The EFI runtime code we need to map, but we shouldn't use as RAM. I suspect this is also true for the ACPI areas.
Jacob Shin <jacob.s...@amd.com> wrote: >On Fri, Aug 24, 2012 at 09:54:04PM -0700, Yinghai Lu wrote: >> On Fri, Aug 24, 2012 at 9:24 PM, Jacob Shin <jacob.s...@amd.com> >wrote: >> > On Fri, Aug 24, 2012 at 06:07:01PM -0700, Yinghai Lu wrote: >> >> On Fri, Aug 24, 2012 at 4:55 PM, Jacob Shin <jacob.s...@amd.com> >wrote: >> >> >> >> looks like you could avoid add pfn_mapped[] array. >> >> >> >> pfn_range_is_mapped() should be >> >> check max_low_pfn_mapped, max_pfn_mapped with >> >> e820_all_mapped(start, end, E820_RAM). >> > >> > Hmm .. I guess that could work .. but what about EFI code that keys >off of >> > EFI memory map? Does the EFI code update e820 and mark as E820_RAM >whatever >> > ranges that it calls init_memory_mapping on (via efi_ioremap?) >> >> they are converted to e820 memmap before init_memory_mapping is >called. > >Yinghai, looking into this further on my EFI enabled machine, there is >a >memory range where: > >- e820 marks it as E820_RESERVED >- EFI memory map marks it as EFI_RUNTIME_SERVICES_DATA > >During EFI init, the range is added (redundantly) to e820 as >E820_RESERVED, >but during efi_enter_virtual_mode, direct mappings are created for the >range with a call to efi_ioremap. > >Another such region is EFI_RUNTIME_SERVICES_CODE which is marked as >ACPI NVS. > >So these are not E820_RAM, but direct mapped by EFI code path .. what >do >we do here? I think we should just stick with keeping the pfn_mapped[] >array .. no? > >-Jacob > >> >> Thanks >> >> Yinghai >> -- Sent from my mobile phone. Please excuse brevity and lack of formatting. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
