Branch: refs/heads/master Home: https://github.com/tianocore/edk2 Commit: 9280f16345755708ebd9553b3caee077ade0e592 https://github.com/tianocore/edk2/commit/9280f16345755708ebd9553b3caee077ade0e592 Author: Oliver Smith-Denny <o...@microsoft.com> Date: 2025-07-08 (Tue, 08 Jul 2025)
Changed paths: M UefiPayloadPkg/UefiPayloadEntry/Ia32/DxeLoadFunc.c M UefiPayloadPkg/UefiPayloadEntry/Ia32/DxeLoadFuncFit.c M UefiPayloadPkg/UefiPayloadEntry/X64/DxeLoadFunc.c M UefiPayloadPkg/UefiPayloadEntry/X64/DxeLoadFuncFit.c M UefiPayloadPkg/UefiPayloadEntry/X64/VirtualMemory.c Log Message: ----------- UefiPayloadPkg: Don't Allocate Page 0 UefiPayloadPkg has copied the MdeModulePkg DxeIpl behavior to create a memory allocation HOB for page 0. That is being changed (see that commit for details), so also remove it here. Signed-off-by: Oliver Smith-Denny <o...@microsoft.com> Commit: 83b30736bfb57b3895a089968319fb5c0cd42a28 https://github.com/tianocore/edk2/commit/83b30736bfb57b3895a089968319fb5c0cd42a28 Author: Oliver Smith-Denny <o...@microsoft.com> Date: 2025-07-08 (Tue, 08 Jul 2025) Changed paths: M OvmfPkg/Library/PeilessStartupLib/DxeLoad.c M OvmfPkg/Library/PeilessStartupLib/X64/VirtualMemory.c Log Message: ----------- OvmfPkg: Don't Allocate Page 0 OvmfPkg has copied the MdeModulePkg DxeIpl behavior to create a memory allocation HOB for page 0. That is being changed (see that commit for details), so also remove it here. Signed-off-by: Oliver Smith-Denny <o...@microsoft.com> Commit: 91bb5cee36fe52ef012ddbead4f5932b3f9fd862 https://github.com/tianocore/edk2/commit/91bb5cee36fe52ef012ddbead4f5932b3f9fd862 Author: Oliver Smith-Denny <o...@microsoft.com> Date: 2025-07-08 (Tue, 08 Jul 2025) Changed paths: M MdeModulePkg/Core/Dxe/Mem/Page.c M MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c M MdeModulePkg/Core/DxeIplPeim/X64/DxeLoadFunc.c M MdeModulePkg/Core/DxeIplPeim/X64/VirtualMemory.c M MdeModulePkg/Core/DxeIplPeim/X64/VirtualMemory.h M MdeModulePkg/Core/Pei/Memory/MemoryServices.c Log Message: ----------- MdeModulePkg: Don't Allocate Page 0 Currently DxeIpl attempts to set page 0 to all 0's and to create a memory allocation HOB for it. However, DxeIpl will also unmap the page when mapping page tables and if null detection is not enabled, DxeCore will set the page to 0, regardless of allocation status. Because no consumers are using the memory allocation HOB for page 0, drop it. Instead, ensure that PeiCore and DxeCore do not allow allocating page 0; it should always be reserved for null pointer detection. It also complicates the story for platforms that are attempting to audit the system and ensure that no modules are using page 0. With these memory allocation HOBs in place, it is difficult to tell if it is simply DxeIpl who has allocated the memory or another module. This commit drops the memory allocation HOB publishing and ensures that DxeCore and PeiCore do not allocate page 0. DxeCore already will not allocate page 0 to callers of AllocatePages who call with a type other than AllocateAddress, this just changes so that AllocateAddress cannot allocate at page 0 (which if null detection is enabled will cause a page fault). PeiCore does not have AllocateAddress and so this ensures standard allocations do not receive page 0. Signed-off-by: Oliver Smith-Denny <o...@microsoft.com> Compare: https://github.com/tianocore/edk2/compare/0277d5d8f100...91bb5cee36fe To unsubscribe from these emails, change your notification settings at https://github.com/tianocore/edk2/settings/notifications _______________________________________________ edk2-commits mailing list edk2-commits@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/edk2-commits