Xen project Mailing List

Thanks for the reply Andy. I tried as you suggested here is the output of the command.

> I don't know what the problem is, but this suggests it lies within
> pygrub. Try running pygrub separately to see what happens, i.e.:

> # /usr/lib/xen-4.4/bin/pygrub /dev/host-disk2-vg/guest-disk

````

$ /usr/lib/xen-4.4/bin/pygrub /dev/vps03-disk2-vg/www2-disk

Using <class 'grub.GrubConf.Grub2ConfigFile'> to parse /grub/grub.cfg

WARNING:root:grub2's saved_entry/next_entry not supported

WARNING:root:Unknown directive else

WARNING:root:...

Traceback (most recent call last):

File "/usr/lib/xen-4.4/bin/pygrub", line 873, in <module>

output_directory, not_really)

File "/usr/lib/xen-4.4/bin/pygrub", line 718, in copy_from_image

dir=output_directory)

File "/usr/lib/python2.7/tempfile.py", line 308, in mkstemp

return _mkstemp_inner(dir, prefix, suffix, flags)

File "/usr/lib/python2.7/tempfile.py", line 239, in _mkstemp_inner

fd = _os.open(file, flags, 0600)

OSError: [Errno 2] No such file or directory: '/var/run/xend/boot/boot_kernel.jedvP5'

````

Directory /var/run/xend/boot/ don't exist in the host Xen Ubuntu14.04 of the Guest Ubuntu 16.04. Guest VM still fails to reboot after a kernel upgrade, unless I manually select the old kernel.

On Thu, Jan 11, 2018 at 11:53 AM, Michael Barkdoll <mabarkdoll@xxxxxxxxx> wrote:

Hello, I have an Ubuntu 14.04 running Xen and a VM running Ubuntu 16.04 LTS that I'm having issues with it booting after upgrading the kernel for meltdown and spectre vulnerability.

````
sudo apt-get update
sudo apt-get upgrade
sudo apt-get dist-upgrade
````

Ubuntu 14.04 xen host reboot failure log:
````
$ tailf /var/log/xen/servername.log
Domain 24 needs to be cleaned up: destroying the domain
Done. Rebooting now
libxl: error: libxl_bootloader.c:628:bootloader_finished: bootloader failed - consult logfile /var/log/xen/bootloader.27.log
libxl: error: libxl_exec.c:118:libxl_report_child_exitstatus: bootloader [-1] exited with error status 1
libxl: error: libxl_create.c:1024:domcreate_rebuild_done: cannot (re-)build domain: -3
````

````
cat /var/log/xen/bootloader.27.log
Using <class 'grub.GrubConf.Grub2ConfigFile'> to parse /grub/grub.cfg pyGRUB version 0.6
┌────────────────────────────────────────────────────────────────────────┐
│ Ubuntu │
│ Ubuntu, with Linux 4.4.0-109-generic │
│ Ubuntu, with Linux 4.4.0-109-generic (recovery mode) │
│ Ubuntu, with Linux 4.4.0-108-generic │
│ Ubuntu, with Linux 4.4.0-108-generic (recovery mode) │
│ Ubuntu, with Linux 4.4.0-104-generic │
│ Ubuntu, with Linux 4.4.0-104-generic (recovery mode) │
│ Ubuntu, with Linux 4.4.0-15-generic │
└────────────────────────────────────────────────────────────────────────┘
Use the ^ and ┴ keys to select which entry is highlighted.
Press enter to boot the selected OS, 'e' to edit the
commands before booting, 'a' to modify the kernel arguments
before booting, or 'c' for a command line.

Traceback (most recent call last):
File "/usr/lib/xen-4.4/bin/pygrub", line 905, in <module>
os.write(fd, ostring)
OSError: [Errno 28] No space left on device
````

I was able to get the vm to boot only by rapidly attempt to access the menu options and boot the old kernel (4.4.0-15-generic). Disk space and inodes seems fine on the host Ubuntu 14.04LTS and Ubuntu 16.04LTS Guest.

Ubuntu 14.04 Host:
````
root@host:/var/log/xen# df -hFilesystem Size Used Avail Use% Mounted on
udev 197M 12K 197M 1% /dev
tmpfs 42M 1.1M 41M 3% /run
/dev/dm-0 104G 49G 50G 50% /
none 4.0K 0 4.0K 0% /sys/fs/cgroup
none 5.0M 0 5.0M 0% /run/lock
none 208M 0 208M 0% /run/shm
none 100M 0 100M 0% /run/user
/dev/sda1 236M 40M 184M 18% /boot
root@host:/var/log/xen# df -hi
Filesystem Inodes IUsed IFree IUse% Mounted on
udev 50K 721 49K 2% /dev
tmpfs 52K 849 52K 2% /run
/dev/dm-0 6.6M 86K 6.5M 2% /
none 52K 2 52K 1% /sys/fs/cgroup
none 52K 5 52K 1% /run/lock
none 52K 1 52K 1% /run/shm
none 52K 2 52K 1% /run/user
/dev/sda1 61K 298 61K 1% /boot
root@host:/var/log/xen#
````

Ubuntu 16.04 PV Guest:
````
root@guest:~# df -hFilesystem Size Used Avail Use% Mounted on
udev 950M 0 950M 0% /dev
tmpfs 200M 3.1M 197M 2% /run
/dev/mapper/guest--vg-root 47G 4.3G 40G 10% /
tmpfs 997M 0 997M 0% /dev/shm
tmpfs 5.0M 0 5.0M 0% /run/lock
tmpfs 997M 0 997M 0% /sys/fs/cgroup
/dev/xvda1 472M 192M 256M 43% /boot
tmpfs 200M 0 200M 0% /run/user/1000
root@www2:~# df -hi
Filesystem Inodes IUsed IFree IUse% Mounted on
udev 238K 406 237K 1% /dev
tmpfs 250K 491 249K 1% /run
/dev/mapper/guest--vg-root 3.0M 177K 2.8M 6% /
tmpfs 250K 1 250K 1% /dev/shm
tmpfs 250K 7 250K 1% /run/lock
tmpfs 250K 16 250K 1% /sys/fs/cgroup
/dev/xvda1 122K 315 122K 1% /boot
tmpfs 250K 4 250K 1% /run/user/1000
root@guest:~#
````

Here is the guest Ubuntu 16.04 OS kernels:
````
root@guest:~# dpkg -l | grep linux-image-
ii linux-image-4.4.0-104-generic 4.4.0-104.127 amd64 Linux kernel image for version 4.4.0 on 64 bit x86 SMP
ii linux-image-4.4.0-108-generic 4.4.0-108.131 amd64 Linux kernel image for version 4.4.0 on 64 bit x86 SMP
ii linux-image-4.4.0-109-generic 4.4.0-109.132 amd64 Linux kernel image for version 4.4.0 on 64 bit x86 SMP
ii linux-image-4.4.0-15-generic 4.4.0-15.31 amd64 Linux kernel image for version 4.4.0 on 64 bit x86 SMP
ii linux-image-extra-4.4.0-104-generic 4.4.0-104.127 amd64 Linux kernel extra modules for version 4.4.0 on 64 bit x86 SMP
ii linux-image-extra-4.4.0-108-generic 4.4.0-108.131 amd64 Linux kernel extra modules for version 4.4.0 on 64 bit x86 SMP
ii linux-image-extra-4.4.0-109-generic 4.4.0-109.132 amd64 Linux kernel extra modules for version 4.4.0 on 64 bit x86 SMP
ii linux-image-extra-4.4.0-15-generic 4.4.0-15.31 amd64 Linux kernel extra modules for version 4.4.0 on 64 bit x86 SMP
ii linux-image-generic 4.4.0.109.114 amd64 Generic Linux kernel image
root@guest:~#
````

I'm currently able to boot to 4.4.0-15.31

Here is my xen config file that I use to start the vm:
````
# cat /etc/xen/guest.cfg
# /var/lib/xen/images/ubuntu-netboot/xenial16LTS

name = "guest"

#kernel = "/var/lib/xen/images/ubuntu-netboot/xenial16LTS/vmlinuz"
#ramdisk = "/var/lib/xen/images/ubuntu-netboot/xenial16LTS/initrd.gz"
bootloader = "/usr/lib/xen-4.4/bin/pygrub"

memory = 2048
vcpus = 1

disk = [ '/dev/host-disk2-vg/guest-disk,raw,xvda,rw' ]

#
# Networking
#
vif = [ 'ip=xxx.xxx.xxx.xxx ,mac=AA:BB:CC:DD:EE:FF' ]

#
# Behaviour
#
_on_poweroff_ = 'destroy'
on_reboot = 'restart'
on_crash = 'restart'
````

I also tried launching the vm with strace output of
````
strace xl create -c file.cfg
````
is here: https://pastebin.com/8ctS3TQh

I'm a bit lost as to the cause of this... I was hoping to just upgrade the kernel for meltdown and spetre, but this issue I've never faced before. I think it might be related to pygrub and the new kernel? I don't know for sure though anything I can check to figure this out better? Thanks.

Re: [Xen-users] Xen PV Guest won't boot latest kernel- OSError: [Errno 28] No space left on device