Re: Re : Re : Which kernel may I compile ?

Emmanuel COURCELLE
Thu, 05 Jan 2012 09:09:01 -0000

Hi David
thanks for your answer.

I did exactly as suggested:

1/ download the 2.6.32.50 kernel
2/ cd /usr/src/xen...
3/ cp /boot/config-2.6.32-5-xen-amd64 .config
4/ vi .config and change CONFIG_XEN_MAX_DOMAIN_MEMORY=32 to
CONFIG_XEN_MAX_DOMAIN_MEMORY=128
5/ make oldconfig
6/ make, mkinitrd, update-grub2
7/ reboot:
        ==> reboot with the new kernel alone (ie WITHOUT the xen
hypervisor): OK
        ==> reboot with the xen hypervisor: the xen stage is OK, but
after memory scrub the kernel is loaded, and it runs in panic after a
couple of seconds, telling that it cannot find root fs VFS block(0,0)
not found or something like this (after 1 second the screen blanks and
the machine automatically reboots, so it is difficult to read the
precise message).

So the question is:

A/ Do I make something wrong ?
B/ If not, do I have a problem with the CONFIG_XEN_MAX_DOMAIN_MEMORY or
the xen version ?

The server is a Dell Poweredge R710, 2CPUS with 6 cores each, 128Gb memory
The xen version is:

# xm info
host                   : moxen
release                : 2.6.32-5-xen-amd64
version                : #1 SMP Mon Oct 3 07:53:54 UTC 2011
machine                : x86_64
nr_cpus                : 12
nr_nodes               : 2
cores_per_socket       : 6
threads_per_core       : 1
cpu_mhz                : 2660
hw_caps                :
bfebfbff:2c100800:00000000:00001f40:029ee3ff:00000000:00000001:00000000
virt_caps              : hvm hvm_directio
total_memory           : 131059
free_memory            : 9092
node_to_cpu            : node0:0,2,4,6,8,10
                          node1:1,3,5,7,9,11
node_to_memory         : node0:6
                          node1:9086
node_to_dma32_mem      : node0:0
                          node1:2990
max_node_id            : 1
xen_major              : 4
xen_minor              : 0
xen_extra              : .1
xen_caps               : xen-3.0-x86_64 xen-3.0-x86_32p hvm-3.0-x86_32
hvm-3.0-x86_32p hvm-3.0-x86_64
xen_scheduler          : credit
xen_pagesize           : 4096
platform_params        : virt_start=0xffff800000000000
xen_changeset          : unavailable
xen_commandline        : dom0_mem=512M dom0_max_vcpus=1 dom0_vcpus_pin
loglvl=all guest_loglvl=all
cc_compiler            : gcc version 4.4.5 (Debian 4.4.5-8)
cc_compile_by          : waldi
cc_compile_domain      : debian.org
cc_compile_date        : Sun Nov  6 09:42:15 CET 2011
xend_config_format     : 4


The grub entries are (the first two entries work, the last ends in a panic)

menuentry ''Debian GNU/Linux, with Linux 2.6.32.50'' --class
debian
--class gnu-linux --class gnu --class os {
     insmod part_msdos
     insmod ext2
     set root=''(hd2,msdos1)''
     search --no-floppy --fs-uuid --set 1939b8fd-e856-4762-a6ca-76e0b9be0f36
     echo    ''Loading Linux 2.6.32.50 ...''
     linux    /boot/vmlinuz-2.6.32.50
root=UUID=1939b8fd-e856-4762-a6ca-76e0b9be0f36 ro  quiet
     echo    ''Loading initial ramdisk ...''
     initrd    /boot/initrd.img-2.6.32.50
}

menuentry "Xen 4.0" {
     insmod ext2
     set root=''(hd1,1)''
     multiboot /boot/xen-4.0-amd64.gz dom0_mem=512M dom0_max_vcpus=1
dom0_vcpus_pin loglvl=all guest_loglvl=all
     search --no-floppy --fs-uuid --set 1939b8fd-e856-4762-a6ca-76e0b9be0f36
     module /boot/vmlinuz-2.6.32-5-xen-amd64 dummy=dummy
root=UUID=1939b8fd-e856-4762-a6ca-76e0b9be0f36 ro
     module /boot/initrd.img-2.6.32-5-xen-amd64
}

menuentry "Xen 4.0 2.6.32.50" {
     insmod ext2
     set root=''(hd1,1)''
     multiboot /boot/xen-4.0-amd64.gz dom0_mem=512M dom0_max_vcpus=1
dom0_vcpus_pin loglvl=all guest_loglvl=all
     search --no-floppy --fs-uuid --set 1939b8fd-e856-4762-a6ca-76e0b9be0f36
     module /boot/vmlinuz-2.6.32.50 dummy=dummy
root=UUID=1939b8fd-e856-4762-a6ca-76e0b9be0f36 ro
     module /boot/initrd.img-2.6.32.50
}

I attach to this mail the two configuration files (one provided by
Debian, the other is the output of make oldconfig)

Thanks again for your help !

--
Emmanuel COURCELLE                emmanuel.courcelle@toulouse.inra.fr