x86/mm: Convert trivial cases of page table walk to 5-level paging
This patch only covers simple cases. Less trivial cases will be
converted with separate patches.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170313143309.16020-3-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 428e3176..605fd5e 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));
/*
@@ -526,6 +536,7 @@ 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 +549,15 @@ 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 +1101,7 @@ 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 +1124,14 @@ 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;