sravan/system76-edk2
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

UefiCpuPkg/PiSmmCpuDxeSmm: Decrease mNumberToFinish in AP safe code

Browse Source 
We will put APs into hlt-loop in safe code. But we decrease mNumberToFinish
before APs enter into the safe code. Paolo pointed out this gap.

This patch is to move mNumberToFinish decreasing to the safe code. It could
make sure BSP could wait for all APs are running in safe code.

https://bugzilla.tianocore.org/show_bug.cgi?id=216

Reported-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jeff Fan <jeff.fan@intel.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>
This commit is contained in:
Jeff Fan
2016-11-11 13:25:51 +08:00
parent 45e3440ac2
commit ec8a387700
4 changed files with 18 additions and 15 deletions
Download Patch File Download Diff File Expand all files Collapse all files

17
UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c
View File

@@ -79,9 +79,11 @@ BOOLEAN mAcpiS3Enable = TRUE;
UINT8 *mApHltLoopCode = NULL;
UINT8 mApHltLoopCodeTemplate[] = {
0xFA, // cli
0xF4, // hlt
0xEB, 0xFC // jmp $-2
0x8B, 0x44, 0x24, 0x04, // mov eax, dword ptr [esp+4]
0xF0, 0xFF, 0x08, // lock dec dword ptr [eax]
0xFA, // cli
0xF4, // hlt
0xEB, 0xFC // jmp $-2
};
/**
@@ -399,17 +401,12 @@ MPRendezvousProcedure (
}
//
// Count down the number with lock mechanism.
//
InterlockedDecrement (&mNumberToFinish);
//
// Place AP into the safe code
// Place AP into the safe code, count down the number with lock mechanism in the safe code.
//
TopOfStack = (UINT32) (UINTN) Stack + sizeof (Stack);
TopOfStack &= ~(UINT32) (CPU_STACK_ALIGNMENT - 1);
CopyMem ((VOID *) (UINTN) mApHltLoopCode, mApHltLoopCodeTemplate, sizeof (mApHltLoopCodeTemplate));
TransferApToSafeState ((UINT32) (UINTN) mApHltLoopCode, TopOfStack);
TransferApToSafeState ((UINT32) (UINTN) mApHltLoopCode, TopOfStack, &mNumberToFinish);
}
/**