unstable grant table issues?

unstable grant table issues?

[Gerd Knorr]

  Hi,

current unstable (hg22ccddf93c40c7962109d1763d88b9f65af1f680)
fails to boot DomU for me (32-bit, unpatched).  Seems to be a
problem with the grant tables.

Last DomU messages:

  VFS: Mounted root (ext2 filesystem) readonly.
  Freeing unused kernel memory: 168k freed
  attempt to access beyond end of device
  sda1: rw=0, want=1717986920, limit=8388608

The domain is still in the "xm list" after that and can't be
killed by "xm destroy".

In the xen message log I see this (xen built with debug=y):

  [ ... ]
  (XEN) Scrubbing Free RAM: ...........done.
  (XEN) *** Serial input -> DOM0 (type 'CTRL-a' three times to switch input to Xen).
  (XEN) (file=/work/bk/xen/test-build-i686-22ccddf93c40c7962109d1763d88b9f65af1f680/xen/include/asm/mm.h, line=187) Error pfn 100: rd=ff19d080, od=00000000, caf=00000000, taf=00000000
  (XEN) (file=/work/bk/xen/test-build-i686-22ccddf93c40c7962109d1763d88b9f65af1f680/xen/include/asm/mm.h, line=187) Error pfn 100: rd=ff19d080, od=00000000, caf=00000000, taf=00000000
  (XEN) (file=/work/bk/xen/test-build-i686-22ccddf93c40c7962109d1763d88b9f65af1f680/xen/include/asm/mm.h, line=187) Error pfn 100: rd=ff19d080, od=00000000, caf=00000000, taf=00000000
  (XEN) (file=grant_table.c, line=500) Bad handle (0).
  (XEN) (file=grant_table.c, line=500) Bad handle (8192).
  (XEN) (file=grant_table.c, line=500) Bad handle (40264).
  (XEN) (file=grant_table.c, line=500) Bad handle (0).
  (XEN) (file=grant_table.c, line=500) Bad handle (20480).
  (XEN) (file=grant_table.c, line=500) Bad handle (0).

The error messages from mm.h appeared during Dom0 bootup, but seem to be
harmless.  The grant_table.c messages where triggered by the attempt to boot
DomU.

Config file looks like this:

  master-xen root ~# cat /vm/sl93/config.xen3
  # general
  kernel = "/vm/sl93/vmlinuz3";
  memory = 128;
  name = "sl93";
  builder = "linux";

  # disk
  #disk = [ 'file:/dev/xen/sl93,sda1,w' ];
  disk = [ 'phy:xen/sl93,sda1,w' ];
  root = "/dev/sda1 ro";

  # network
  vif = [ 'mac=aa:00:78:65:6e:31, bridge=eth0' ];
  dhcp = "dhcp";

Which of the two "disk = " lines I use doesn't make a difference (Is there any
btw.?).

Any idea?

  Gerd

Re: unstable grant table issues?

[Keir Fraser]

On 4 Jul 2005, at 15:49, Gerd Knorr wrote:

> current unstable (hg22ccddf93c40c7962109d1763d88b9f65af1f680)
> fails to boot DomU for me (32-bit, unpatched).  Seems to be a
> problem with the grant tables.

Yep. I'm just testing a fix right now. Should be pushed in a few 
minutes...

  -- Keir

Re: unstable grant table issues?

[Gerd Knorr]

  Hi,

> >fails to boot DomU for me (32-bit, unpatched).  Seems to be a
> >problem with the grant tables.
> 
> Yep. I'm just testing a fix right now. Should be pushed in a few 
> minutes...

Works again, thanks.

These lines are still there tough:

  (XEN) (file=[...]/mm.h, line=187) Error pfn 100: rd=ff19d080, od=00000000, caf=00000000, taf=00000000

Any idea what this is?

  Gerd

-- 
panic("it works"); /* avoid being flooded with debug messages */

Re: unstable grant table issues?

[Keir Fraser]

On 5 Jul 2005, at 10:19, Gerd Knorr wrote:

> Works again, thanks.
>
> These lines are still there tough:
>
>   (XEN) (file=[...]/mm.h, line=187) Error pfn 100: rd=ff19d080, 
> od=00000000, caf=00000000, taf=00000000
>
> Any idea what this is?

Something is trying to map the page at 1MB -- probably some user-space 
table-scanning program (for example, I know some versions of dmidecode 
run past the 1MB boundary).

Actually, if your machine is non-ACPI then it is probably the kernel's 
ACPI code. That has had a bug for ages where it ought to scan 
0xE0000-0xFFFFF, but actually scans 1MB from 0xE0000. That would get 
you the error you're seeing. :-) I submitted a patch once...

  -- Keir