Hi Mike, In my experience, AllocatePages only can allocate the memory with EFI_RESOURCE_SYSTEM_MEMORY type. Don't you get any alert when using AllocatePages to allocate the memory with EFI_RESOURCE_MEMORY_RESERVED type?
Thanks, Simon Chu -----Original Message----- From: Mike Maslenkin [mailto:miha...@parallels.com] Sent: Tuesday, March 04, 2014 4:59 AM To: edk2-devel@lists.sourceforge.net Subject: [edk2] Reserved memory regions. Hello! Could someone correct my understanding of reserved memory regions? I want to reserve some region (below 4G) but this region must be accessible for OS. To be clear this is ACPI NVS region which must be accessible for Linux Kernel, i.e request_mem_region() must succeed. So what I am doing: On PEI phase I create two HOBs: BuildResourceDescriptorHob ( EFI_RESOURCE_SYSTEM_MEMORY, EFI_RESOURCE_ATTRIBUTE_PRESENT | EFI_RESOURCE_ATTRIBUTE_INITIALIZED | EFI_RESOURCE_ATTRIBUTE_UNCACHEABLE | EFI_RESOURCE_ATTRIBUTE_WRITE_COMBINEABLE | EFI_RESOURCE_ATTRIBUTE_WRITE_THROUGH_CACHEABLE | EFI_RESOURCE_ATTRIBUTE_WRITE_BACK_CACHEABLE | EFI_RESOURCE_ATTRIBUTE_TESTED, BASE_1MB, LowerMemorySize - ReservedMemorySize) ); BuildResourceDescriptorHob ( EFI_RESOURCE_MEMORY_RESERVED, EFI_RESOURCE_ATTRIBUTE_PRESENT | EFI_RESOURCE_ATTRIBUTE_INITIALIZED | EFI_RESOURCE_ATTRIBUTE_UNCACHEABLE | EFI_RESOURCE_ATTRIBUTE_TESTED, ReservedMemoryBase, ReservedMemorySize ); So, DXE phase will not use reserved memory. To insert this reserved memory region to EFI memory map I call gBS->AllocatePages ( AllocateAddress, EfiACPIMemoryNVS, EFI_SIZE_TO_PAGES (ReservedMemorySize), ReservedMemoryBase ); So, everyone is happy, OS kernels (Linux, Windows) successfully maps this memory. But CSM LegacyBiosDxe asserts. LegacyBiosBuildE820 function detects overlapped memory region, because it processes EFI memory map and HOB list during E820 map building. AllocatePages() adds this region to memory map, while HOB list still contains it also. So here is a question: Am I reserve memory region correctly or there is a some inaccuracy at LegacyBiosDxe? ------------------------------------------------------------------------------ Subversion Kills Productivity. Get off Subversion & Make the Move to Perforce. With Perforce, you get hassle-free workflows. Merge that actually works. Faster operations. Version large binaries. Built-in WAN optimization and the freedom to use Git, Perforce or both. Make the move to Perforce. http://pubads.g.doubleclick.net/gampad/clk?id=122218951&iu=/4140/ostg.clktrk _______________________________________________ edk2-devel mailing list edk2-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/edk2-devel ------------------------------------------------------------------------------ Subversion Kills Productivity. Get off Subversion & Make the Move to Perforce. With Perforce, you get hassle-free workflows. Merge that actually works. Faster operations. Version large binaries. Built-in WAN optimization and the freedom to use Git, Perforce or both. Make the move to Perforce. http://pubads.g.doubleclick.net/gampad/clk?id=122218951&iu=/4140/ostg.clktrk _______________________________________________ edk2-devel mailing list edk2-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/edk2-devel
