[Qemu-devel] Re: [PATCH] vnc: threaded server depends on io-thread

[Stefan Hajnoczi]

On Wed, Mar 9, 2011 at 10:57 AM, Corentin Chary
<address@hidden> wrote:
>>> The threaded VNC servers messed up with QEMU fd handlers without
>>> any kind of locking, and that can cause some nasty race conditions.
>>>
>>> The IO-Thread provides appropriate locking primitives to avoid that.
>>> This patch makes CONFIG_VNC_THREAD depends on CONFIG_IO_THREAD,
>>> and add lock and unlock calls around the two faulty calls.
>>
>> qemu-kvm currently doesn't compile with --enable-io-thread. is there an easy 
>> fix
>> for this?
>
> If IO Thread is not available, I'm afraid that --disable-vnc-thread is
> the only fix.
> Or, you can try to define some global mutex acting like iothread
> locks, but that doesn't sounds like an easy fix.

Jan or Marcelo can help here but qemu-kvm has an iothread equivalent
built in by default.  It should be possible to use that.

Stefan