in the DXE Core that generates an ASSERT() when the page at address zero is freed and DEBUG_CLEAR_MEMORY() macros are enabled. If DEBUG_CLEAR_MEMORY() is enabled and the page at address 0 is freed, then DEBUG_CLEAR_MEMORY() is invoked skipping over the first 4K page. Signed-off-by: Michael Kinney Reviewed-by: Laszlo Ersek Reviewed-by: Jordan Justen git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@14217 6f19259b-4bc3-4df7-8a09-765794883524 --- MdeModulePkg/Core/Dxe/Mem/Page.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/MdeModulePkg/Core/Dxe/Mem/Page.c b/MdeModulePkg/Core/Dxe/Mem/Page.c index 6d5a259eb6..8a6d35d6e4 100644 --- a/MdeModulePkg/Core/Dxe/Mem/Page.c +++ b/MdeModulePkg/Core/Dxe/Mem/Page.c @@ -1,7 +1,7 @@ /** @file UEFI Memory page management functions. -Copyright (c) 2007 - 2012, Intel Corporation. All rights reserved.
+Copyright (c) 2007 - 2013, Intel Corporation. All rights reserved.
This program and the accompanying materials are licensed and made available under the terms and conditions of the BSD License which accompanies this distribution. The full text of the license may be found at @@ -834,7 +834,18 @@ CoreConvertPages ( // CoreAddRange (NewType, Start, RangeEnd, Attribute); if (NewType == EfiConventionalMemory) { - DEBUG_CLEAR_MEMORY ((VOID *)(UINTN) Start, (UINTN) (RangeEnd - Start + 1)); + // + // Avoid calling DEBUG_CLEAR_MEMORY() for an address of 0 because this + // macro will ASSERT() if address is 0. Instead, CoreAddRange() guarantees + // that the page starting at address 0 is always filled with zeros. + // + if (Start == 0) { + if (RangeEnd > EFI_PAGE_SIZE) { + DEBUG_CLEAR_MEMORY ((VOID *)(UINTN) EFI_PAGE_SIZE, (UINTN) (RangeEnd - EFI_PAGE_SIZE + 1)); + } + } else { + DEBUG_CLEAR_MEMORY ((VOID *)(UINTN) Start, (UINTN) (RangeEnd - Start + 1)); + } } // -- 2.39.2