The driver is in control of the show, so when you try and unload a module
the driver detach routine is called first. It is what drives the whole
unload process and so lots of panics occur if dev->driver is already
free.
me to match other drivers and avoid ifdeffing. The linux via_drv.c will
be moved from shared-core to linux-core soon by repocopy.
Submitted by: Jake Burkholder <jake@FreeBSD.org> Tested by: unichrome