Re: PCI driver module unload race?

[Patrick Mochel]

> > > I think it's not easy. I haven't studied the code completely yet, but
> > > e.g. when you attach a device to a driver you also have to get a
> > > reference to the driver.
> >
> > You get a link to the driver, but you can't increment the module count
> > of the driver at that time, as we have to be able to remove a module
> > somehow :)
> 
> That is simple. Export a generic way to disconnect a driver from a device.

It's not that easy - Linux has always supported the operation of being
able to remove a module while it is attached to devices. The reference
count only goes up if a device is opened. 

This means the module refcount must remain at 0, even after it's bound to 
devices. Changing this would require a change in visible behavior, and 
require an extra step by a user to disconnect the driver before they 
unload the module. 

	-pat