[Qemu-devel] Re: [COMMIT 733318e] don't call cpu_sychronize_state from reset handlers

[Jan Kiszka]

Glauber Costa wrote:
> On Fri, Sep 11, 2009 at 01:15:49PM +0200, Jan Kiszka wrote:
>> Anthony Liguori wrote:
>>> From: Glauber Costa <address@hidden>
>>>
>>> Doing this will make the vcpu ioctl be issued from the I/O thread, instead
>>> of cpu thread. The correct behaviour is to call it from within the cpu 
>>> thread,
>>> as soon as we are ready to go.
>> Note that in the good old days, this used to work properly (in qemu-kvm)
>> as registers write-back was routed through on_vcpu.
> 
> I believe we should avoid the use of those things, specially at 
> initialization. They are
> totally racy and fragile. One way to do that, is to do all the reset 
> functions inside the
> cpu thread.

As all this used to work fine in practice in upstream as well as in
qemu-kvm, I'm slightly unhappy about the current situation.

> 
> I already have something hacked up for this, will send as soon as I finish 
> testing.

OK, looking forward.

BTW, what's the state of the fix for the guest-debug regression under KVM?

Jan

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