Within function ApWakeupFunction(): When source level debugger is enabled, AP interrupts will be enabled by EnableDebugAgent(). Then the AP function will be execeuted by:
Procedure (Parameter); After the AP function returns, AP interrupts will be disabled when the APs are placed in loop mode (both HltLoop and MwaiLoop). However, at ExitBootServices, ApWakeupFunction() is called with 'Procedure' equals to RelocateApLoop(). (ExitBootServices callback registered within InitMpGlobalData()) RelocateApLoop() never retuns, so it has to disable the AP interrupts by itself. However, we find that interrupts are only disabled for the HltLoop case, but not for the MwaitLoop case (within file MpFuncs.nasm). This commit adds the missing disabling of AP interrupts for MwaitLoop. Also, for X64, this commit will disable the interrupts before switching to 32-bit mode. Cc: Laszlo Ersek <[email protected]> Cc: Jeff Fan <[email protected]> Cc: Ruiyu Ni <[email protected]> Cc: Jiewen Yao <[email protected]> Cc: Jian J Wang <[email protected]> Cc: Star Zeng <[email protected]> Cc: Eric Dong <[email protected]> Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Hao Wu <[email protected]> --- UefiCpuPkg/Library/MpInitLib/Ia32/MpFuncs.nasm | 3 ++- UefiCpuPkg/Library/MpInitLib/X64/MpFuncs.nasm | 4 +++- 2 files changed, 5 insertions(+), 2 deletions(-) diff --git a/UefiCpuPkg/Library/MpInitLib/Ia32/MpFuncs.nasm b/UefiCpuPkg/Library/MpInitLib/Ia32/MpFuncs.nasm index bd79be0f5e..59e88d3f8f 100644 --- a/UefiCpuPkg/Library/MpInitLib/Ia32/MpFuncs.nasm +++ b/UefiCpuPkg/Library/MpInitLib/Ia32/MpFuncs.nasm @@ -1,5 +1,5 @@ ;------------------------------------------------------------------------------ ; -; Copyright (c) 2015 - 2016, Intel Corporation. All rights reserved.<BR> +; Copyright (c) 2015 - 2018, 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 @@ -239,6 +239,7 @@ AsmRelocateApLoopStart: cmp cl, 1 ; Check mwait-monitor support jnz HltLoop MwaitLoop: + cli mov eax, esp xor ecx, ecx xor edx, edx diff --git a/UefiCpuPkg/Library/MpInitLib/X64/MpFuncs.nasm b/UefiCpuPkg/Library/MpInitLib/X64/MpFuncs.nasm index 7595988884..76f8c078ab 100644 --- a/UefiCpuPkg/Library/MpInitLib/X64/MpFuncs.nasm +++ b/UefiCpuPkg/Library/MpInitLib/X64/MpFuncs.nasm @@ -1,5 +1,5 @@ ;------------------------------------------------------------------------------ ; -; Copyright (c) 2015 - 2017, Intel Corporation. All rights reserved.<BR> +; Copyright (c) 2015 - 2018, 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 @@ -253,6 +253,7 @@ RendezvousFunnelProcEnd: global ASM_PFX(AsmRelocateApLoop) ASM_PFX(AsmRelocateApLoop): AsmRelocateApLoopStart: + cli ; Disable interrupt before switching to 32-bit mode mov rax, [rsp + 40] ; CountTofinish lock dec dword [rax] ; (*CountTofinish)-- mov rsp, r9 @@ -288,6 +289,7 @@ PmEntry: jnz HltLoop mov ebx, edx ; Save C-State to ebx MwaitLoop: + cli mov eax, esp ; Set Monitor Address xor ecx, ecx ; ecx = 0 xor edx, edx ; edx = 0 -- 2.12.0.windows.1 _______________________________________________ edk2-devel mailing list [email protected] https://lists.01.org/mailman/listinfo/edk2-devel
