fault_in_readable
if (fault_in_readable((const char __user *)KVM_MAGIC_PAGE,
fault_in_readable((char __user *)new_ctx, ctx_size))
fault_in_readable((char __user *)ctx, sizeof(*ctx)))
fault_in_readable((char __user *)new_ctx, ctx_size))
if (!fault_in_readable(buf, fpu->fpstate->user_size))
if (fault_in_readable(ptr, args->size))
size_t fault_in_readable(const char __user *uaddr, size_t size);
n -= fault_in_readable(i->ubuf + i->iov_offset, n);
ret = fault_in_readable(p->iov_base + skip, len);
EXPORT_SYMBOL(fault_in_readable);