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* UefiCpuPkg: Fix nasm warning "signed byte value exceeds"Zhiguang Liu2022-07-251-4/+3
| | | | | | | | | | | | | | | | | | | | | Currently, "push byte %[Vector]" causes nasm warning when Vector is larger than 0x7F. This is because push accepts a signed value, and byte means signed int8. Maximum signed int8 is 0x7F. When Vector is larger the 0x7F, for example, when Vector is 255, byte 255 turns to -1, and causes the warning "signed byte value exceeds". To avoid such warning, use dword instead of byte, this will increase 3 bytes for each IdtVector. For IA32, the size of IdtVector will increase from 10 bytes to 13 bytes. For X64, the size of IdtVector will increase from 15 bytes to 18 bytes. Cc: Eric Dong <eric.dong@intel.com> Cc: Ray Ni <ray.ni@intel.com> Cc: Rahul Kumar <rahul1.kumar@intel.com> Cc: Debkumar De <debkumar.de@intel.com> Cc: Harry Han <harry.han@intel.com> Cc: Catharine West <catharine.west@intel.com> Reviewed-by: Ray Ni <ray.ni@intel.com> Signed-off-by: Zhiguang Liu <zhiguang.liu@intel.com>
* CpuException: Avoid allocating code pages for DXE instanceRay Ni2022-06-101-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | Today the DXE instance allocates code page and then copies the IDT vectors to the allocated code page. Then it fixes up the vector number in the IDT vector. But if we update the NASM file to generate 256 IDT vectors, there is no need to do the copy and fix-up. A side effect is 4096 bytes (HOOKAFTER_STUB_SIZE * 256) is used for 256 IDT vectors while 32 IDT vectors only require 512 bytes without this change, in following library instances: 1. 32bit SecPeiCpuExceptionHandlerLib and PeiCpuExceptionHandlerLib 2. 64bit PeiCpuExceptionHandlerLib But considering the code logic simplification, 3.5K extra space is not a big deal. If 3.5K is too much, we can enhance the code further to generate 32 vectors for above mentioned library instances. Signed-off-by: Ray Ni <ray.ni@intel.com> Reviewed-by: Jian J Wang <jian.j.wang@intel.com> Acked-by: Eric Dong <eric.dong@intel.com>
* UefiCpuPkg: Replace Opcode with the corresponding instructions.Jason2022-03-011-5/+6
| | | | | | | | | | | | | | | | REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3790 Replace Opcode with the corresponding instructions. The code changes have been verified with CompareBuild.py tool, which can be used to compare the results of two different EDK II builds to determine if they generate the same binaries. (tool link: https://github.com/mdkinney/edk2/tree/sandbox/CompareBuild) Signed-off-by: Jason Lou <yun.lou@intel.com> Reviewed-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: Replace BSD License with BSD+Patent LicenseMichael D Kinney2019-04-091-7/+1
| | | | | | | | | | | | | | | | | | | | | https://bugzilla.tianocore.org/show_bug.cgi?id=1373 Replace BSD 2-Clause License with BSD+Patent License. This change is based on the following emails: https://lists.01.org/pipermail/edk2-devel/2019-February/036260.html https://lists.01.org/pipermail/edk2-devel/2018-October/030385.html RFCs with detailed process for the license change: V3: https://lists.01.org/pipermail/edk2-devel/2019-March/038116.html V2: https://lists.01.org/pipermail/edk2-devel/2019-March/037669.html V1: https://lists.01.org/pipermail/edk2-devel/2019-March/037500.html Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Michael D Kinney <michael.d.kinney@intel.com> Reviewed-by: Eric Dong <eric.dong@intel.com> Reviewed-by: Ray Ni <ray.ni@intel.com>
* UefiCpuPkg: restore strict page attributes via #DB in nonstop mode onlyJian J Wang2019-03-011-7/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1576 The root cause of this issue is that non-stop mode of Heap Guard and NULL Detection set TF bit (single-step) in EFLAG unconditionally in the common handler in CpuExceptionLib. If PcdCpuSmmStaticPageTable is FALSE, the SMM will only create page table for memory below 4G. If SMM tries to access memory beyond 4G, a page fault exception will be triggered and the memory to access will be added to page table so that SMM code can continue the access. Because of above issue, the TF bit is set after the page fault is handled and then fall into another DEBUG exception. Since non-stop mode of Heap Guard and NULL Detection are not enabled, no special DEBUG exception handler is registered. The default handler just prints exception context and go into dead loop. Actually EFLAGS can be changed in any standard exception handler. There's no need to do single-step setup in assembly code. So the fix is to move the logic to C code part of page fault exception handler so that we can fully validate the configuration and prevent TF bit from being set unexpectedly. Fixes: dcc026217fdc363f55c217039fc43d344f69fed6 16b918bbaf51211a32ae04d9d8a5ba6ccca25a6a Test: - Pass special test of accessing memory beyond 4G in SMM mode - Boot to OS with Qemu emulator platform (Fedora27, Ubuntu18.04, Windows7, Windows10) Cc: Eric Dong <eric.dong@intel.com> Cc: Laszlo Ersek <lersek@redhat.com> Cc: Ruiyu Ni <ruiyu.ni@intel.com> Cc: Star Zeng <star.zeng@intel.com> Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Jian J Wang <jian.j.wang@intel.com> Acked-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Dong <eric.dong@intel.com>
* UefiCpuPkg/CpuExceptionHandlerLib: Setup single step in #PF handlerJian J Wang2018-08-301-0/+7
| | | | | | | | | | | | | | | | | | | Once the #PF handler has set the page to be 'present', there should be a way to reset it to 'not-present'. 'TF' bit in EFLAGS can be used for this purpose. 'TF' bit will be set in interrupted function context so that it can be triggered once the cpu control returns back to the instruction causing #PF and re-execute it. This is an necessary step to implement non-stop mode for Heap Guard and NULL Pointer Detection feature. Cc: Eric Dong <eric.dong@intel.com> Cc: Laszlo Ersek <lersek@redhat.com> Cc: Ruiyu Ni <ruiyu.ni@intel.com> Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Jian J Wang <jian.j.wang@intel.com> Reviewed-by: Eric Dong <eric.dong@intel.com> Acked-by: Laszlo Ersek <lersek@redhat.com>
* UefiCpuPkg CpuExceptionHandlerLib:Convert Ia32/ExceptionHandlerAsm.asm to NASMLiming Gao2016-06-281-0/+462
The BaseTools/Scripts/ConvertMasmToNasm.py script was used to convert Ia32/ExceptionHandlerAsm.asm to Ia32/ExceptionHandlerAsm.nasm. Then, manually update nasm to pass build. Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Liming Gao <liming.gao@intel.com>