Re: [Qemu-devel] [PATCH v5 2/3] pc & q35: Add new machine opt max-ram-below-4g

[Gerd Hoffmann]

  Hi,

> > IMO xen should use a versioned machine type to make live migration more
> > reliable.  IIRC this was discussed anyway for other reasons (see
> > xen-platform-pci discussions, picking pc-i440fx-1.6 IIRC).
> 
> That is happening as far as I know and does not directly impact this
> patch set.
> 
> >    That should
> > also make qemu use the memory layout expected by old xen.
> 
> Currently xen just ignores the memory layout that QEMU sets up
> and does it's own way.  So no, this does not make QEMU use the
> memory layout expected by old xen.

Why?  "-M pc-i440fx-1.6" will make qemu use the same memory layout it
used to have before gbalign support was added.  And that should match
what old xen versions are setting up ...

cheers,
  Gerd