Bug 38522

First-Bad-Commit : 5d94e81f69d4b1d1102d3ab557ce0a817c11fbbb

Trying to gather more details.  The "Component" field says i386, but was this a 64-bit build?  Otherwise I would expect this to have been a problem before this commit because the primary change of this patch was adding probe_roms to 64-bit builds.  I wonder if that hard coded Video ROM resource needs can be sanitized against the PNP resources?

it was a 64bit build yes sorry. I had just looked at the folder and assumed it was relating to both 32 and 64 bit architectures. I shall leave it to the experts ;-)

(In reply to comment #3)
> it was a 64bit build yes sorry. I had just looked at the folder and assumed
> it
> was relating to both 32 and 64 bit architectures. I shall leave it to the
> experts ;-)

Thanks for clarifying that's an important distinction.

Want to gather a bit more information.  If you have the time I believe it would be helpful to see if the same report happens with a 32-bit kernel build.  If it does then it seems the problem is more general with this platform, if it does not then maybe there is 32-bit code that needs to be promoted to santize the pnp resources?

same error message on i386 kernel. No log though I'm since I couldn't boot my 64 bit system with it, but unless I did something totally wrong, then this information is correct.

(In reply to comment #5)
> same error message on i386 kernel.

Ok, thanks, that confirms that it is a general problem.  I chatted with Bjorn and his opinion was that as long as the platform still operates the only real problem is the severity of the log message.  Does your platform otherwise operate ok?

Created attachment 64102 [details]
reduce message severity

Jools, can you try this patch and confirm whether you see any other issues?  Thanks!

*** Bug 16497 has been marked as a duplicate of this bug. ***

I probably should have mentioned in the initial report that everything seemed to be fine. So yeh, machine works fine. The patch hides the message on boot. All good thanks.

So the OPs message was this;

pci_root PNP0A08:00: address space collision: host bridge window
[mem 0x000c8000-0x000dffff] conflicts with Video ROM [mem
0x000c0000-0x000cdbff]

And this is mine;

pci_root PNP0A08:00: address space collision: host bridge window [mem 0x000cc000-0x000cffff] conflicts with Video ROM [mem 0x000c0000-0x000ce9ff]

So will that patch be fine for me to use too?


THANKS

Das, yes, the patch should be fine for everybody to use.

Hi Bjorn,

Ok I forget some of the patch cmds, so in the source directory I can run this?


patch -p0 </path/back/to/patch


THANKS

The patch above failed on me;


root@slackware:/usr/src/linux-2.6.36.4# patch -p1 </home/sar/Downloads/07-bz3852
patching file arch/x86/pci/acpi.c
Hunk #1 FAILED at 246.
1 out of 1 hunk FAILED -- saving rejects to file arch/x86/pci/acpi.c.rej


THANKS

The patch isn't going to change any behavior for you, other than removing the error message and maybe making the boot splash screen a little prettier.  If you really need to get rid of the message, you can just apply the patch by hand, i.e., edit arch/x86/pci/acpi.c with a text editor.

I understand what the patch is for, but isn't the cmd if I'm in the source directory and run it;

patch -p1 </path/back/to/patch suppose to work?

I don't know what to edit if I did it by hand, just want to know if I'm running the cmd correct?

Been a while since I've patched anything and forgot the cmd...

THANKS

Created attachment 64932 [details]
edited acpi.c

Sorry forgot to make a comment but above is the edited acpi.c I changed by hand will this work now?


THANKS

Created attachment 64942 [details]
good-acpi.c?

Ok I did not understand patches before, the - lines which are 4 get removed is all and the + lines which are 3 replace the 4 that are removed so now I added in what I was told is a correct file.

Please tell me now if the good-acpic.c? I uploaded is good?


THANKS

It doesn't work I'm still getting the message in dmesg;

pci_root PNP0A08:00: ignoring host bridge window [mem 0x000cc000-0x000cffff] (conflicts with Video ROM [mem 0x000c0000-0x000ce9ff])

So should I just use "pci=nocrs"

Or can I get a working patch for 2.6.36.4?


THANKS

I think the devs may well be busy enough without having to tutorial users on stuff like this. Either wait for the patched kernel, apply the patch to a newer kernel, or ignore the message.

On Monday, July 11, 2011, Dan Williams wrote:
> [ adding Bjorn ]
> 
> On Sun, Jul 10, 2011 at 3:38 AM, Rafael J. Wysocki <rjw@sisk.pl> wrote:
> > This message has been generated automatically as a part of a summary report
> > of recent regressions.
> >
> > The following bug entry is on the current list of known regressions
> > from 2.6.39.  Please verify if it still should be listed and let the
> tracking team
> > know (either way).
> 
> The patch from the bugzilla entry is not yet upstream.
> 
> >
> > Bug-Entry       : http://bugzilla.kernel.org/show_bug.cgi?id=38522
> > Subject         : address space collision error message on boot
> > Submitter       : Jools Wills <jools@oxfordinspire.co.uk>
> > Date            : 2011-06-29 02:28 (12 days old)
> > First-Bad-Commit:
> http://git.kernel.org/linus/5d94e81f69d4b1d1102d3ab557ce0a817c11fbbb
> 
> Per the commentary in the bugzilla this commit makes the warning
> message appear on 64-bit builds, but 32-bit has the same problem on
> affected platforms (without the commit).
> 
> Bjorn has a proposed patch [1] that just downgrades the warning since
> system operation does not appear to be affected.
> 
> --
> Dan
> 
> [1]: https://bugzilla.kernel.org/attachment.cgi?id=64102

Patch: https://patchwork.kernel.org/patch/940442/

Sorry for the delay in responding; I was on vacation a few days.

Das, I think the file you attached in comment #18 is correct.  The line in dmesg that you mention in comment #19 is exactly what I expect.  It's merely informational; it does not mean anything is broken.  You should not need to use "pci=nocrs".

I tried running the patch with several different commands and it fails...

Then I edited it by hand and when I rebooted it didn't work...

A patch referencing this bug report has been merged in Linux v3.1-rc1:

commit 43d786ed4df4c54cb8802a523748a7d78130a2cb
Author: Bjorn Helgaas <bhelgaas@google.com>
Date:   Sat Jul 2 10:47:12 2011 -0600

    x86/PCI: reduce severity of host bridge window conflict warnings