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MdePkg-SmmMemLib: Enhance SmmIsBufferOutsideSmmValid() check for fixed comm buffer.

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This patch adds more check in SmmIsBufferOutsideSmmValid(), to make sure that
SMM communication buffer is only EfiReservedMemoryType/EfiRuntimeServicesCode/
EfiRuntimeServicesData/EfiACPIMemoryNVS. So that the communication buffer will
not touch any OS memory.

The assumption is that a platform reports valid SMM communication buffer at
EndOfDxe, because EndOfDxe is last hook point that SMM code can call-out to
get memory map information.
A platform MUST finish SMM communication buffer allocation before EndOfDxe.
If a DXE or OS driver need do communication after EndOfDxe, it can either
allocate SMM communication buffer before EndOfDxe and save it, or consume
EDKII_PI_SMM_COMMUNICATION_REGION_TABLE table to get general fixed comm buffer.

This is designed to meet Microsoft WSMT table definition on FIXED_COMM_BUFFERS
requirement.

Cc: Liming Gao <liming.gao@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jiewen Yao <jiewen.yao@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
This commit is contained in:
Jiewen Yao
2016-04-22 15:49:28 +08:00
parent 009264f5cf
commit 91f51fcc84
2 changed files with 183 additions and 3 deletions
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6
MdePkg/Library/SmmMemLib/SmmMemLib.inf
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@@ -6,7 +6,7 @@
# all SMRAM range via SMM_ACCESS2_PROTOCOL, including the range for firmware (like SMM Core
# and SMM driver) and/or specific dedicated hardware.
#
# Copyright (c) 2015, Intel Corporation. All rights reserved.<BR>
# Copyright (c) 2015 - 2016, Intel Corporation. All rights reserved.<BR>
# 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
@@ -49,7 +49,9 @@
MemoryAllocationLib
[Protocols]
gEfiSmmAccess2ProtocolGuid ## CONSUMES
gEfiSmmAccess2ProtocolGuid ## CONSUMES
gEfiSmmReadyToLockProtocolGuid ## CONSUMES
gEfiSmmEndOfDxeProtocolGuid ## CONSUMES
[Depex]
gEfiSmmAccess2ProtocolGuid