Re: [PATCH v6 00/10] PCI: Fix unhandled interrupt on shutdown

[Bjorn Helgaas <bhelgaas@google.com>]

On Sun, Apr 26, 2015 at 08:50:06AM +0200, Michael S. Tsirkin wrote:
> On Fri, Apr 10, 2015 at 05:54:19PM -0500, Bjorn Helgaas wrote:
> > Hi Michael,
> > 
> > I put your patches on my pci/msi branch and I hope to merge them for v4.1.
> > I didn't apply the acks from Fam and Eric because I made changes to those
> > patches that weren't completely trivial.  I think the end result is
> > equivalent, though.  The diff attached to this cover letter is the
> > difference between your v5 series and this v6 series.
> > 
> > As far as I'm concerned, this is ready to go except that I would like a
> > little more info about the virtio kernel hang to include in the changelog
> > for "PCI/MSI: Don't disable MSI/MSI-X at shutdown".
> 
> 
> Hi Bjorn,
> do you have eveything you need to merge this?

No.  I made the minor changelog edits you suggested and the result is on
my pci/msi-v7 branch.  But I still have these open issues:

  - The last thing I heard from Eric was that "not disabling MSI/MSI-X at
    shutdown is the wrong fix, and someone needs to fix a buggy driver."
    I want to hear Eric say "OK, we need to leave MSI/MSI-X enabled at
    shutdown for this case."

  - One changelog says "Stop disabling MSIs at shutdown to avoid
    conflicting with drivers."  But I don't know what the conflict is.

  - The bugzilla has no dmesg log or detailed analysis.  Fam said the
    scenario I came up with
    (http://lkml.kernel.org/r/20150416194245.GB20701@google.com)
    was fairly close, but it took me a lot of work to derive that.  Fixing
    any errors in it and putting it in the bugzilla would be a big step.
    The bugzilla should have the raw data and the analysis, so someone else
    can validate the analysis and conclude that this patch is a reasonable
    fix for it.  That's currently impossible because the bugzilla really
    only contains the fix as a fait accompli.

Bjorn