1 files changed, 38 insertions, 50 deletions

diff --git a/arch/powerpc/mm/kasan/kasan_init_32.c b/arch/powerpc/mm/kasan/kasan_init_32.c
index cbcad369fcb2..c42085801c04 100644
--- a/arch/powerpc/mm/kasan/kasan_init_32.c
+++ b/arch/powerpc/mm/kasan/kasan_init_32.c
@@ -5,9 +5,7 @@
 #include <linux/kasan.h>
 #include <linux/printk.h>
 #include <linux/memblock.h>
-#include <linux/moduleloader.h>
 #include <linux/sched/task.h>
-#include <linux/vmalloc.h>
 #include <asm/pgalloc.h>
 #include <asm/code-patching.h>
 #include <mm/mmu_decl.h>
@@ -30,40 +28,31 @@ static void __init kasan_populate_pte(pte_t *ptep, pgprot_t prot)
 		__set_pte_at(&init_mm, va, ptep, pfn_pte(PHYS_PFN(pa), prot), 0);
 }
 
-static int __init kasan_init_shadow_page_tables(unsigned long k_start, unsigned long k_end)
+int __init kasan_init_shadow_page_tables(unsigned long k_start, unsigned long k_end)
 {
 	pmd_t *pmd;
 	unsigned long k_cur, k_next;
-	pte_t *new = NULL;
 
 	pmd = pmd_ptr_k(k_start);
 
 	for (k_cur = k_start; k_cur != k_end; k_cur = k_next, pmd++) {
+		pte_t *new;
+
 		k_next = pgd_addr_end(k_cur, k_end);
 		if ((void *)pmd_page_vaddr(*pmd) != kasan_early_shadow_pte)
 			continue;
 
-		if (!new)
-			new = memblock_alloc(PTE_FRAG_SIZE, PTE_FRAG_SIZE);
+		new = memblock_alloc(PTE_FRAG_SIZE, PTE_FRAG_SIZE);
 
 		if (!new)
 			return -ENOMEM;
 		kasan_populate_pte(new, PAGE_KERNEL);
-
-		smp_wmb(); /* See comment in __pte_alloc */
-
-		spin_lock(&init_mm.page_table_lock);
-			/* Has another populated it ? */
-		if (likely((void *)pmd_page_vaddr(*pmd) == kasan_early_shadow_pte)) {
-			pmd_populate_kernel(&init_mm, pmd, new);
-			new = NULL;
-		}
-		spin_unlock(&init_mm.page_table_lock);
+		pmd_populate_kernel(&init_mm, pmd, new);
 	}
 	return 0;
 }
 
-static int __init kasan_init_region(void *start, size_t size)
+int __init __weak kasan_init_region(void *start, size_t size)
 {
 	unsigned long k_start = (unsigned long)kasan_mem_to_shadow(start);
 	unsigned long k_end = (unsigned long)kasan_mem_to_shadow(start + size);
@@ -76,75 +65,63 @@ static int __init kasan_init_region(void *start, size_t size)
 		return ret;
 
 	block = memblock_alloc(k_end - k_start, PAGE_SIZE);
+	if (!block)
+		return -ENOMEM;
 
 	for (k_cur = k_start & PAGE_MASK; k_cur < k_end; k_cur += PAGE_SIZE) {
 		pmd_t *pmd = pmd_ptr_k(k_cur);
 		void *va = block + k_cur - k_start;
 		pte_t pte = pfn_pte(PHYS_PFN(__pa(va)), PAGE_KERNEL);
 
-		if (!va)
-			return -ENOMEM;
-
 		__set_pte_at(&init_mm, k_cur, pte_offset_kernel(pmd, k_cur), pte, 0);
 	}
 	flush_tlb_kernel_range(k_start, k_end);
 	return 0;
 }
 
-static void __init kasan_remap_early_shadow_ro(void)
+void __init
+kasan_update_early_region(unsigned long k_start, unsigned long k_end, pte_t pte)
 {
-	pgprot_t prot = kasan_prot_ro();
-	unsigned long k_start = KASAN_SHADOW_START;
-	unsigned long k_end = KASAN_SHADOW_END;
 	unsigned long k_cur;
 	phys_addr_t pa = __pa(kasan_early_shadow_page);
 
-	kasan_populate_pte(kasan_early_shadow_pte, prot);
-
-	for (k_cur = k_start & PAGE_MASK; k_cur != k_end; k_cur += PAGE_SIZE) {
+	for (k_cur = k_start; k_cur != k_end; k_cur += PAGE_SIZE) {
 		pmd_t *pmd = pmd_ptr_k(k_cur);
 		pte_t *ptep = pte_offset_kernel(pmd, k_cur);
 
 		if ((pte_val(*ptep) & PTE_RPN_MASK) != pa)
 			continue;
 
-		__set_pte_at(&init_mm, k_cur, ptep, pfn_pte(PHYS_PFN(pa), prot), 0);
+		__set_pte_at(&init_mm, k_cur, ptep, pte, 0);
 	}
-	flush_tlb_kernel_range(KASAN_SHADOW_START, KASAN_SHADOW_END);
+
+	flush_tlb_kernel_range(k_start, k_end);
 }
 
-static void __init kasan_unmap_early_shadow_vmalloc(void)
+static void __init kasan_remap_early_shadow_ro(void)
 {
-	unsigned long k_start = (unsigned long)kasan_mem_to_shadow((void *)VMALLOC_START);
-	unsigned long k_end = (unsigned long)kasan_mem_to_shadow((void *)VMALLOC_END);
-	unsigned long k_cur;
+	pgprot_t prot = kasan_prot_ro();
 	phys_addr_t pa = __pa(kasan_early_shadow_page);
 
-	for (k_cur = k_start & PAGE_MASK; k_cur < k_end; k_cur += PAGE_SIZE) {
-		pmd_t *pmd = pmd_offset(pud_offset(pgd_offset_k(k_cur), k_cur), k_cur);
-		pte_t *ptep = pte_offset_kernel(pmd, k_cur);
+	kasan_populate_pte(kasan_early_shadow_pte, prot);
 
-		if ((pte_val(*ptep) & PTE_RPN_MASK) != pa)
-			continue;
+	kasan_update_early_region(KASAN_SHADOW_START, KASAN_SHADOW_END,
+				  pfn_pte(PHYS_PFN(pa), prot));
+}
 
-		__set_pte_at(&init_mm, k_cur, ptep, __pte(0), 0);
-	}
-	flush_tlb_kernel_range(k_start, k_end);
+static void __init kasan_unmap_early_shadow_vmalloc(void)
+{
+	unsigned long k_start = (unsigned long)kasan_mem_to_shadow((void *)VMALLOC_START);
+	unsigned long k_end = (unsigned long)kasan_mem_to_shadow((void *)VMALLOC_END);
+
+	kasan_update_early_region(k_start, k_end, __pte(0));
 }
 
-void __init kasan_mmu_init(void)
+static void __init kasan_mmu_init(void)
 {
 	int ret;
 	struct memblock_region *reg;
 
-	if (early_mmu_has_feature(MMU_FTR_HPTE_TABLE) ||
-	    IS_ENABLED(CONFIG_KASAN_VMALLOC)) {
-		ret = kasan_init_shadow_page_tables(KASAN_SHADOW_START, KASAN_SHADOW_END);
-
-		if (ret)
-			panic("kasan: kasan_init_shadow_page_tables() failed");
-	}
-
 	for_each_memblock(memory, reg) {
 		phys_addr_t base = reg->base;
 		phys_addr_t top = min(base + reg->size, total_lowmem);
@@ -156,10 +133,21 @@ void __init kasan_mmu_init(void)
 		if (ret)
 			panic("kasan: kasan_init_region() failed");
 	}
+
+	if (early_mmu_has_feature(MMU_FTR_HPTE_TABLE) ||
+	    IS_ENABLED(CONFIG_KASAN_VMALLOC)) {
+		ret = kasan_init_shadow_page_tables(KASAN_SHADOW_START, KASAN_SHADOW_END);
+
+		if (ret)
+			panic("kasan: kasan_init_shadow_page_tables() failed");
+	}
+
 }
 
 void __init kasan_init(void)
 {
+	kasan_mmu_init();
+
 	kasan_remap_early_shadow_ro();
 
 	clear_page(kasan_early_shadow_page);