b721aa749b
Commit2ac1730bf2(MdeModulePkg/DxeIpl: Mark page table as read-only) sets the memory pages used for page table as read-only after paging is setup and sets CR0.WP to protect CPU modifying the read-only pages. The commit causes #PF when MemEncryptSevClearPageEncMask() or MemEncryptSevSetPageEncMask() tries to change the page-table attributes. This patch takes the similar approach as Commit147fd35c3e(UefiCpuPkg/CpuDxe: Enable protection for newly added page table). When page table protection is enabled, we disable it temporarily before changing the page table attributes. This patch makes use of the same approach as Commit2ac1730bf2(MdeModulePkg/DxeIpl: Mark page table as read-only)) for allocating page table memory from reserved memory pool, which helps to reduce a potential "split" operation. The patch duplicates code from commit147fd35c3e. The code duplication will be removed after we implement page table manipulation library. See bugzilla https://bugzilla.tianocore.org/show_bug.cgi?id=847. Cc: Jian J Wang <jian.j.wang@intel.com> Cc: Jiewen Yao <jiewen.yao@intel.com> Cc: Jordan Justen <jordan.l.justen@intel.com> Cc: Laszlo Ersek <lersek@redhat.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> Acked-by: Laszlo Ersek <lersek@redhat.com>
EDK II Project
A modern, feature-rich, cross-platform firmware development environment for the UEFI and PI specifications from www.uefi.org.
Contributions to the EDK II open source project are covered by the TianoCore Contribution Agreement 1.1
The majority of the content in the EDK II open source project uses a BSD 2-Clause License. The EDK II open source project contains the following components that are covered by additional licenses:
- AppPkg/Applications/Python/Python-2.7.2/Tools/pybench
- AppPkg/Applications/Python/Python-2.7.2
- AppPkg/Applications/Python/Python-2.7.10
- BaseTools/Source/C/BrotliCompress
- MdeModulePkg/Library/BrotliCustomDecompressLib
- OvmfPkg
- CryptoPkg/Library/OpensslLib/openssl
The EDK II Project is composed of packages. The maintainers for each package are listed in Maintainers.txt.