From: Andy Lutomirski This allows the cpu entry area PMDs to be shared between the kernel and user space page tables. [ tglx: Fixed bottom of by one and added guards so other fixmaps can be added later ] Signed-off-by: Andy Lutomirski Signed-off-by: Thomas Gleixner --- arch/x86/include/asm/fixmap.h | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) --- a/arch/x86/include/asm/fixmap.h +++ b/arch/x86/include/asm/fixmap.h @@ -134,16 +134,22 @@ enum fixed_addresses { #ifdef CONFIG_PARAVIRT FIX_PARAVIRT_BOOTMAP, #endif - FIX_TEXT_POKE1, /* reserve 2 pages for text_poke() */ - FIX_TEXT_POKE0, /* first page is last, because allocation is backward */ #ifdef CONFIG_X86_INTEL_MID FIX_LNW_VRTC, #endif - /* Fixmap entries to remap the GDTs, one per processor. */ + FIX_TEXT_POKE1, /* reserve 2 pages for text_poke() */ + FIX_TEXT_POKE0, /* first page is last, because allocation is backward */ + + /* + * Fixmap entries to remap the IDT, and the per cpu entry areas. + * Aligend to a PMD boundary. + */ + FIX_USR_SHARED_TOP = round_up(FIX_TEXT_POKE0 + 1, PTRS_PER_PMD), FIX_CPU_ENTRY_AREA_TOP, FIX_CPU_ENTRY_AREA_BOTTOM = FIX_CPU_ENTRY_AREA_TOP + (CPU_ENTRY_AREA_PAGES * NR_CPUS) - 1, + FIX_USR_SHARED_BOTTOM = round_up(FIX_CPU_ENTRY_AREA_BOTTOM + 2, PTRS_PER_PMD) - 1, - __end_of_permanent_fixed_addresses, + __end_of_permanent_fixed_addresses = FIX_USR_SHARED_BOTTOM, /* * 512 temporary boot-time mappings, used by early_ioremap(),