[SeaBIOS] reboot fails with QEMU "isapc" machine type

[Kevin O'Connor]

On Mon, Feb 05, 2018 at 12:46:41PM +0000, Daniel P. Berrangé wrote:
> I was experimenting with old MS-DOS 6.22 under QEMU with the 'isapc' machine
> type, and found it is not able to reboot the guest. Bisecting QEMU blamed
> the QEMU change that rebased from "rel-1.9.3", to "rel-1.10.0". Further
> bisecting SeaBIOS blames this change:

What version of QEMU are you using?  I can't get anything to run with
the isapc machine type - I just get:

SeaBIOS (version rel-1.11.0-11-g4a6dbce-dirty-20180207_213141-morn.lan)
BUILD: gcc: (GCC) 7.2.1 20170915 (Red Hat 7.2.1-2) binutils: version 2.29-6.fc27
No Xen hypervisor found.
Unable to unlock ram - bridge not found

I didn't think isapc was functional at all.

-Kevin