Undo pageattr_64 parts of 4157e20af49a04d75a807e6d15b3e70c8e688ccc Note sure what the point of that change was Author: Venkatesh Pallipadi Date: Tue Jan 15 16:53:24 2008 +0100 patches/x86-pat-usable_only_map.patch x86_64: Map only usable memory in identity map. Reserved memory maps to a zero page. Signed-off-by: Venkatesh Pallipadi Signed-off-by: Suresh Siddha Signed-off-by: Andi Kleen --- arch/x86/mm/pageattr_64.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) Index: linux/arch/x86/mm/pageattr_64.c =================================================================== --- linux.orig/arch/x86/mm/pageattr_64.c +++ linux/arch/x86/mm/pageattr_64.c @@ -53,11 +53,9 @@ split_large_page(unsigned long address, /* * page_private is used to track the number of entries in * the page table page have non standard attributes. - * Count of 1 indicates page split by split_large_page(), - * additional count indicates the number of pages with non-std attr. */ SetPagePrivate(base); - page_private(base) = 1; + page_private(base) = 0; address = __pa(address); addr = address & LARGE_PAGE_MASK; @@ -178,8 +176,11 @@ __change_page_attr(unsigned long address BUG(); } + /* on x86-64 the direct mapping set at boot is not using 4k pages */ + BUG_ON(PageReserved(kpte_page)); + save_page(kpte_page); - if (page_private(kpte_page) == 1) + if (page_private(kpte_page) == 0) revert_page(address, ref_prot); return 0; }