please enable CONFIG_VIRTIO_MMIO on armmp

[Riku Voipio]

[Impact]
Degraded performance during network and disk activity in a kvm guest.

[Test case]
Try booting a vm and do some disk/net activity with and without this driver.

[Regression potential]
In case of regressions, it will just hit people using kvm on 32bit armhf hardware (the lpae variant in particular): we already had this driver on in the past, it's on by default on every arch, it's widely used and upstream is very active - i say it's a low potential regression.

--
Hi,

The current armmp (linux-image-3.16.0-26-generic_3.16.0-26.34_armhf.deb) could have virtio-mmio enabled for faster vm guests. Currenlty it seems to have:

CONFIG_NET_9P_VIRTIO=m
CONFIG_VIRTIO_BLK=y
CONFIG_SCSI_VIRTIO=m
CONFIG_VIRTIO_NET=y
CONFIG_CAIF_VIRTIO=m
CONFIG_VIRTIO_CONSOLE=y
CONFIG_HW_RANDOM_VIRTIO=m
CONFIG_VIRTIO=y
CONFIG_VIRTIO_PCI=y
# CONFIG_VIRTIO_BALLOON is not set
# CONFIG_VIRTIO_MMIO is not set

Now using virtio net and block is not possible, and you have to revert to emulated devices.

[Brad Figg (brad-figg)]

This bug is missing log files that will aid in diagnosing the problem. From a terminal window please run:

apport-collect 1396470

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.

[Paolo Pisati (p-pisati)]

can you try one of these kernels and report if it solves the problem for you?

http://people.canonical.com/~ppisati/lp1396470/

thanks!

[Riku Voipio (riku-voipio)]

Hi Paolo,

Thanks for quick update.

previous boot time (with SD emulation): Up 113.00 seconds.
with your kernel and virtio disk:Up 78.19 seconds.

So yes, works perfectly!

On 2 December 2014 at 13:08, Paolo Pisati <email address hidden> wrote:
> can you try one of these kernels and report if it solves the problem for
> you?
>
> http://people.canonical.com/~ppisati/lp1396470/
>
> thanks!
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1396470
>
> Title:
> please enable CONFIG_VIRTIO_MMIO on armmp
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1396470/+subscriptions

[Leann Ogasawara (leannogasawara)]

Fix Committed for both Utopic and Vivid. I accidentally added a Lucid task so have marked that Invalid. Thanks.

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux - 3.18.0-8.9

---------------
linux (3.18.0-8.9) vivid; urgency=low

  [ Leann Ogasawara ]

  * Release Tracking Bug
    - LP: #1407692
  * rebase to v3.18.1
  * ubuntu: AUFS -- Resolve build failure union has no member named
    'd_child'

  [ Upstream Kernel Changes ]

  * arm64: optimized copy_to_user and copy_from_user assembly code
    - LP: #1400349
  * x86, kvm: Clear paravirt_enabled on KVM guests for espfix32's benefit
    - LP: #1400314
    - CVE-2014-8134
  * rebase to v3.18.1
 -- Leann Ogasawara <email address hidden> Mon, 05 Jan 2015 09:12:32 -0800