Re: [Qemu-devel] [PATCHv2] Fix virtio-console failure on unconnected pty

[Andreas Färber]

Am 29.12.2011 14:27, schrieb Amit Shah:
> On (Thu) 29 Dec 2011 [13:47:43], Christian Borntraeger wrote:
>> From: Christian Borntraeger <address@hidden>
>>     
>> when I tried qemu with -virtio-console pty the guest hangs and attaching on 
>> /dev/pts/<x> does
>> not return anything if the attachement is too late.

"attachment", while you're at it.

Andreas

>> Turns out that the console is already throttled and the guest is heavily 
>> spinning but get_buf
>> never returns the buffer. There seems to be no way for the console to 
>> unthrottle the port.
> 
> It doesn't really get throttled, since the throttling
> enabling/disabling isn't yet done in QEMU.  What happens is that the
> chardev buffer gets filled up and qemu_chr_fe_write() doesn't return
> -- send_all() keeps spinning.
> 
> I'll adjust the commit log message and submit.
> 
> Thanks.
> 
>               Amit

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