Reviewed-by: Pavel Tatashin pasha.tatashin@oracle.com
On 01/29/2018 09:17 PM, Hugh Dickins wrote:
The 4.9.77 version of "x86/pti/efi: broken conversion from efi to kernel page table" looked nicer than the 4.4.112 version, but was suboptimal on machines booted with "pti=off" (or on AMD machines): it allocated pgd with an order 1 page whatever the setting of kaiser_enabled.
Fix that by moving the definition of PGD_ALLOCATION_ORDER from asm/pgalloc.h to asm/pgtable.h, which already defines kaiser_enabled.
Fixes: 1b92c48a2eeb ("x86/pti/efi: broken conversion from efi to kernel page table") Cc: Pavel Tatashin pasha.tatashin@oracle.com Cc: Steven Sistare steven.sistare@oracle.com Cc: Jiri Kosina jkosina@suse.cz Cc: stable@vger.kernel.org Signed-off-by: Hugh Dickins hughd@google.com
arch/x86/include/asm/pgalloc.h | 11 ----------- arch/x86/include/asm/pgtable.h | 6 ++++++ 2 files changed, 6 insertions(+), 11 deletions(-)
diff --git a/arch/x86/include/asm/pgalloc.h b/arch/x86/include/asm/pgalloc.h index 1178a51b77f3..b6d425999f99 100644 --- a/arch/x86/include/asm/pgalloc.h +++ b/arch/x86/include/asm/pgalloc.h @@ -27,17 +27,6 @@ static inline void paravirt_release_pud(unsigned long pfn) {} */ extern gfp_t __userpte_alloc_gfp; -#ifdef CONFIG_PAGE_TABLE_ISOLATION -/*
- Instead of one PGD, we acquire two PGDs. Being order-1, it is
- both 8k in size and 8k-aligned. That lets us just flip bit 12
- in a pointer to swap between the two 4k halves.
- */
-#define PGD_ALLOCATION_ORDER 1 -#else -#define PGD_ALLOCATION_ORDER 0 -#endif
- /*
*/
- Allocate and free page tables.
diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h index 2536f90cd30c..5af0401ccff2 100644 --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -20,9 +20,15 @@ #ifdef CONFIG_PAGE_TABLE_ISOLATION extern int kaiser_enabled; +/*
- Instead of one PGD, we acquire two PGDs. Being order-1, it is
- both 8k in size and 8k-aligned. That lets us just flip bit 12
- in a pointer to swap between the two 4k halves.
- */ #else #define kaiser_enabled 0 #endif
+#define PGD_ALLOCATION_ORDER kaiser_enabled void ptdump_walk_pgd_level(struct seq_file *m, pgd_t *pgd); void ptdump_walk_pgd_level_checkwx(void);