kmemcheck: don't track page tables

As these are allocated using the page allocator, we need to pass
__GFP_NOTRACK before we add page allocator support to kmemcheck.
Signed-off-by: NVegard Nossum <vegard.nossum@gmail.com>

arch/x86/mm/init_64.c

@@ -104,7 +104,7 @@ static __ref void *spp_getpage(void)
 	void *ptr;
 
 	if (after_bootmem)
-		ptr = (void *) get_zeroed_page(GFP_ATOMIC);
+		ptr = (void *) get_zeroed_page(GFP_ATOMIC | __GFP_NOTRACK);
 	else
 		ptr = alloc_bootmem_pages(PAGE_SIZE);
 
@@ -281,7 +281,7 @@ static __ref void *alloc_low_page(unsigned long *phys)
 	void *adr;
 
 	if (after_bootmem) {
-		adr = (void *)get_zeroed_page(GFP_ATOMIC);
+		adr = (void *)get_zeroed_page(GFP_ATOMIC | __GFP_NOTRACK);
 		*phys = __pa(adr);
 
 		return adr;

arch/x86/mm/pageattr.c

@@ -470,7 +470,7 @@ static int split_large_page(pte_t *kpte, unsigned long address)
 
 	if (!debug_pagealloc)
 		spin_unlock(&cpa_lock);
-	base = alloc_pages(GFP_KERNEL, 0);
+	base = alloc_pages(GFP_KERNEL | __GFP_NOTRACK, 0);
 	if (!debug_pagealloc)
 		spin_lock(&cpa_lock);
 	if (!base)

arch/x86/mm/pgtable.c

@@ -4,9 +4,11 @@
 #include <asm/tlb.h>
 #include <asm/fixmap.h>
 
+#define PGALLOC_GFP GFP_KERNEL | __GFP_NOTRACK | __GFP_REPEAT | __GFP_ZERO
+
 pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
 {
-	return (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
+	return (pte_t *)__get_free_page(PGALLOC_GFP);
 }
 
 pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
@@ -14,9 +16,9 @@ pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
 	struct page *pte;
 
 #ifdef CONFIG_HIGHPTE
-	pte = alloc_pages(GFP_KERNEL|__GFP_HIGHMEM|__GFP_REPEAT|__GFP_ZERO, 0);
+	pte = alloc_pages(PGALLOC_GFP | __GFP_HIGHMEM, 0);
 #else
-	pte = alloc_pages(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO, 0);
+	pte = alloc_pages(PGALLOC_GFP, 0);
 #endif
 	if (pte)
 		pgtable_page_ctor(pte);
@@ -161,7 +163,7 @@ static int preallocate_pmds(pmd_t *pmds[])
 	bool failed = false;
 
 	for(i = 0; i < PREALLOCATED_PMDS; i++) {
-		pmd_t *pmd = (pmd_t *)get_zeroed_page(GFP_KERNEL|__GFP_REPEAT);
+		pmd_t *pmd = (pmd_t *)__get_free_page(PGALLOC_GFP);
 		if (pmd == NULL)
 			failed = true;
 		pmds[i] = pmd;
@@ -228,7 +230,7 @@ pgd_t *pgd_alloc(struct mm_struct *mm)
 	pmd_t *pmds[PREALLOCATED_PMDS];
 	unsigned long flags;
 
-	pgd = (pgd_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
+	pgd = (pgd_t *)__get_free_page(PGALLOC_GFP);
 
 	if (pgd == NULL)
 		goto out;