Re: [PATCH][2.6][CFT] rmmod floppy kills box fixes + default_device_remove

[Zwane Mwaikambo]

On Tue, 9 Sep 2003, Zwane Mwaikambo wrote:

> > So an empty release() function is the wrong thing to do in 99.99% of the
> > situations in the kernel (the one exception seems to be the mca release
> > function that recently got added for use when the bus is doing probing
> > logic.)
> > 
> > Does this help out?
> 
> Yes thanks, i was confused over which memory references had to be 
> maintained.

Ok i had another look and i can see why you need a seperate release 
function, as we don't always do the kobject_cleanup immediately.

John and myself had a look and now we have the following race on 
->release() function exit.

my_release_fn()
{
	complete(&my_completion);
	<== [1] stall anywhere here, e.g. preempt/schedule
}

cleanup_module()
{
	wait_for_completion(&my_completion);
	<== [1] this task gets scheduled, free()s module text
}
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