[Pkg-xen-devel] Bug#658606: Bug#658606: Xen 4.0 dom0 boot hangs "Waiting for /dev to be populated"

[Ian Campbell]

On Tue, 2012-02-14 at 16:23 +0000, Owen Dunn wrote:
> On Tue, 14 Feb 2012, Ian Campbell wrote:
> 
> > On Tue, 2012-02-14 at 12:19 +0000, Owen Dunn wrote:
> >> On Tue, 14 Feb 2012, Ian Campbell wrote:
> >>
> >>> This could be a dom0 interrupt handling problem of some sort. You don't
> >>> say which dom0 kernel version you are using but please could you try the
> >>> latest one from Squeeze (2.6.32-41) -- there were some IRQ related fixes
> >>> in the -39/-40 timeframe.
> >>
> >> The dom0 kernel I'm using is linux-image-2.6.32-5-xen-amd64 version
> >> 2.6.32-41
> >
> > OK, thanks.
> >
> > Could you try booting with the debug options described at
> > http://wiki.xen.org/wiki/XenParavirtOps#Maybe_it_is_something_obvious.3F_How_do_I_make_the_bootup_more_verbose.3F
> > Perhaps that will tell us something. Using a Serial console to capture
> > the full logs would also be very useful if you have the equipment
> > available.
> 
> Right.  I tried this twice.  The first time I (accidentally) omitted the 
> debug options on the kernel command line but included them on the xen 
> command line, so:
> 
> multiboot /boot/xen-4.0-amd64.gz placeholder  loglvl=all guest_loglvl=all com1=115200,8n1 console=com1
> 
> ...in the grub2 config.
> 
> The boot proceeded as I've become used to and I had to poke shift on the 
> system's USB keyboard several times to help it along the way.  I've 
> attached the result from this boot as xenser.log.
> 
> The second time I added the debug options to the kernel command line as 
> well, so I had:
> 
> module /boot/vmlinuz-2.6.32-5-xen-amd64 placeholder root=UUID=c392e16b-5f39-42ed-94cb-15127e01a082 ro earlyprintk=xen debug loglevel=8
> 
> ...in the grub2 config.
> 
> This time the boot went extremely fast, didn't pause at the udevadm settle 
> point, and was extremely responsive once it had come up fully!  The debug 
> log from this is attached as xenknlser.log

Unfortunately there's a big chunk missing from the middle of the log.
Might be a serial overrun but it looks quite long.

I suppose it might be worth adding the options one at a time to see
which one fixed the issue for you? None of them look like they should
cause anything to get fixed to me...

> > Also would it be possible to try the 4.1 hypervisor from Wheezy on this
> > machine?
> 
> Probably...  What packages do I need to install to do that?

Just xen-hypervisor-4.1-amd64 since we don't really care about tools etc
at this stage.

You could even just extract the xen.gz from that package and drop it
in /boot for the purposes of this test, if you want to avoid polluting
your Squeeze system with partial upgrades.

Ian.

-- 
Ian Campbell

Beauty and harmony are as necessary to you as the very breath of life.