Re: [patch] xen udev rule interfering with openvpn

[Teck Choon Giam <giamteckchoon@gmail.com>]

On Mon, May 21, 2012 at 8:31 PM, Ian Campbell <Ian.Campbell@citrix.com> wrote:
> On Sun, 2012-05-13 at 01:39 +0100, Teck Choon Giam wrote:
>> On Sun, May 13, 2012 at 7:37 AM, Teck Choon Giam
>> <giamteckchoon@gmail.com> wrote:
>> > On Sun, May 13, 2012 at 6:30 AM, Ian Campbell <Ian.Campbell@citrix.com> wrote:
>> >> On Sat, 2012-05-12 at 23:00 +0100, Teck Choon Giam wrote:
>> >>> On Sat, May 12, 2012 at 3:29 PM, Teck Choon Giam
>> >>> <giamteckchoon@gmail.com> wrote:
>> >>> > On Sat, May 12, 2012 at 7:53 AM, Teck Choon Giam
>> >>> > <giamteckchoon@gmail.com> wrote:
>> >>> >> On Fri, May 11, 2012 at 10:53 PM, Ian Jackson <Ian.Jackson@eu.citrix.com> wrote:
>> >>> >>> Ian Campbell writes ("Re: [Xen-devel] [patch] xen udev rule interfering with openvpn"):
>> >>> >>>> libxl/xend: name tap devices vifX.Y-emu
>> >>> >>>
>> >>> >>> Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
>> >>> >>
>> >>> >> This is my backport version which excludes the following:
>> >>> >>
>> >>> >> Lastly also move libxl__device_* to a better place in the header, otherwise the
>> >>> >> comment about evgen stuff isn't next to the associated functions (noticed jsut
>> >>> >> because I was going to add nic_devname near to the setdefault functions)
>> >>> >>
>> >>> >> I have tested with xm and xl with and without vifname set in domU
>> >>> >> config for hvmdomain and pvdomain.
>> >>> >
>> >>> > Sorry, when re-test one of the test case failed... xm create hvmdomain
>> >>> > with vifname set.  I must have missed certain test case :(
>> >>>
>> >>> The same test case failed for xen unstable latest changeset 25326:cd4dd23a831d.
>> >>
>> >> Oh dear.
>> >>
>> >>> My tests as below:
>> >>
>> >> Which ones fail?
>> >>
>> >>> 1. xm create pvdomain without vifname set
>> >>> 2. xl create pvdomain without vifname set
>> >>> 3. xm create hvmdomain without vifname set
>> >>> 4. xl create hvmdomain without vifname set
>> >>> 5. xm create pvdomain with vifname set
>> >>> 6. xl create pvdomain with vifname set
>> >>> 7. xm create hvmdomain with vifname set
>> >
>> > xm create hvmdomain with vifname set
>> >
>> >
>> > I track down the problem already.  It happens that xm and xl behave
>> > differently when creating $dev device?
>> >
>> > In short, just set $dev down before:
>> > do_or_die ip link set "$dev" name "$vifname"
>> > Then set $vifname up after the above fix my problem.
>> >
>> > Is the above suitable in upstream/unstable?  If yes, can you fix that
>> > in xen-unstable or you need me to submit a patch for review for
>> > xen-unstable?
>> >
>> > With the below partial of my latest backport patch fix the problem but
>> > I have to re-run all tests to double confirm all are fix and good to
>> > go :p
>>
>> Attached is my final backport for xen-4.1-testing which passed all my
>> tests as stated below:
>>
>> 1. xm create pvdomain without vifname set
>> 2. xl create pvdomain without vifname set
>> 3. xm create hvmdomain without vifname set
>> 4. xl create hvmdomain without vifname set
>> 5. xm create pvdomain with vifname set
>> 6. xl create pvdomain with vifname set
>> 7. xm create hvmdomain with vifname set
>> 8. xl create hvmdomain with vifname set
>>
>> My initial backport patch failed for test no. 7 and when I perform
>> test for all the above in latest xen-unstable it failed in test no. 7
>> as well.
>
> OK, can we concentrate on the xen-unstable failure first, hopefully
> addressing that will naturally fix 4.1 too but I don't wan't to get
> confused between the two.

Sure.  My previous mail is actually asking what to do with #7 in
xen-unstable not in xen-4.1-testing.

>
> How does case #7 fail? Do you get both devices created but not placed on
> the bridge or something else?

I am not sure just in #7 fail to create.  The error as below:

# xm create hvmdomaintest-vifname.cfg
Using config file "./hvmdomaintest-vifname.cfg".
Error: Device 0 (vif) could not be connected. ip link set vif1.0-emu
name b1-emu failed


>
> What names do the devices end up with? ("ifconfig -a", while guest is
> running, "brctl show" also useful)

Can't even create the hvmdomain with vifname set.  If you mean trying
to capture the ifconfig -a output while xm create hvmdomain with
vifname set... the interval for xm create hvmdomain with vifname set
is too short for me to issue ifconfig -a and brctl show output in
another terminal :(

> What is the qemu command line? (from ps, while guest is running)

Not relevant since can't create the hvmdomain with vifname set.

>
> What is the name in xenstore? ("xenstore-ls -fp", again while guest is
> running)

Not relevant since can't create the hvmdomain with vifname set.

>
> Thanks, sorry for the delay in responding to this one.

It is fine and I totally understand developers are busy and mostly
miss certain posts or threads or emails.

Just to confirm... are we going to "throw away" xm in 4.2 and use only xl?

Thanks.

Kindest regards,
Giam Teck Choon


>
> Ian.
>