Re: [PATCH] UefiCpuPkg/CpuMp: Fix hang when StackGuard is enabled in 16-core cpu

["Dong, Eric" <eric.dong@intel.com>]

Reviewed-by: Eric Dong <eric.dong@intel.com>

-----Original Message-----
From: Ni, Ray <ray.ni@intel.com> 
Sent: Thursday, January 14, 2021 9:12 PM
To: devel@edk2.groups.io
Cc: Dong, Eric <eric.dong@intel.com>; Laszlo Ersek <lersek@redhat.com>; Kumar, Rahul1 <rahul1.kumar@intel.com>
Subject: [PATCH] UefiCpuPkg/CpuMp: Fix hang when StackGuard is enabled in 16-core cpu

When StackGuard is enabled, the CpuMp driver allocates
known good stacks for all CPUs for DF# and PF# exceptions.
It uses AllocatePool to do so.

The size needed equals to 64KB
= StackSize (2K) * ExceptionNumber (2) * NumberOfProcessors (16)

However, AllocatePool max allocation size is less than 64K.
To fix the issue, AllocatePages() is used.

Signed-off-by: Ray Ni <ray.ni@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
---
 UefiCpuPkg/CpuMpPei/CpuMpPei.c   | 10 +++-------
 UefiCpuPkg/CpuMpPei/CpuMpPei.h   |  3 ++-
 UefiCpuPkg/CpuMpPei/CpuMpPei.inf |  3 ++-
 3 files changed, 7 insertions(+), 9 deletions(-)

diff --git a/UefiCpuPkg/CpuMpPei/CpuMpPei.c b/UefiCpuPkg/CpuMpPei/CpuMpPei.c
index d07540cf74..40729a09b9 100644
--- a/UefiCpuPkg/CpuMpPei/CpuMpPei.c
+++ b/UefiCpuPkg/CpuMpPei/CpuMpPei.c
@@ -1,7 +1,7 @@
 /** @file

   CPU PEI Module installs CPU Multiple Processor PPI.

 

-  Copyright (c) 2015 - 2019, Intel Corporation. All rights reserved.<BR>

+  Copyright (c) 2015 - 2021, Intel Corporation. All rights reserved.<BR>

   SPDX-License-Identifier: BSD-2-Clause-Patent

 

 **/

@@ -532,13 +532,9 @@ InitializeMpExceptionStackSwitchHandlers (
   ExceptionNumber = FixedPcdGetSize (PcdCpuStackSwitchExceptionList);

   NewStackSize = FixedPcdGet32 (PcdCpuKnownGoodStackSize) * ExceptionNumber;

 

-  Status = PeiServicesAllocatePool (

-             NewStackSize * NumberOfProcessors,

-             (VOID **)&StackTop

-             );

+  StackTop = AllocatePages (EFI_SIZE_TO_PAGES (NewStackSize * NumberOfProcessors));

   ASSERT(StackTop != NULL);

-  if (EFI_ERROR (Status)) {

-    ASSERT_EFI_ERROR (Status);

+  if (StackTop == NULL) {

     return;

   }

   StackTop += NewStackSize  * NumberOfProcessors;

diff --git a/UefiCpuPkg/CpuMpPei/CpuMpPei.h b/UefiCpuPkg/CpuMpPei/CpuMpPei.h
index 6a481a84dc..c6870656ca 100644
--- a/UefiCpuPkg/CpuMpPei/CpuMpPei.h
+++ b/UefiCpuPkg/CpuMpPei/CpuMpPei.h
@@ -1,7 +1,7 @@
 /** @file

   Definitions to install Multiple Processor PPI.

 

-  Copyright (c) 2015 - 2019, Intel Corporation. All rights reserved.<BR>

+  Copyright (c) 2015 - 2021, Intel Corporation. All rights reserved.<BR>

   SPDX-License-Identifier: BSD-2-Clause-Patent

 

 **/

@@ -27,6 +27,7 @@
 #include <Library/CpuExceptionHandlerLib.h>

 #include <Library/MpInitLib.h>

 #include <Library/BaseMemoryLib.h>

+#include <Library/MemoryAllocationLib.h>

 

 extern EFI_PEI_PPI_DESCRIPTOR   mPeiCpuMpPpiDesc;

 

diff --git a/UefiCpuPkg/CpuMpPei/CpuMpPei.inf b/UefiCpuPkg/CpuMpPei/CpuMpPei.inf
index 7e511325d8..ba829d816e 100644
--- a/UefiCpuPkg/CpuMpPei/CpuMpPei.inf
+++ b/UefiCpuPkg/CpuMpPei/CpuMpPei.inf
@@ -1,7 +1,7 @@
 ## @file

 #  CPU driver installs CPU PI Multi-processor PPI.

 #

-#  Copyright (c) 2015 - 2019, Intel Corporation. All rights reserved.<BR>

+#  Copyright (c) 2015 - 2021, Intel Corporation. All rights reserved.<BR>

 #  SPDX-License-Identifier: BSD-2-Clause-Patent

 #

 ##

@@ -45,6 +45,7 @@ [LibraryClasses]
   MpInitLib

   BaseMemoryLib

   CpuLib

+  MemoryAllocationLib

 

 [Guids]

   gEdkiiMigratedFvInfoGuid                                             ## SOMETIMES_CONSUMES     ## HOB

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2.27.0.windows.1