Some versions of Windows hang on reboot if their TSC value is greater
than 2^54. The calibration of the Hyper-V reference time overflows
and fails; as a result the processors' clock sources are out of sync.
The issue is that the TSC _should_ be reset to 0 on CPU reset and
QEMU tries to do that. However, KVM special cases writing 0 to the
TSC and thinks that QEMU is trying to hot-plug a CPU, which is
correct the first time through but not later. Thwart this valiant
effort and reset the TSC to 1 instead, but only if the CPU has been
run once.
For this to work, env->tsc has to be moved to the part of CPUArchState
that is not zeroed at the beginning of x86_cpu_reset.
Reported-by: Vadim Rozenfeld <vrozenfe@redhat.com>
Supersedes: <20220324082346.72180-1-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
5286c36622