[Acked] [PATCH] [S/master-next] [SRU] armhf: virtio_mmio support

[Andy Whitcroft]

On Fri, Oct 04, 2013 at 04:25:20PM +0200, Paolo Pisati wrote:
> BugLink: http://bugs.launchpad.net/bugs/1235277
> 
> SRU Justification:
> 
> Impact: qemu 1.6 adds support for virtio memory mapped devices (like net and
> block) on arm. While S will probably ship with qemu 1.5, we know it'll be
> provided in a ppa and we want to take advantage of the speedup offered by
> virtio, so
> 
> 1) turn on virtio_mmio on armhf (generic and generic-lpae)
> 2) uniform VIRTIO* support among all the different archs, making it a
> compiled-in options like on i386 and amd64
> 
> Fix: apply the attached config patch and recompile a kernel with it
> 
> Testcase: try booting a qemu kvm using a kernel without this patch:
> 
> sudo qemu-system-arm -machine vexpress-a15 -cpu cortex-a15 -enable-kvm -m 512M
> -kernel /boot/vmlinuz-`uname -r` -append 
> "console=ttyAMA0 earlyprintk=serial root=/dev/mmcblk0 ro rootfstype=ext4"
> -serial stdio -dtb /lib/firmware/`uname -r`/device-tree/vexpress-v2p-ca15-tc1.dtb
> -initrd /boot/initrd.img-`uname -r`
> -drive if=sd,cache=writeback,file=saucy-server-cloudimg-armhf.img -net nic
> -net user,hostfwd=tcp::2223-:22 -display none
> 
> and then try to boot another instance using a kernel with the config patch
> applied:
> 
> sudo qemu-system-arm -machine vexpress-a15 -cpu cortex-a15 -enable-kvm -m 512M
> -kernel /boot/vmlinuz-`uname -r` -append
> "console=ttyAMA0 earlyprintk=serial root=/dev/vda ro rootfstype=ext4"
> -serial stdio -dtb /lib/firmware/`uname -r`/device-tree/vexpress-v2p-ca15-tc1.dtb
> -initrd /boot/initrd.img-`uname -r`
> -drive if=none,cache=writeback,file=saucy-server-cloudimg-armhf.img,id=foo
> -device virtio-blk-device,drive=foo -display none -netdev tap,id=tap0
> -device virtio-net-device,netdev=tap0
> 
> the difference is noticeable to the naked eye.
> 
> Paolo Pisati (1):
>   UBUNTU: [Config] arm: VIRTIO_[BLK|NET|MMIO]=y
> 
>  debian.master/abi/3.11.0-9.16/armhf/generic-lpae.modules | 5 -----
>  debian.master/config/amd64/config.common.amd64           | 4 ----
>  debian.master/config/armhf/config.common.armhf           | 1 +
>  debian.master/config/armhf/config.flavour.generic        | 5 -----
>  debian.master/config/armhf/config.flavour.generic-lpae   | 5 -----
>  debian.master/config/config.common.ubuntu                | 4 ++++
>  debian.master/config/i386/config.common.i386             | 4 ----
>  7 files changed, 5 insertions(+), 23 deletions(-)

Acked-by: Andy Whitcroft <apw at canonical.com>

-apw