I can reproduce the hang, except with a slightly different options. I
have spotted the places where the watchdog is set up incorrectly. I shall
post fixes shortly, once I have got them polished and tested. Feel free
to throw them at your qemu.
Also it's worth noting there's more breakage of the NMI watchdog for this
configuration ("maxcpus=1 noapic") -- it fails to tick on the CPU #0 on my
system for some reason, but that's well beyond the scope of this series,
so I am not going to look into it.
Maciej
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