Re: [PATCH] pci: enable MSI on 8132

Andrew Morton
2009-02-18T19:15:10Z

On Wed, 18 Feb 2009 18:38:04 +0000
James Bottomley <James.Bottomley@HansenPartnership.com> wrote:

> On Wed, 2009-02-18 at 10:04 -0800, Andrew Morton wrote:
> > On Wed, 18 Feb 2009 04:27:28 -0800 (PST) david@lang.hm wrote:
> >
> > > On Wed, 18 Feb 2009, Matthew Wilcox wrote:
> > >
> > > > On Tue, Feb 17, 2009 at 08:40:09PM -0800, Yinghai Lu wrote:
> > > >>
> > > >> Impact: workaround BIOS that doesn't enable that bit
> > > >>
> > > >> David reported that LSI sas doesn't work with MSI.
> > > >> it turns out that BIOS doesn't enable HT MSI
> > > >> 8132 does support HT MSI.
> > > >> add quirk to enable it
> > > >>
> > > >> Reported-by: David Lang <david@lang.hm>
> > > >> Signed-off-by: Yinghai Lu <yinghai@kernel.org>
> > > >
> > > > Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
> > > >
> > > > Jesse, I think this should go into Linus' tree sooner rather than later.
> > >
> > > please forward to -stable as well. this is a regression since the card
> > > works with older kernels.
> > >
> >
> > Which kernel version introduced the regression?
>
> Technically, it's not a regression. The MSI problem has always been
> there, it was just exposed when the SAS card switched to using MSI by
> default. It's fixed by the bridge quirk ... of course it's unclear how
> many more bridges with problems there are.
>
> > Do we not need mpt-fix-enable-lsi-sas-to-use-msi-as-default.patch as
> > well, to fix this regression?
>
> No ... it's a separate issue. MSI was enabled for fusion SAS in 2.6.26;
> the problem msi patch which the above corrects actually has the effect
> of disabling MSI for fusion and went into 2.6.29-rc2, which isn't a
> kernel that's been tested here.

<scratches head>

So it should be the case that _either_ of
mpt-fix-enable-lsi-sas-to-use-msi-as-default.patch and
pci-enable-msi-on-8132.patch would fix David's machine?