Re: pvgrub2 legacy_configfile issues: /sbin/init exec error -8

[Andy Smith]

Hi Andrei,

On Sat, Feb 11, 2017 at 05:46:03PM +0300, Andrei Borzenkov wrote:
> What happens if you load the same kernel manually in dom0?

When I do:

sudo /usr/lib/xen-4.4/bin/pygrub -n /dev/myvg/debtest1_xvda

I get:

linux (kernel '<kernel:/boot/vmlinuz-3.16.0-4-amd64>')(ramdisk 
'<ramdisk:/boot/initrd.img-3.16.0-4-amd64>')(args 
'root=UUID=38420e46-6123-477d-ba23-baeba8ac0d59 ro')

(as mentioned, if I boot it with pygrub then it works)

Putting that directly in a Xen guest config file like:

$ sudo kpartx -va /dev/mapper/myvg-debtest1_xvda add map myvg-debtest1_xvda1 
(253:29): 0 10483712 linear /dev/mapper/myvg-debtest1_xvda 2048
$ sudo mount /dev/mapper/myvg-debtest1_xvda1 /mnt/xen
$ sudo cp /mnt/xen/boot/vmlinuz-3.16.0-4-amd64 /tmp/kernel
$ sudo cp /mnt/xen/boot/initrd.img-3.16.0-4-amd64 /tmp/initrd
$ cat /etc/xen/debtest1.conf
name       = "debtest1"
memory     = 1024
vcpus      = 2
vif        = [ … ]
kernel     = '/tmp/kernel'
ramdisk    = '/tmp/initrd'
extra      = 'root=UUID=38420e46-6123-477d-ba23-baeba8ac0d59 ro'
disk       = [ "phy:/dev/myvg/debtest1_xvda,xvda,w",
               "phy:/dev/myvg/debtest1_xvdb,xvdb,w",
               "phy:/dev/myvg/debtest1_xvdc,xvdc,w" ]
on_poweroff = "preserve"
on_reboot   = "preserve"
on_crash    = "preserve"

This boots fine.

What also works with the configuration in dom0 as described in
previous email:

- Installing grub-xen in guest and chainloading to that

- Installing grub-pc in guest and using "configfile
  /boot/grub/grub.cfg"

The only thing that I can't get working is "legacy_configfile
/boot/grub/menu.lst"

Here is what the config looks like if I interrupt the boot and go to
edit it:

set root='(hd0,1)'; set legacy_hdbias='0'
legacy_kernel   '/boot/vmlinuz-3.16.0-4-amd64' '/boot/vmlinuz-3.16.0-4-amd64' 
'root=UUID=38420e46-6123-477d-ba23-baeba8ac0d59' 'ro'
legacy_initrd '/boot/initrd.img-3.16.0-4-amd64' 
'/boot/initrd.img-3.16.0-4-amd64'

Cheers,
Andy