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-rw-r--r--arch/x86/include/asm/pgtable_64_types.h5
-rw-r--r--arch/x86/mm/dump_pagetables.c15
-rw-r--r--arch/x86/xen/mmu_pv.c11
3 files changed, 17 insertions, 14 deletions
diff --git a/arch/x86/include/asm/pgtable_64_types.h b/arch/x86/include/asm/pgtable_64_types.h
index 7764617b8f9c..bf6d2692fc60 100644
--- a/arch/x86/include/asm/pgtable_64_types.h
+++ b/arch/x86/include/asm/pgtable_64_types.h
@@ -94,6 +94,11 @@ typedef struct { pteval_t pte; } pte_t;
# define __VMEMMAP_BASE _AC(0xffffea0000000000, UL)
#endif
+#define GUARD_HOLE_PGD_ENTRY -256UL
+#define GUARD_HOLE_SIZE (16UL << PGDIR_SHIFT)
+#define GUARD_HOLE_BASE_ADDR (GUARD_HOLE_PGD_ENTRY << PGDIR_SHIFT)
+#define GUARD_HOLE_END_ADDR (GUARD_HOLE_BASE_ADDR + GUARD_HOLE_SIZE)
+
#define LDT_PGD_ENTRY -240UL
#define LDT_BASE_ADDR (LDT_PGD_ENTRY << PGDIR_SHIFT)
diff --git a/arch/x86/mm/dump_pagetables.c b/arch/x86/mm/dump_pagetables.c
index 2a4849e92831..6bca45d06676 100644
--- a/arch/x86/mm/dump_pagetables.c
+++ b/arch/x86/mm/dump_pagetables.c
@@ -51,10 +51,10 @@ struct addr_marker {
enum address_markers_idx {
USER_SPACE_NR = 0,
KERNEL_SPACE_NR,
- LOW_KERNEL_NR,
-#if defined(CONFIG_MODIFY_LDT_SYSCALL) && defined(CONFIG_X86_5LEVEL)
+#ifdef CONFIG_MODIFY_LDT_SYSCALL
LDT_NR,
#endif
+ LOW_KERNEL_NR,
VMALLOC_START_NR,
VMEMMAP_START_NR,
#ifdef CONFIG_KASAN
@@ -62,9 +62,6 @@ enum address_markers_idx {
KASAN_SHADOW_END_NR,
#endif
CPU_ENTRY_AREA_NR,
-#if defined(CONFIG_MODIFY_LDT_SYSCALL) && !defined(CONFIG_X86_5LEVEL)
- LDT_NR,
-#endif
#ifdef CONFIG_X86_ESPFIX64
ESPFIX_START_NR,
#endif
@@ -465,11 +462,11 @@ static inline bool is_hypervisor_range(int idx)
{
#ifdef CONFIG_X86_64
/*
- * ffff800000000000 - ffff87ffffffffff is reserved for
- * the hypervisor.
+ * A hole in the beginning of kernel address space reserved
+ * for a hypervisor.
*/
- return (idx >= pgd_index(__PAGE_OFFSET) - 16) &&
- (idx < pgd_index(__PAGE_OFFSET));
+ return (idx >= pgd_index(GUARD_HOLE_BASE_ADDR)) &&
+ (idx < pgd_index(GUARD_HOLE_END_ADDR));
#else
return false;
#endif
diff --git a/arch/x86/xen/mmu_pv.c b/arch/x86/xen/mmu_pv.c
index b33fa127a613..7631e6130d44 100644
--- a/arch/x86/xen/mmu_pv.c
+++ b/arch/x86/xen/mmu_pv.c
@@ -614,19 +614,20 @@ static int __xen_pgd_walk(struct mm_struct *mm, pgd_t *pgd,
unsigned long limit)
{
int i, nr, flush = 0;
- unsigned hole_low, hole_high;
+ unsigned hole_low = 0, hole_high = 0;
/* The limit is the last byte to be touched */
limit--;
BUG_ON(limit >= FIXADDR_TOP);
+#ifdef CONFIG_X86_64
/*
* 64-bit has a great big hole in the middle of the address
- * space, which contains the Xen mappings. On 32-bit these
- * will end up making a zero-sized hole and so is a no-op.
+ * space, which contains the Xen mappings.
*/
- hole_low = pgd_index(USER_LIMIT);
- hole_high = pgd_index(PAGE_OFFSET);
+ hole_low = pgd_index(GUARD_HOLE_BASE_ADDR);
+ hole_high = pgd_index(GUARD_HOLE_END_ADDR);
+#endif
nr = pgd_index(limit) + 1;
for (i = 0; i < nr; i++) {