d0 Error pfn 100

d0 Error pfn 100

[Christoph Egger]

Hi!

I see these messages from the xen-kernel:

(XEN) /usr/src/xen-unstable.hg/xen/include/asm/mm.h:186:d0 Error pfn 100: 
rd=ffff8300df05c100, od=0000000000000000, caf=00000000, taf=0000000000000000
(XEN) mm.c:636:d0 Error getting mfn 100 (pfn 5555555555555555) from L1 entry 
8000000000100125 for dom32753
(XEN) /usr/src/xen-unstable.hg/xen/include/asm/mm.h:186:d0 Error pfn 100: 
rd=ffff8300df05c100, od=0000000000000000, caf=00000000, taf=0000000000000000
(XEN) mm.c:636:d0 Error getting mfn 100 (pfn 5555555555555555) from L1 entry 
8000000000100125 for dom32753

Xen does not crash, Dom0 continues to run.

System configuration:

x86_64 debug xen-kernel, x86_64 linux-2.6.18 dom0 kernel built from xen tree,
OpenSuSE 10.2 distribution as Dom0.

Steps to reproduce:

Launch yast, select "Network devices" and "Network card".
yast now reads config entries. If you are on a serial console where screen 
refreshes are slow enough, you should see that xen prints something.
Exit yast without changing anything. Back on command line run "xm dmesg".
There you can see the above xen messages.

This is repeatable. Doing this multiple times without reboot, you can always 
see the same message even with the same numbers.


Question:

Can anyone else on this list reproduce this?


Christoph


-- 
AMD Saxony, Dresden Germany
Operating System Research Center

Legal Information:
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vertretungsberechtigter Komplementär:
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Geschäftsführer der AMD Saxony LLC:
   Dr. Hans-R. Deppe, Thomas McCoy

Re: d0 Error pfn 100

[Keir Fraser]

This is a harmless message printed at loglevel XENLOG_INFO. Not much we can
do about it (apart from remove the message or reduce its loglevel further).
It is caused by yast doing some kind of scan of low memory, which we
disallow above physical address 1MB (there'll be nothing of interest at 1MB
or above anyway).

 -- Keir


On 24/5/07 13:21, "Christoph Egger" <Christoph.Egger@amd.com> wrote:

> 
> Hi!
> 
> I see these messages from the xen-kernel:
> 
> (XEN) /usr/src/xen-unstable.hg/xen/include/asm/mm.h:186:d0 Error pfn 100:
> rd=ffff8300df05c100, od=0000000000000000, caf=00000000, taf=0000000000000000
> (XEN) mm.c:636:d0 Error getting mfn 100 (pfn 5555555555555555) from L1 entry
> 8000000000100125 for dom32753
> (XEN) /usr/src/xen-unstable.hg/xen/include/asm/mm.h:186:d0 Error pfn 100:
> rd=ffff8300df05c100, od=0000000000000000, caf=00000000, taf=0000000000000000
> (XEN) mm.c:636:d0 Error getting mfn 100 (pfn 5555555555555555) from L1 entry
> 8000000000100125 for dom32753
> 
> Xen does not crash, Dom0 continues to run.
> 
> System configuration:
> 
> x86_64 debug xen-kernel, x86_64 linux-2.6.18 dom0 kernel built from xen tree,
> OpenSuSE 10.2 distribution as Dom0.
> 
> Steps to reproduce:
> 
> Launch yast, select "Network devices" and "Network card".
> yast now reads config entries. If you are on a serial console where screen
> refreshes are slow enough, you should see that xen prints something.
> Exit yast without changing anything. Back on command line run "xm dmesg".
> There you can see the above xen messages.
> 
> This is repeatable. Doing this multiple times without reboot, you can always
> see the same message even with the same numbers.
> 
> 
> Question:
> 
> Can anyone else on this list reproduce this?
> 
> 
> Christoph
> 

Re: d0 Error pfn 100

[Christoph Egger]

On Thursday 24 May 2007 14:28:33 Keir Fraser wrote:
> This is a harmless message printed at loglevel XENLOG_INFO. Not much we can
> do about it (apart from remove the message or reduce its loglevel further).
> It is caused by yast doing some kind of scan of low memory, which we
> disallow above physical address 1MB (there'll be nothing of interest at 1MB
> or above anyway).
>

Thanks for clarifing this. I will ignore this.

Christoph

-- 
AMD Saxony, Dresden Germany
Operating System Research Center

Legal Information:
AMD Saxony Limited Liability Company & Co. KG
Sitz (Geschäftsanschrift):
   Wilschdorfer Landstr. 101, 01109 Dresden, Deutschland
Registergericht Dresden: HRA 4896
vertretungsberechtigter Komplementär:
   AMD Saxony LLC (Sitz Wilmington, Delaware, USA)
Geschäftsführer der AMD Saxony LLC:
   Dr. Hans-R. Deppe, Thomas McCoy