Bug: xm restore in unstable/FC4

[Michael Paesold]

I have tried to do save/restore on FC 4. xm save now works (in the
latest development version, where the migrate/ directory is correctly
created by the RPM).

xm restore does not work, it fails in xc_linux_restore calling
xm_domain_create. Error message in xfrd log is "Could not create
domain. pfns=65536, 262144KB".

Debugging xfrd with gdb gave further information:

Inside xm_domain_create no error occurs at all. The result from the
do_dom_mem_op(xc_handle, MEMOP_increase_reservation,...) call is the
expected value of 65536 (mem_kb/4).
This is stored into the variable err, which is then returned.

Back in xc_linux_restore, the code now thinks that a result different then 0
is an error, when in fact -1 would indicate an error:

This seems to be wrong:
    /* Create domain on CPU -1 so that it may auto load-balance in future.
*/
    if ( xc_domain_create(xc_handle, nr_pfns * (PAGE_SIZE / 1024),
                          -1, 1, &dom) )
    {
        xcio_error(ioctxt, "Could not create domain. pfns=%d, %dKB",
                   nr_pfns,nr_pfns * (PAGE_SIZE / 1024));
        goto out;
    }

This should be probably be changed to xc_domain_create(..) == -1 as
condition for an error.

Well, I have just looked into the sources in the BitKeeper repository and
saw that this code has already changed substantially for some weeks now. Now
I don't really understand, what the FC4 package is really built from.

It says xen-2-20050530 -- xen 2 -- but booting xen says 3.0 devel.
Rik, could you clear this up for me, please? Thanks.

Best Regards,
Michael Paesold