[PATCH/RFC] PCI Error Recovery

[Benjamin Herrenschmidt]

> Perhaps, but Linas' version seems to be far too PPC64 centric to me.
> 
> It's really not in your interest either to have a too ppc64 specific
> solution because it means much additional work to fix drivers for
> ppc64 that have been developed on other architectures. 
> 
> What's wrong with just simply telling the driver.
> 
> an error occurred. all your recent transactions may be broken.
> To use the device again call "foo" first to fix the device.
> foo then returns if it fixed the device or not.

I want something along those lines, except that I wnat it asynchronous
because of the issue of drivers sharing the same bus segment that need
to be all notifed before we can re-enable things. Also, I can either
just re-enable IOs, re-enable DMA, both, reset the slot, etc....

I may not offer that rich functionality in the generic API, but I need
to find the right "cutting point". Just re-enabling IOs is useful for
drivers who can extract diagnostic infos from the device, for example
after a DMA error. Resetting the slot may be necessary to get some
devices back.

> I don't get why the driver even needs to know about isolation
> or not. It's not fundamentally different from an bus abort
> on other systems, just that it lasts longer.