--- zzzz-none-000/linux-3.10.107/arch/arm/mm/pgd.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/arch/arm/mm/pgd.c	2021-02-04 17:41:59.000000000 +0000
@@ -11,6 +11,7 @@
 #include <linux/gfp.h>
 #include <linux/highmem.h>
 #include <linux/slab.h>
+#include <linux/kasan.h>
 
 #include <asm/cp15.h>
 #include <asm/pgalloc.h>
@@ -23,7 +24,7 @@
 #define __pgd_alloc()	kmalloc(PTRS_PER_PGD * sizeof(pgd_t), GFP_KERNEL)
 #define __pgd_free(pgd)	kfree(pgd)
 #else
-#define __pgd_alloc()	(pgd_t *)__get_free_pages(GFP_KERNEL, 2)
+#define __pgd_alloc()	(pgd_t *)__get_free_pages(GFP_KERNEL | __GFP_REPEAT, 2)
 #define __pgd_free(pgd)	free_pages((unsigned long)pgd, 2)
 #endif
 
@@ -64,6 +65,13 @@
 	new_pmd = pmd_alloc(mm, new_pud, 0);
 	if (!new_pmd)
 		goto no_pmd;
+
+#ifdef CONFIG_KASAN
+        memcpy(new_pmd + pmd_index(KASAN_SHADOW_START),
+               pmd_off_k(KASAN_SHADOW_START),
+               ((KASAN_SHADOW_END - KASAN_SHADOW_START)/PMD_SIZE)*sizeof(pmd_t));
+	clean_dcache_area(new_pmd, PTRS_PER_PMD * sizeof(pmd_t));
+#endif
 #endif
 
 	if (!vectors_high()) {
@@ -84,6 +92,16 @@
 		if (!new_pte)
 			goto no_pte;
 
+#ifndef CONFIG_ARM_LPAE
+		/*
+		 * Modify the PTE pointer to have the correct domain.  This
+		 * needs to be the vectors domain to avoid the low vectors
+		 * being unmapped.
+		 */
+		pmd_val(*new_pmd) &= ~PMD_DOMAIN_MASK;
+		pmd_val(*new_pmd) |= PMD_DOMAIN(DOMAIN_VECTORS);
+#endif
+
 		init_pud = pud_offset(init_pgd, 0);
 		init_pmd = pmd_offset(init_pud, 0);
 		init_pte = pte_offset_map(init_pmd, 0);
@@ -97,6 +115,7 @@
 
 no_pte:
 	pmd_free(mm, new_pmd);
+	mm_dec_nr_pmds(mm);
 no_pmd:
 	pud_free(mm, new_pud);
 no_pud:
@@ -130,9 +149,11 @@
 	pte = pmd_pgtable(*pmd);
 	pmd_clear(pmd);
 	pte_free(mm, pte);
+	atomic_long_dec(&mm->nr_ptes);
 no_pmd:
 	pud_clear(pud);
 	pmd_free(mm, pmd);
+	mm_dec_nr_pmds(mm);
 no_pud:
 	pgd_clear(pgd);
 	pud_free(mm, pud);
@@ -152,6 +173,7 @@
 		pmd = pmd_offset(pud, 0);
 		pud_clear(pud);
 		pmd_free(mm, pmd);
+		mm_dec_nr_pmds(mm);
 		pgd_clear(pgd);
 		pud_free(mm, pud);
 	}