libvirt users - Feb 2014 - Re: Problems with qemu-system-arm and isa-serial

Hi,

I'm trying to use libvirt for an armel virtual machine hosted 
into an x86_64 box.

I know the command line to start qemu-system-arm directly, but I 
cannot figure a proper .xml configuration file to let libvirt do 
this job.

The main problem is that I want a serial console attached via 
telnet, this is the Qemu incantation:

-serial telnet::4000,server,nowait,nodelay

Wahtever I do in libvirt, I get this paramter added:

-device isa-serial

which causes Qemu to fail:

qemu-system-arm -M versatileab -device isa-serial \
    -kernel vmlinuz-2.6.32-5-versatile
qemu-system-arm: -device isa-serial: No 'ISA' bus found for device
'isa-serial'

How can I instead have -device pl011, or just have the default 
devices provided by qemu-system-arm, i.e. to prevent libvirt from 
adding the -nodefaults switch?

Thank you!

-- 
Niccolo Rigacci - http://www.rigacci.net/
Campi Bisenzio - Firenze - Italy
Tel. Office: +39-055-9331021, Mobile: +39-327-5619352

On Mon, Feb 17, 2014 at 05:01:05PM +0100, Niccolo Rigacci
wrote:
> Hi,
>
> I'm trying to use libvirt for an armel virtual machine hosted
> into an x86_64 box.
>
> I know the command line to start qemu-system-arm directly, but I
> cannot figure a proper .xml configuration file to let libvirt do
> this job.
>
We're still missing a full support for qemu-system-arm because it has
different options, works differently and so on.
> The main problem is that I want a serial console attached via
> telnet, this is the Qemu incantation:
>
> -serial telnet::4000,server,nowait,nodelay
>
this is an old-style for -chardev serial, I believe
> Wahtever I do in libvirt, I get this paramter added:
>
> -device isa-serial
>
and this is new-style for x86 qemu, however, arm-based qemu haven't
adopted this option yet.
> which causes Qemu to fail:
>
> qemu-system-arm -M versatileab -device isa-serial \
>     -kernel vmlinuz-2.6.32-5-versatile
> qemu-system-arm: -device isa-serial: No 'ISA' bus found for device
'isa-serial'
>
> How can I instead have -device pl011, or just have the default
> devices provided by qemu-system-arm, i.e. to prevent libvirt from
> adding the -nodefaults switch?
>
libvirt adds -nodefault and similar options (and has to add them)
because otherwise there are devices which libvirt doesn't know of and
is thus unable to work properly.  I found one small thing in the code
which might help you, I'll cook-up a patch and will put you in Cc
when sending, can you try compiling it with that patch added (or from
git when pushed) to see whether that will help you?

Have a nice day,
Martin
> Thank you!
>
> --
> Niccolo Rigacci - http://www.rigacci.net/
> Campi Bisenzio - Firenze - Italy
> Tel. Office: +39-055-9331021, Mobile: +39-327-5619352
>
> _______________________________________________
> libvirt-users mailing list
> libvirt-users@redhat.com
> https://www.redhat.com/mailman/listinfo/libvirt-users

On Tue, Feb 18, 2014 at 09:10:58AM +0100, Martin Kletzander
wrote:
> On Mon, Feb 17, 2014 at 05:01:05PM +0100, Niccolo Rigacci wrote:
> > Hi,
> >
> > I'm trying to use libvirt for an armel virtual machine hosted
> > into an x86_64 box.
> >
> > I know the command line to start qemu-system-arm directly, but I
> > cannot figure a proper .xml configuration file to let libvirt do
> > this job.
> >
>
> We're still missing a full support for qemu-system-arm because it has
> different options, works differently and so on.
>
> > The main problem is that I want a serial console attached via
> > telnet, this is the Qemu incantation:
> >
> > -serial telnet::4000,server,nowait,nodelay
> >
>
> this is an old-style for -chardev serial, I believe
>
> > Wahtever I do in libvirt, I get this paramter added:
> >
> > -device isa-serial
> >
>
> and this is new-style for x86 qemu, however, arm-based qemu haven't
> adopted this option yet.
>
To be a bit more precise, only *some* machine types support this
option, others may have adopted it, but don't use it properly and what
you describe is most probably properly adopted option, but qemu not
adding an ISA controller (apart from non-arm qemu which has it
always).  Can you send me the output of 'virsh capabilities' and
'virsh dumpxml <domain_name>' so I can have a look at what's
the
particular type of machine you are using for which we should not use
'-device isa-serial'?

Thanks,
Martin
> > which causes Qemu to fail:
> >
> > qemu-system-arm -M versatileab -device isa-serial \
> >     -kernel vmlinuz-2.6.32-5-versatile
> > qemu-system-arm: -device isa-serial: No 'ISA' bus found for
device 'isa-serial'
> >
> > How can I instead have -device pl011, or just have the default
> > devices provided by qemu-system-arm, i.e. to prevent libvirt from
> > adding the -nodefaults switch?
> >
>
> libvirt adds -nodefault and similar options (and has to add them)
> because otherwise there are devices which libvirt doesn't know of and
> is thus unable to work properly.  I found one small thing in the code
> which might help you, I'll cook-up a patch and will put you in Cc
> when sending, can you try compiling it with that patch added (or from
> git when pushed) to see whether that will help you?
>
> Have a nice day,
> Martin
>
> > Thank you!
> >
> > --
> > Niccolo Rigacci - http://www.rigacci.net/
> > Campi Bisenzio - Firenze - Italy
> > Tel. Office: +39-055-9331021, Mobile: +39-327-5619352
> >
> > _______________________________________________
> > libvirt-users mailing list
> > libvirt-users@redhat.com
> > https://www.redhat.com/mailman/listinfo/libvirt-users

> _______________________________________________
> libvirt-users mailing list
> libvirt-users@redhat.com
> https://www.redhat.com/mailman/listinfo/libvirt-users