2015-11-29 22:18:28

by Peter Crosthwaite

[permalink] [raw]
Subject: Adding VIRTIO to the multi_v7_defconfig

Hi,

I started a small project to test as many QEMU emulated ARM boards
using the multi_v7 defconfig:

https://lists.gnu.org/archive/html/qemu-devel/2015-10/msg00755.html

One thing that came up was we cannot use the virt board as it relies
on virtio hotplug and drivers to get block and network support. The
defconfig is missing the drivers. Should we add the VIRTIO drivers to
the defconfig to bring this into play?

Regards,
Peter


2015-11-29 22:32:26

by Arnd Bergmann

[permalink] [raw]
Subject: Re: Adding VIRTIO to the multi_v7_defconfig

On Sunday 29 November 2015 14:18:24 Peter Crosthwaite wrote:
>
> I started a small project to test as many QEMU emulated ARM boards
> using the multi_v7 defconfig:
>
> https://lists.gnu.org/archive/html/qemu-devel/2015-10/msg00755.html
>
> One thing that came up was we cannot use the virt board as it relies
> on virtio hotplug and drivers to get block and network support. The
> defconfig is missing the drivers. Should we add the VIRTIO drivers to
> the defconfig to bring this into play?

Yes, please send a patch, this is definitely useful. We normally ask
everyone to use loadable modules for newly enabled device drivers
in multi_v7_defconfig, but we might actually use built-in drivers
here if that would otherwise be the only module needed for booting.

Arnd

2015-11-29 22:56:59

by Peter Crosthwaite

[permalink] [raw]
Subject: Re: Adding VIRTIO to the multi_v7_defconfig

On Sun, Nov 29, 2015 at 2:31 PM, Arnd Bergmann <[email protected]> wrote:
> On Sunday 29 November 2015 14:18:24 Peter Crosthwaite wrote:
>>
>> I started a small project to test as many QEMU emulated ARM boards
>> using the multi_v7 defconfig:
>>
>> https://lists.gnu.org/archive/html/qemu-devel/2015-10/msg00755.html
>>
>> One thing that came up was we cannot use the virt board as it relies
>> on virtio hotplug and drivers to get block and network support. The
>> defconfig is missing the drivers. Should we add the VIRTIO drivers to
>> the defconfig to bring this into play?
>
> Yes, please send a patch, this is definitely useful. We normally ask
> everyone to use loadable modules for newly enabled device drivers
> in multi_v7_defconfig, but we might actually use built-in drivers
> here if that would otherwise be the only module needed for booting.
>

So minimally I am looking for:

CONFIG_VIRTIO_PCI=y"
CONFIG_VIRTIO_BLK=y"
CONFIG_VIRTIO_NET=y"

As that gets you booted with network without needing initrd. I guess
the rest of VIRTIO makes more sense as modules as follow up work?

Regards,
Peter

> Arnd

2015-11-29 23:15:54

by Arnd Bergmann

[permalink] [raw]
Subject: Re: Adding VIRTIO to the multi_v7_defconfig

On Sunday 29 November 2015 14:56:53 Peter Crosthwaite wrote:
>
> So minimally I am looking for:
>
> CONFIG_VIRTIO_PCI=y"
> CONFIG_VIRTIO_BLK=y"
> CONFIG_VIRTIO_NET=y"
>
> As that gets you booted with network without needing initrd. I guess
> the rest of VIRTIO makes more sense as modules as follow up work?

Sounds reasonable to me, though we could debate about VIRTIO_NET.
If nobody else objects, just make it built-in.

Arnd