Re: [Xen-devel] Hyp compat_memory_op() and 256 GB PV

[Keir Fraser <keir.fraser@xxxxxxxxxxxxx>]

On 18/02/2009 03:39, "Mukesh Rathor" <mukesh.rathor@xxxxxxxxxx> wrote:

> Moving on to 256 GB guest, the hyp is failing the XENMEM_populate_physmap
> hcall in compat_memory_op(). The problem is size too large for continuation
> encoding:
> 
>      /* Is size too large for us to encode a continuation? */
>      if ( cmp.rsrv.nr_extents > (UINT_MAX >> MEMOP_EXTENT_SHIFT))
>          return start_extent;
> 
>       for 256 GB : nr_extents == 0x4000000
> 
>   Currently at a loss on this one!

Well, who's making the compat call? Not the guest itself presumably since it
is 64-bit? So it's probably dom0? But I would think that dom0 would only do
large amounts of allocation for the new domU in xc_hvm_build.c, and that is
careful to allocate memory in batches of 8MB at a time.

Basically you need to track down the call site of the failed
compat_memory_op().

 -- Keir



_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel