Hi Jonathan,
On Thu, Jul 30, 2015 at 10:35:04PM +0100, Jonathan (Zhixiong) Zhang wrote:
From: "Jonathan (Zhixiong) Zhang" zjzhang@codeaurora.org
On a platform with APEI (ACPI Platform Error Interface) enabled, firmware updates a memory region with hardware error record using nocache attribute. When OS reads the region, since it maps the region with cacahed attribute even though EFI memory map defines this region as uncached, OS gets stale data and errorneously reports there is no new HW error.
When ghes driver maps the memory region, it uses the cache attribute according to EFI memory map, if EFI memory map feature is enabled at runtime.
Since both arch/x86 and arch/ia64 implemented architecture agnostic EFI memory map attribue lookup function efi_memattributes(), the code is moved from arch/x86 into EFI subsystem and is declared as __weak; archs other than ia64 should not override the default implementation.
V9:
- Rebased to arm64-upstream-14543 of arm64/master.
- Match strict MM type in arch_apei_get_mem_attribute().
I guess this is all going via Matt's tree? I'm happy to take the new memory type in arch/arm64/ if there's nothing currently queued, but I suspect it makes more sense for it to stay together.
Will