static unsigned long doublefault_stack[DOUBLEFAULT_STACKSIZE];
#define STACK_START (unsigned long)(doublefault_stack+DOUBLEFAULT_STACKSIZE)
-#define ptr_ok(x) ((x) > 0xc0000000 && (x) < 0xc1000000)
+#define ptr_ok(x) ((x) > PAGE_OFFSET && (x) < PAGE_OFFSET + 0x1000000)
static void doublefault_fn(void)
{