Re: [PATCH] libata: fix use-after-free during driver unload/unplug

[Mark Lord <liml@rtr.ca>]

Jeff Garzik wrote:
>
> qstor's ->host_stop() disables global interrupts, and I didn't know if 
> you really wanted to do that prior to ->port_stop().
> 
> I would much prefer to eliminate the ->host_stop_prewalk() hook, and 
> simply call ->host_stop after all ->port_stop() calls complete, if qstor 
> doesn't need the pre-walk.

Ahh.. of course.  I must have misread your original.

Yes, sata_qstor generally assumes that host_stop should completely
stop the host from operating.. and thereby expects any port_stop()
calls to happen before host_stop().  So, yup, the changes you have
seem to be useful here.

If we didn't want to have a prewalk() method, then we could hack
sata_qstor to keep a count of active ("non stopped") ports,
and automatically do the global (chip) interrupt disable from
port_stop() whenever the count hits zero.

Cheers