Comment 2 for bug 1894942

Hi,
the patches LGTM and I'll make it part of the Ubuntu builds.

One question thou: on one hand "occasionally end up with" sounds like this is almost impossible to explicitly test, but then the attached debug patch suggests there might be a way to trigger this through protvirt.
But even if that is the case backporting it to all kind of older versions there is no protvirt.
So I wanted to ask:
a) is there any way to reliably trigger this for A/B testing of the fix as far back as qemu 2.5?
b) how real is the danger to hit and consequences of this in the pre-protvirt (=<Focal) era?