Re: [PATCH] powerpc/pseries: Force 32 bit MSIs when tearing down

[Benjamin Herrenschmidt <benh@kernel.crashing.org>]

On Tue, 2013-05-28 at 09:20 +0200, Alexander Gordeev wrote:
> On Tue, May 28, 2013 at 07:52:11AM +1000, Benjamin Herrenschmidt wrote:
> > On Mon, 2013-05-27 at 18:20 +0200, Alexander Gordeev wrote:
> > > This fix just adds a missed call to a new PAPR function
> > > which should have been done with commit e61133d ("powerpc/
> > > pseries: Force 32 bit MSIs for devices that require it")
> > 
> > Arguably, PAPR should allow to disable MSIs using either interface,
> > we shouldn't have to know whether the MSI was a forced-32-bit one to be
> > able to disable it.
> 
> BTW, it is not clear why MSIs do not get disabled on powernv on teardown.
> Would this (pseudo-code) make sense?

Because we don't really have anything to do there. The MSI is just a normal
interrupt source in the PHB, so the "normal" disable_irq (part of free_irq)
will take care of masking it, and from there it's just returning it to the pool
of available interrupts (the bitmap) and removing the mapping.

Cheers,
Ben.