This fixes a couple of compiler warnings, and adds paranoia checks as well.
Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
        image = xchg(dest_image, image);
 
 out:
-       xchg(&kexec_lock, 0); /* Release the mutex */
+       locked = xchg(&kexec_lock, 0); /* Release the mutex */
+       BUG_ON(!locked);
        kimage_free(image);
 
        return result;
                        machine_crash_shutdown(&fixed_regs);
                        machine_kexec(kexec_crash_image);
                }
-               xchg(&kexec_lock, 0);
+               locked = xchg(&kexec_lock, 0);
+               BUG_ON(!locked);
        }
 }