On 11/10/2016 07:26 PM, Kani, Toshimitsu wrote: > On Thu, 2016-11-10 at 14:14 +0100, Borislav Petkov wrote: >> + Toshi. >> >> On Wed, Nov 09, 2016 at 06:34:48PM -0600, Tom Lendacky wrote: >>> >>> For processors that support PAT, set the write-protect cache mode >>> (_PAGE_CACHE_MODE_WP) entry to the actual write-protect value >>> (x05). > > Using slot 6 may be more cautious (for the same reason slot 7 was used > for WT), but I do not have a strong opinion for it. > > set_page_memtype() cannot track the use of WP type since there is no > extra-bit available for WP, but WP is only supported by > early_memremap_xx() interfaces in this series. So, I think we should > just document that WP is only intended for temporary mappings at boot- > time until this issue is resolved. Also, we need to make sure that > this early_memremap for WP is only called after pat_init() is done. Sounds good, I'll add documentation to cover these points. > > A nit - please add WP to the function header comment below. > "This function initializes PAT MSR and PAT table with an OS-defined > value to enable additional cache attributes, WC and WT." Will do. Thanks, Tom > > Thanks, > -Toshi > -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
