=== build output (guest, instrumented module build) ===
cc ... -D_KERNEL ... -c uaudio_pcm.c
cc ... -D_KERNEL ... -c uaudio.c
-rw-r--r-- 1 root 1000 66208 uaudio.ko

=== fixed module build ===
-rw-r--r-- 1 root 1000 65872 uaudio.ko  (fix.diff applied, 0 errors)