This patch prepares a shadow area for KASAN.
The shadow area will be at the top of the kernel virtual
memory space above the fixmap area and will occupy one
eighth of the total kernel virtual memory space.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
depends on DEBUG_KERNEL && PPC_BOOK3S_64
help
If you're unsure what this is, say N.
+
+config KASAN_SHADOW_OFFSET
+ hex
+ depends on KASAN
+ default 0xe0000000
#include <asm/kmap_types.h>
#endif
+#ifdef CONFIG_KASAN
+#include <asm/kasan.h>
+#define FIXADDR_TOP (KASAN_SHADOW_START - PAGE_SIZE)
+#else
#define FIXADDR_TOP ((unsigned long)(-PAGE_SIZE))
+#endif
/*
* Here we define all the compile-time 'special' virtual
#define EXPORT_SYMBOL_KASAN(fn)
#endif
+#ifndef __ASSEMBLY__
+
+#include <asm/page.h>
+
+#define KASAN_SHADOW_SCALE_SHIFT 3
+
+#define KASAN_SHADOW_START (KASAN_SHADOW_OFFSET + \
+ (PAGE_OFFSET >> KASAN_SHADOW_SCALE_SHIFT))
+
+#define KASAN_SHADOW_OFFSET ASM_CONST(CONFIG_KASAN_SHADOW_OFFSET)
+
+#define KASAN_SHADOW_END 0UL
+
+#define KASAN_SHADOW_SIZE (KASAN_SHADOW_END - KASAN_SHADOW_START)
+
+#endif /* __ASSEMBLY */
#endif
mem_init_print_info(NULL);
#ifdef CONFIG_PPC32
pr_info("Kernel virtual memory layout:\n");
+#ifdef CONFIG_KASAN
+ pr_info(" * 0x%08lx..0x%08lx : kasan shadow mem\n",
+ KASAN_SHADOW_START, KASAN_SHADOW_END);
+#endif
pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP);
#ifdef CONFIG_HIGHMEM
pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n",
#endif
{ 0, "Fixmap start" },
{ 0, "Fixmap end" },
+#endif
+#ifdef CONFIG_KASAN
+ { 0, "kasan shadow mem start" },
+ { 0, "kasan shadow mem end" },
#endif
{ -1, NULL },
};
#endif
address_markers[i++].start_address = FIXADDR_START;
address_markers[i++].start_address = FIXADDR_TOP;
+#ifdef CONFIG_KASAN
+ address_markers[i++].start_address = KASAN_SHADOW_START;
+ address_markers[i++].start_address = KASAN_SHADOW_END;
+#endif
#endif /* CONFIG_PPC64 */
}