Re: Future of pci-mvebu

[Bjorn Helgaas <helgaas@kernel.org>]

On Tue, Jul 18, 2023 at 06:57:03PM +0200, Pali Rohár wrote:
> On Tuesday 18 July 2023 06:19:52 Bjorn Helgaas wrote:
> > On Tue, Jul 18, 2023 at 12:03:17AM +0200, Pali Rohár wrote:
> > > Hello, I have just one question. What do you want to do with pci-mvebu
> > > driver? It is already marked as broken for 3 kernel releases and I do
> > > not see any progress from anybody (and you rejected my fixes). How long
> > > do you want it to have marked as broken?
> > 
> > I don't think "depends on BROKEN" necessarily means that we plan to
> > remove the driver.  I think it just means that it's currently broken,
> > but we hope to fix it eventually.
> > 
> > I think the problem here is the regular vs chained interrupt handlers,
> > right?  Radu has been looking at that recently, too, so maybe we can
> > have another go at it.
> 
> I guess that this is the main issue as all other fixes and improvements
> are stalled. 

If these other things don't depend on this IRQ issue, maybe we could
still make progress on them?  Maybe post them again (rebasing to
v6.5-rc1 if necessary)?  Often I forget or miss things, so it doesn't
hurt to try again if you don't hear anything.

> Just to remind that we have there shared interrupt source
> (which can be requested by more HW drivers) and consumer is PCIe INTX
> which is de-facto chained handler. And I have not seen anything for
> shared interrupt source except request_irq(IRQF_SHARED) which you do not
> want to use for shared interrupts anymore. Also setting of PCIe INTX
> affinity is broken which worked fine with the previous kernel versions.
> And you also rejected fixes for this regression.

This sounds like the issue where we haven't figured out how to make
both Marc and Thomas happy at the same time.  I don't know much about
IRQs, but I'm still optimistic that it may be possible because I don't
think there's anything really unique about mvebu here.

Bjorn