Il 17/07/2014 15:25, Marcin Gibuła ha scritto:
+static void do_kvm_cpu_synchronize_state_always(void *arg)
+{
+ CPUState *cpu = arg;
+
+ kvm_arch_get_registers(cpu);
+}
+
The name of the hack^Wfunction is tricky, because compared to
do_kvm_cpu_synchronize_state there are three things you change:
1) you always synchronize the state
2) the next call to do_kvm_cpu_synchronize_state will do
kvm_arch_get_registers
3) the next CPU entry will call kvm_arch_put_registers:
if (cpu->kvm_vcpu_dirty) {
kvm_arch_put_registers(cpu, KVM_PUT_RUNTIME_STATE);
cpu->kvm_vcpu_dirty = false;
}
It is easy to find out if the "fix" is related to 1 or 2/3: just write
if (cpu->kvm_vcpu_dirty) {
printf ("do_kvm_cpu_synchronize_state_always: look at 2/3\n");
kvm_arch_get_registers(cpu);
} else {
printf ("do_kvm_cpu_synchronize_state_always: look at 1\n");
}
To further refine between 2 and 3, I suppose you can set a breakpoint on
cpu_synchronize_all_states and kvm_cpu_exec, and see which is called
first after cpu_synchronize_all_states_always.
I still lean very much towards reverting the patches now. We can
reapply them, fixed, in 2.1.1.
Paolo
