kasan-for-arm32

[李文杰]

Dear Linus Walleij,

1. I know why my machine crash after porting the patch.
2. Because the kernel access the vmalloc region, which not shadowed.
3. Now I found at least two places where used vmalloc region:
   1). arch/arm/mm/fault-armv.c ->check_writebuffer_bugs() -> vmap();
   2). lib/genalloc.c -> chunk = vzalloc_node(nbytes, nid);
4. could I add the vmalloc to shadow memory region?

Thanks very much.