Re: [Qemu-devel] [PATCH v5 2/2] mach-virt: Provide sample configuration files

[Laszlo Ersek]

On 02/08/17 20:36, Peter Maydell wrote:
> On 8 February 2017 at 19:28, Andrea Bolognani <address@hidden> wrote:
>> On Wed, 2017-02-08 at 18:32 +0000, Peter Maydell wrote:

>>> Won't most guests expect serial to be the default
>>> PL011 UART ?
>>
>> Possibly. I'm using virtconsole here (and in q35*serial.cfg)
>> mostly to have as much VirtIO as possible, but I also
>> document the fact that you might want or need to use the
>> native serial console instead.
>>
>> Moreover, something that I haven't been able to do on
>> mach-virt (even though I could on q35, but again, I want the
>> files to be as close as possible) is to configure the serial
>> console from the configuration file.
> 
> If there's stuff we can fix in the virt board to make
> this work the way it does on the PC model I'm happy
> to make fixes to help.
> 
>> Seeing as we have an alternative, I'd rather keep it this
>> way and minimize the number of command line arguments the
>> user needs to specify.
> 
> The trouble with using virtconsole is that you have to
> get quite a long way forward (probing and setting up
> PCI, etc) before you can get any kind of console output.
> "System doesn't boot and doesn't produce any output"
> is a common and really annoying failure mode in the
> ARM world, and I think that using virtconsole is
> asking for that kind of thing to happen more rather
> than less often.

My point exactly.
Thanks
Laszlo

> (Plus having two different serial
> ports in the guest means that now the user has to
> configure where both of them are supposed to output.)
> 
> thanks
> -- PMM
>