Re: [PATCH 0/2] ACPI: return error in acpi_pci_irq_enable when there is no irq

[Heikki Krogerus <heikki.krogerus@linux.intel.com>]

Hi,

On Mon, Sep 16, 2013 at 10:40:00AM +0300, Heikki Krogerus wrote:
> On Fri, Sep 13, 2013 at 05:55:40PM -0600, Bjorn Helgaas wrote:
> > On Fri, Sep 13, 2013 at 5:43 PM, Rafael J. Wysocki <rjw@sisk.pl> wrote:
> > > On Friday, September 13, 2013 08:52:18 AM Prarit Bhargava wrote:
> > >>
> > >> Rafael, is this in your queue?
> > >
> > > No, it is not, because Bjorn wanted to debug this issue deeper as far as I
> > > could understand.
> > >
> > > Bjorn?
> > 
> > Yes.  Yinghai pointed out a possible issue ("some USB3 host controller
> > does not have intx configured, but still work with MSI?").  I can't
> > explain to you right now what that means, but I did look at it enough
> > to think that there indeed might be a problem there.
> > 
> > So I asked [1] for a bugzilla with more info (dmesg, acpidump) so
> > somebody could look at it.  Actually, I was hoping Heikki or Prarit
> > would look into it and address Yinghai's concern.  Maybe there's no
> > problem there, but we should at least look and explain *why* it's not
> > a problem.  And I would really like a kernel.org bugzilla with the
> > info, in case this change turns out to have unintended consequences
> > and we have to debug it again later.
> 
> I'll ask Sarah (xHCI maintaner) for help in case she knows something
> and create a bug for this if needed.
> 
> I don't understand much about PCI, I need to study it a bit. Why would
> it be a problem to get the xHCI working with only MSI?

Sorry but I'll take it back. I don't understand the problem, so I
can't really file a bug.

Just in case there is a misunderstanding, I'll explain the situation
again. Right now there is no issue with xHCI controller driver. Prarit
has Dell machine that apparently has buggy BIOS. He suggested a WA [1]
for his issue, but that WA broke the xHCI on my Haswell machine. This
patch fixed his issue and left my xHCI controller working.

Maybe it would make sense to create a bug for the original issue with
the buggy BIOS on Prarit's Dell. Prarit, you need to file that one!

[1] http://permalink.gmane.org/gmane.linux.kernel.pci/23962

-- 
heikki