linux-kernel - Re: [Bug #15124] PCI host bridge windows ignored (works with pci=use

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20100127130210.6fe94255@jbarnes-piketon>
Date:	Wed, 27 Jan 2010 13:02:10 -0800
From:	Jesse Barnes <jbarnes@...tuousgeek.org>
To:	Jesse Barnes <jbarnes@...tuousgeek.org>
Cc:	Linus Torvalds <torvalds@...ux-foundation.org>,
	Bjorn Helgaas <bjorn.helgaas@...com>,
	Yinghai Lu <yinghai@...nel.org>,
	Jeff Garrett <jeff@...rrett.org>,
	"Rafael J. Wysocki" <rjw@...k.pl>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Kernel Testers List <kernel-testers@...r.kernel.org>,
	Linux PCI <linux-pci@...r.kernel.org>,
	Myron Stowe <myron.stowe@...com>,
	Matthew Garrett <mjg59@...f.ucam.org>,
	Ingo Molnar <mingo@...e.hu>
Subject: Re: [Bug #15124] PCI host bridge windows ignored (works with
 pci=use_crs)

On Wed, 27 Jan 2010 12:59:05 -0800
Jesse Barnes <jbarnes@...tuousgeek.org> wrote:

> On Wed, 27 Jan 2010 12:50:12 -0800 (PST)
> Linus Torvalds <torvalds@...ux-foundation.org> wrote:
> 
> > 
> > 
> > On Wed, 27 Jan 2010, Bjorn Helgaas wrote:
> > > 
> > > Without intel_bus.c, we essentially assume config 1 all the time.
> > > If we keep intel_bus.c and this patch for .33, things should work
> > > for configs 1 and 4.  Adding support for config 4 is good.
> > 
> > Quite frankly, is there any major downside to just disabling/removing 
> > intel_bus.c for 2.6.33? If we're not planning on having it in the long run 
> > anyway - or even if we are, but we can't be really happy about the state 
> > of it as it would be in 2.6.33, not using it at all seems to be the 
> > smaller headache.
> > 
> > The machines that it helps are also the machines where you can fix things 
> > up with 'use_csr', no? And they are pretty rare, and they didn't use to 
> > work without that use_csr in 2.6.32 either, so it's not even a regression.
> > 
> > Am I missing something?
> 
> No that's the plan.  intel_bus.c was a good effort, but it's just too
> different from what Windows does, and it'll always be behind.  We'll
> disable it for 2.6.33 and try again to move to _CRS in 2.6.34 (but
> fixing the problem with large numbers of _CRS resources this time).

Should say "disable it for 2.6.33 for all but multi-IOH configs", which
seem to be fairly rare anyway, and were what intel_bus.c was designed
to accommodate.  On the one machine that motivated it, use_crs was
broken (though it likely isn't now), so it seems the safest route.

-- 
Jesse Barnes, Intel Open Source Technology Center
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/