summaryrefslogtreecommitdiff
path: root/arch/x86/include
diff options
context:
space:
mode:
authorHugh Dickins <hughd@google.com>2018-01-29 18:17:58 -0800
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2018-02-13 12:35:55 +0100
commit400d3c8b0c7f6c942cd9bf201da1f32da9bdcc9f (patch)
tree48b5cec979a971324254466d3aac42f70ac23c18 /arch/x86/include
parentae1fc8de51b10dba40cbd54959b5ba0a311c0861 (diff)
kaiser: allocate pgd with order 0 when pti=off
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") Reviewed-by: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/x86/include')
-rw-r--r--arch/x86/include/asm/pgalloc.h11
-rw-r--r--arch/x86/include/asm/pgtable.h6
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);