powerpc/kasan: Fix shadow pages allocation failure

chleroy · mpe · commit d2a91cef9bbd · 2020-05-20T23:41:02.000+10:00
Doing kasan pages allocation in MMU_init is too early, kernel doesn't have access yet to the entire memory space and memblock_alloc() fails when the kernel is a bit big. Do it from kasan_init() instead. Fixes: 2edb16e ("powerpc/32: Add KASAN support") Cc: stable@vger.kernel.org Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/c24163ee5d5f8cdf52fefa45055ceb35435b8f15.1589866984.git.christophe.leroy@csgroup.eu
diff --git a/arch/powerpc/include/asm/kasan.h b/arch/powerpc/include/asm/kasan.h
@@ -27,12 +27,10 @@
 
 #ifdef CONFIG_KASAN
 void kasan_early_init(void);
-void kasan_mmu_init(void);
 void kasan_init(void);
 void kasan_late_init(void);
 #else
 static inline void kasan_init(void) { }
-static inline void kasan_mmu_init(void) { }
 static inline void kasan_late_init(void) { }
 #endif
 
diff --git a/arch/powerpc/mm/init_32.c b/arch/powerpc/mm/init_32.c
@@ -170,8 +170,6 @@ void __init MMU_init(void)
 	btext_unmap();
 #endif
 
-	kasan_mmu_init();
-
 	setup_kup();
 
 	/* Shortly after that, the entire linear mapping will be available */
diff --git a/arch/powerpc/mm/kasan/kasan_init_32.c b/arch/powerpc/mm/kasan/kasan_init_32.c
@@ -131,7 +131,7 @@ static void __init kasan_unmap_early_shadow_vmalloc(void)
 	flush_tlb_kernel_range(k_start, k_end);
 }
 
-void __init kasan_mmu_init(void)
+static void __init kasan_mmu_init(void)
 {
 	int ret;
 	struct memblock_region *reg;
@@ -159,6 +159,8 @@ void __init kasan_mmu_init(void)
 
 void __init kasan_init(void)
 {
+	kasan_mmu_init();
+
 	kasan_remap_early_shadow_ro();
 
 	clear_page(kasan_early_shadow_page);

Original file line number	Diff line number	Diff line change
`@@ -131,7 +131,7 @@ static void __init kasan_unmap_early_shadow_vmalloc(void)`
`131`	`131`	`flush_tlb_kernel_range(k_start, k_end);`
`132`	`132`	`}`
`133`	`133`
`134`		`-void __init kasan_mmu_init(void)`
	`134`	`+static void __init kasan_mmu_init(void)`
`135`	`135`	`{`
`136`	`136`	`int ret;`
`137`	`137`	`struct memblock_region *reg;`
`@@ -159,6 +159,8 @@ void __init kasan_mmu_init(void)`
`159`	`159`
`160`	`160`	`void __init kasan_init(void)`
`161`	`161`	`{`
	`162`	`+ kasan_mmu_init();`
	`163`	`+`
`162`	`164`	`kasan_remap_early_shadow_ro();`
`163`	`165`
`164`	`166`	`clear_page(kasan_early_shadow_page);`