On 2011-02-17 18:55, Marcelo Tosatti wrote:
>>>> @@ -1375,10 +1413,25 @@ static int kvm_put_vcpu_events(CPUState *env, int level)
>>>> return 0;
>>>> }
>>>>
>>>> - events.exception.injected = (env->exception_injected >= 0);
>>>> - events.exception.nr = env->exception_injected;
>>>> - events.exception.has_error_code = env->has_error_code;
>>>> - events.exception.error_code = env->error_code;
>>>> + if (env->interrupt_request & CPU_INTERRUPT_MCE) {
>>>> + /* We must not raise CPU_INTERRUPT_MCE if it's not supported. */
>>>> + assert(env->mcg_cap);
>>>> +
>>>> + env->interrupt_request &= ~CPU_INTERRUPT_MCE;
>>>> + if (env->exception_injected == EXCP08_DBLE) {
>>>> + /* this means triple fault */
>>>> + qemu_system_reset_request();
>>>> + env->exit_request = 1;
>>>> + }
>>>> + events.exception.injected = 1;
>>>> + events.exception.nr = EXCP12_MCHK;
>>>> + events.exception.has_error_code = 0;
>>>> + } else {
>>>> + events.exception.injected = (env->exception_injected >= 0);
>>>> + events.exception.nr = env->exception_injected;
>>>> + events.exception.has_error_code = env->has_error_code;
>>>> + events.exception.error_code = env->error_code;
>>>> + }
>>>
>>> IMO it is important to maintain a scope for kvm_put_vcpu_events /
>>> kvm_get_vcpu_events: they synchronize state to/from the kernel. Not more
>>> than that. Whatever you're trying to do here should be higher in the
>>> vcpu loop code.
>>
>> We pick up CPU_INTERRUPT_MCE and translate it into the right exception
>> that put_vcpu_events is about to sync to the kernel. What should be done
>> earlier of those steps? Calculating env->exception_injected?
>
> Everything but writeback. Update env->exception_injected/nr in
> process_irqchip_events, or in a separate kvm_arch_update_exceptions.
>
OK, will rework this.
>>>> return ret;
>>>> @@ -1678,10 +1736,17 @@ void kvm_arch_post_run(CPUState *env, struct kvm_run *run)
>>>> int kvm_arch_process_irqchip_events(CPUState *env)
>>>> {
>>>> if (kvm_irqchip_in_kernel()) {
>>>> + if (env->interrupt_request & CPU_INTERRUPT_MCE) {
>>>> + kvm_cpu_synchronize_state(env);
>>>> + if (env->mp_state == KVM_MP_STATE_HALTED) {
>>>> + env->mp_state = KVM_MP_STATE_RUNNABLE;
>>>> + }
>>>> + }
>>>
>>> Should not manipulate mp_state of a running vcpu (should only do that
>>> for migration when vcpu is stopped), since its managed by the kernel,
>>> for irqchip case.
>>
>> Not for asynchronously injected MCEs. The target CPU would simply
>> oversleep them. MCEs are not in the scope of the in-kernel irqchip.
>
> Pending MCE exception could break out of in-kernel halt emulation.
Can't follow. What do you mean? That the kernel already takes care? I
didn't find a trace, so I added that code.
Jan
--
Siemens AG, Corporate Technology, CT T DE IT 1
Corporate Competence Center Embedded Linux
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