+ int cpu = get_cpu();
+ struct tss_struct *tss = &per_cpu(init_tss, cpu);
+ struct thread_struct *thread = ¤t->thread;
+
+ /*
+ * Perform the lazy TSS's I/O bitmap copy. If the TSS has an
+ * invalid offset set (the LAZY one) and the faulting thread has
+ * a valid I/O bitmap pointer, we copy the I/O bitmap in the TSS
+ * and we set the offset field correctly. Then we let the CPU to
+ * restart the faulting instruction.
+ */
+ if (tss->io_bitmap_base == INVALID_IO_BITMAP_OFFSET_LAZY &&
+ thread->io_bitmap_ptr) {
+ memcpy(tss->io_bitmap, thread->io_bitmap_ptr,
+ thread->io_bitmap_max);
+ /*
+ * If the previously set map was extending to higher ports
+ * than the current one, pad extra space with 0xff (no access).
+ */
+ if (thread->io_bitmap_max < tss->io_bitmap_max)
+ memset((char *) tss->io_bitmap +
+ thread->io_bitmap_max, 0xff,
+ tss->io_bitmap_max - thread->io_bitmap_max);
+ tss->io_bitmap_max = thread->io_bitmap_max;
+ tss->io_bitmap_base = IO_BITMAP_OFFSET;
+ put_cpu();
+ return;
+ }
+ put_cpu();
+