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Diffstat (limited to 'arch/x86/mm/fault.c')
-rw-r--r--arch/x86/mm/fault.c66
1 files changed, 57 insertions, 9 deletions
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 428e31763cb9..8ad91a01cbc8 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -253,6 +253,7 @@ static inline pmd_t *vmalloc_sync_one(pgd_t *pgd, unsigned long address)
{
unsigned index = pgd_index(address);
pgd_t *pgd_k;
+ p4d_t *p4d, *p4d_k;
pud_t *pud, *pud_k;
pmd_t *pmd, *pmd_k;
@@ -265,10 +266,15 @@ static inline pmd_t *vmalloc_sync_one(pgd_t *pgd, unsigned long address)
/*
* set_pgd(pgd, *pgd_k); here would be useless on PAE
* and redundant with the set_pmd() on non-PAE. As would
- * set_pud.
+ * set_p4d/set_pud.
*/
- pud = pud_offset(pgd, address);
- pud_k = pud_offset(pgd_k, address);
+ p4d = p4d_offset(pgd, address);
+ p4d_k = p4d_offset(pgd_k, address);
+ if (!p4d_present(*p4d_k))
+ return NULL;
+
+ pud = pud_offset(p4d, address);
+ pud_k = pud_offset(p4d_k, address);
if (!pud_present(*pud_k))
return NULL;
@@ -384,6 +390,8 @@ static void dump_pagetable(unsigned long address)
{
pgd_t *base = __va(read_cr3());
pgd_t *pgd = &base[pgd_index(address)];
+ p4d_t *p4d;
+ pud_t *pud;
pmd_t *pmd;
pte_t *pte;
@@ -392,7 +400,9 @@ static void dump_pagetable(unsigned long address)
if (!low_pfn(pgd_val(*pgd) >> PAGE_SHIFT) || !pgd_present(*pgd))
goto out;
#endif
- pmd = pmd_offset(pud_offset(pgd, address), address);
+ p4d = p4d_offset(pgd, address);
+ pud = pud_offset(p4d, address);
+ pmd = pmd_offset(pud, address);
printk(KERN_CONT "*pde = %0*Lx ", sizeof(*pmd) * 2, (u64)pmd_val(*pmd));
/*
@@ -425,6 +435,7 @@ void vmalloc_sync_all(void)
static noinline int vmalloc_fault(unsigned long address)
{
pgd_t *pgd, *pgd_ref;
+ p4d_t *p4d, *p4d_ref;
pud_t *pud, *pud_ref;
pmd_t *pmd, *pmd_ref;
pte_t *pte, *pte_ref;
@@ -448,17 +459,37 @@ static noinline int vmalloc_fault(unsigned long address)
if (pgd_none(*pgd)) {
set_pgd(pgd, *pgd_ref);
arch_flush_lazy_mmu_mode();
- } else {
+ } else if (CONFIG_PGTABLE_LEVELS > 4) {
+ /*
+ * With folded p4d, pgd_none() is always false, so the pgd may
+ * point to an empty page table entry and pgd_page_vaddr()
+ * will return garbage.
+ *
+ * We will do the correct sanity check on the p4d level.
+ */
BUG_ON(pgd_page_vaddr(*pgd) != pgd_page_vaddr(*pgd_ref));
}
+ /* With 4-level paging, copying happens on the p4d level. */
+ p4d = p4d_offset(pgd, address);
+ p4d_ref = p4d_offset(pgd_ref, address);
+ if (p4d_none(*p4d_ref))
+ return -1;
+
+ if (p4d_none(*p4d)) {
+ set_p4d(p4d, *p4d_ref);
+ arch_flush_lazy_mmu_mode();
+ } else {
+ BUG_ON(p4d_pfn(*p4d) != p4d_pfn(*p4d_ref));
+ }
+
/*
* Below here mismatches are bugs because these lower tables
* are shared:
*/
- pud = pud_offset(pgd, address);
- pud_ref = pud_offset(pgd_ref, address);
+ pud = pud_offset(p4d, address);
+ pud_ref = pud_offset(p4d_ref, address);
if (pud_none(*pud_ref))
return -1;
@@ -526,6 +557,7 @@ static void dump_pagetable(unsigned long address)
{
pgd_t *base = __va(read_cr3() & PHYSICAL_PAGE_MASK);
pgd_t *pgd = base + pgd_index(address);
+ p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
@@ -538,7 +570,15 @@ static void dump_pagetable(unsigned long address)
if (!pgd_present(*pgd))
goto out;
- pud = pud_offset(pgd, address);
+ p4d = p4d_offset(pgd, address);
+ if (bad_address(p4d))
+ goto bad;
+
+ printk("P4D %lx ", p4d_val(*p4d));
+ if (!p4d_present(*p4d) || p4d_large(*p4d))
+ goto out;
+
+ pud = pud_offset(p4d, address);
if (bad_address(pud))
goto bad;
@@ -1082,6 +1122,7 @@ static noinline int
spurious_fault(unsigned long error_code, unsigned long address)
{
pgd_t *pgd;
+ p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
@@ -1104,7 +1145,14 @@ spurious_fault(unsigned long error_code, unsigned long address)
if (!pgd_present(*pgd))
return 0;
- pud = pud_offset(pgd, address);
+ p4d = p4d_offset(pgd, address);
+ if (!p4d_present(*p4d))
+ return 0;
+
+ if (p4d_large(*p4d))
+ return spurious_fault_check(error_code, (pte_t *) p4d);
+
+ pud = pud_offset(p4d, address);
if (!pud_present(*pud))
return 0;