ASM1083 PCIx-PCI bridge interrupts - widespread problems

From: Chris Palmer <chris.palmer@pobox.com>
To: torvalds@linux-foundation.org
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Len Brown <lenb@kernel.org>,
	ghost3k@ghost3k.net, linux-kernel@vger.kernel.org,
	hancockrwd@gmail.com, edward.donovan@numble.net, keve@irb.hu
Subject: ASM1083 PCIx-PCI bridge interrupts - widespread problems
Date: Mon, 30 Jan 2012 15:04:02 +0000	[thread overview]
Message-ID: <4F26B162.4050000@pobox.com> (raw)
In-Reply-To: <20110908165155.f661a738.akpm@linux-foundation.org>

Linus et al

For about 6 months many users have been having interrupt problems with PCI boards, but it hasn't been 
easy trying to find where the problem may be. However, it is now looking likely that the problem lies 
in the ASM1083 PCIe-PCI bridge chipset, as used by Asus in many Sandybridge and AMD boards.

My original bug report is:
    https://bugzilla.kernel.org/show_bug.cgi?id=38632  (Sandybridge)

and there several other similar ones. However there is also extensive investigation in the following thread:
    http://www.gossamer-threads.com/lists/linux/kernel/1466185  (AMD)

There have also been reports of Windows users having similar problems.

This problem prevents use of PCI boards in any motherboard with that bridge chipset - including most 
ASUS boards. At the moment though we don't know whether the chipset or drivers are faulty, and if a 
workaround is possible.

At the moment my bug is assigned to drivers_network, but this doesn't look appropriate.

Hoping someone can help...

Regards
Chris

On 09/09/2011 00:51, Andrew Morton wrote:

> On Thu, 08 Sep 2011 12:28:40 +0100
> Chris Palmer <chris.palmer@pobox.com> wrote:
>
>> Andrew
>>
>> I'm writing to ask if you could cast a quick eye over the following
>> bugs, to give an opinion on where they should be assigned. Mine has been
>> reassigned to Network Drivers but I'm not convinced that is right, and I
>> think the problem is wider than that.
>>
>> In summary, interrupt handling for *PCI boards with ASUS Sandybridge
>> motherboards* seems to be broken.
>>
>> It has been seen with network and non-network PCI boards. PCIx network
>> boards work OK. And all reports are for ASUS motherboards.
>>
>> My bug report is
>>
>> https://bugzilla.kernel.org/show_bug.cgi?id=38632
>>
>> Others that I know of are:
>>
>> https://bugzilla.redhat.com/show_bug.cgi?id=713351
>> https://bugzilla.kernel.org/show_bug.cgi?id=35332
>> https://bugzilla.kernel.org/show_bug.cgi?id=34242
>> https://bugzilla.kernel.org/show_bug.cgi?id=32242
>> https://bugzilla.kernel.org/show_bug.cgi?id=39122
>>
>>
>> I'm now on kernel 3.0.4 with the problem still there. The only thing
>> that seems to make a difference is acpi=off (although one person
>> reported that it merely changed it from minutes to days before occurring).
>>
>> I'd appreciate anything you could do to move this in the right direction...
>>
>
> Most likely ACPI, I expect.  I think that's
> acpi-config-interrupts@bugzilla.kernel.org.  kernel.org DNS is dead at
> present and I can't check.
>
> Len, can you suggest how to triage these please?