LinuxQuestions.org

LinuxQuestions.org (/questions/)
-   Linux - Laptop and Netbook (http://www.linuxquestions.org/questions/linux-laptop-and-netbook-25/)
-   -   KERNEL PANIC: Cannot execute a PAE-enabled kernel on a PAE-less CPU! (http://www.linuxquestions.org/questions/linux-laptop-and-netbook-25/kernel-panic-cannot-execute-a-pae-enabled-kernel-on-a-pae-less-cpu-548990/)

ovais370 04-25-2007 05:13 PM

KERNEL PANIC: Cannot execute a PAE-enabled kernel on a PAE-less CPU!
 
I have Dell D600, installed REL5, I have also installed kernel-xen-2.6.18-8.1.1.el5, but if I try to boot from this kernel it gives me the error "KERNEL PANIC: Cannot execute a PAE-enabled kernel on a PAE-less CPU!"


Please help how do I make this kernel non-PAE or how to disable PAE.


thanks

syg00 04-25-2007 05:37 PM

Sounds like it has HIGHMEM64G set in the kernel. Turn it off - requires a kernel recompile.
Or simply pick another kernel offering.

Not being a RHEL user I can't help with what's available.

ovais370 04-25-2007 07:56 PM

Would you know how to recompile a kernel, or do you know where to find a Xen Kernel which would work.



thanks

hollywoodb 04-25-2007 08:46 PM

afaik all the Xen-enabled kernels are also PAE enabled.

This is because any CPU that supports full virtualization via the Xen hypervisor also supports PAE.

You can do paravirtualization with Xen without the actual Xen kernel. This is similar as VMWare Workstation or VirtualBox.

The Xen kernel is a special kernel that loads Xen hypervisor, and the Xen hypervisor then loads RHEL. RHEL is then run as a virtual machine, although it doesn't actually seem that way. You can also then install other OSes under the Xen hypervisor using tools included with RHEL.

Since your system doesn't support PAE (and doesn't have the other vitualization instructions) you can't run the Xen hypervisor. You can, however, run a regular kernel, then use Xen to run paravirtualized guests under RHEL.

http://www.redhat.com/rhel/virtualization/
(see near bottom)

chuckster 10-13-2007 12:41 AM

Hi a Newby here also and I have the same exact problem as the original poster. I have a D600 with the same same error so I have to hit the esc key to load the original kernel release each time my D600 boots. I just want to remove this this xen stuff at this point to get my Ubuntu booting back the way it used to. I don't see the package listed in my uninstall options so I don't know how to remove it.

Any help would be great. The installation just plain messed up a lot of stuff with all my desktop customizations I had and plus it will not boot normally anymore because of the PAE issue.

PLEASE help me get this out of my PC...Thx :-)

syg00 10-13-2007 01:42 AM

Tell us (exactly) what you did - as in what did you install, and how.
Let's see the output of "cat /boot/grub/menu.lst"

chuckster 10-13-2007 01:03 PM

Thank you for replying.

I followed instructions on this site for the initial install:
http://blog.codefront.net/2007/06/26...newbies-guide/

So to install it I ran " apt-get install ubuntu-xen-server "

The install seemed to complete ok but then I rebooted and my D600 was stuck in a never ending loop. The last line would complain about PAE not on a PAE capable CPU (the same error as originally posted here).

I then followed instructions found here:
http://www.howtoforge.com/ubuntu_7.0...m_repositories

I retraced my steps went back through the install again and configured the config files as recommended. My D600 still loops on boot and the only past is to hit ESC and select a different kernel boot. Doing this messed up a number of things on my desktop like my screenlets for some reason all initialize on bootup into the GUI and I have to restart compiz everytime. THings have not been the same since the attempt to play around with XEN.

At this point I just want to remove so I can get everything else working properly again.

To your other request here is my menu.lst output.

# menu.lst - See: grub(8), info grub, update-grub(8)
# grub-install(8), grub-floppy(8),
# grub-md5-crypt, /usr/share/doc/grub
# and /usr/share/doc/grub-doc/.

## default num
# Set the default entry to the entry number NUM. Numbering starts from 0, and
# the entry number 0 is the default if the command is not used.
#
# You can specify 'saved' instead of a number. In this case, the default entry
# is the entry saved with the command 'savedefault'.
# WARNING: If you are using dmraid do not change this entry to 'saved' or your
# array will desync and will not let you boot your system.
default 0

## timeout sec
# Set a timeout, in SEC seconds, before automatically booting the default entry
# (normally the first entry defined).
timeout 3

## hiddenmenu
# Hides the menu by default (press ESC to see the menu)
hiddenmenu

# Pretty colours
#color cyan/blue white/blue

## password ['--md5'] passwd
# If used in the first section of a menu file, disable all interactive editing
# control (menu entry editor and command-line) and entries protected by the
# command 'lock'
# e.g. password topsecret
# password --md5 $1$gLhU0/$aW78kHK1QfV3P2b2znUoe/
# password topsecret

#
# examples
#
# title Windows 95/98/NT/2000
# root (hd0,0)
# makeactive
# chainloader +1
#
# title Linux
# root (hd0,1)
# kernel /vmlinuz root=/dev/hda2 ro
#

#
# Put static boot stanzas before and/or after AUTOMAGIC KERNEL LIST

### BEGIN AUTOMAGIC KERNELS LIST
## lines between the AUTOMAGIC KERNELS LIST markers will be modified
## by the debian update-grub script except for the default options below

## DO NOT UNCOMMENT THEM, Just edit them to your needs

## ## Start Default Options ##
## default kernel options
## default kernel options for automagic boot options
## If you want special options for specific kernels use kopt_x_y_z
## where x.y.z is kernel version. Minor versions can be omitted.
## e.g. kopt=root=/dev/hda1 ro
## kopt_2_6_8=root=/dev/hdc1 ro
## kopt_2_6_8_2_686=root=/dev/hdc2 ro
# kopt=root=UUID=9dd29c8f-c72e-4692-9b05-a75b26599970 ro

## Setup crashdump menu entries
## e.g. crashdump=1
# crashdump=0

## default grub root device
## e.g. groot=(hd0,0)
# groot=(hd0,0)

## should update-grub create alternative automagic boot options
## e.g. alternative=true
## alternative=false
# alternative=true

## should update-grub lock alternative automagic boot options
## e.g. lockalternative=true
## lockalternative=false
# lockalternative=false

## additional options to use with the default boot option, but not with the
## alternatives
## e.g. defoptions=vga=791 resume=/dev/hda5
# defoptions=quiet splash

## should update-grub lock old automagic boot options
## e.g. lockold=false
## lockold=true
# lockold=false

## Xen hypervisor options to use with the default Xen boot option
# xenhopt=

## Xen Linux kernel options to use with the default Xen boot option
# xenkopt=console=tty0

## altoption boot targets option
## multiple altoptions lines are allowed
## e.g. altoptions=(extra menu suffix) extra boot options
## altoptions=(recovery) single
# altoptions=(recovery mode) single

## controls how many kernels should be put into the menu.lst
## only counts the first occurence of a kernel, not the
## alternative kernel options
## e.g. howmany=all
## howmany=7
# howmany=all

## should update-grub create memtest86 boot option
## e.g. memtest86=true
## memtest86=false
# memtest86=true

## should update-grub adjust the value of the default booted system
## can be true or false
# updatedefaultentry=false

## ## End Default Options ##

title Xen 3.0-i386-pae / Ubuntu, kernel 2.6.19-4-server
root (hd0,0)
kernel /boot/xen-3.0-i386-pae.gz
module /boot/vmlinuz-2.6.19-4-server root=UUID=9dd29c8f-c72e-4692-9b05-a75b26599970 ro console=tty0
module /boot/initrd.img-2.6.19-4-server
quiet
savedefault

title Ubuntu, kernel 2.6.20-16-generic
root (hd0,0)
kernel /boot/vmlinuz-2.6.20-16-generic root=UUID=9dd29c8f-c72e-4692-9b05-a75b26599970 ro quiet splash
initrd /boot/initrd.img-2.6.20-16-generic
quiet
savedefault

title Ubuntu, kernel 2.6.20-16-generic (recovery mode)
root (hd0,0)
kernel /boot/vmlinuz-2.6.20-16-generic root=UUID=9dd29c8f-c72e-4692-9b05-a75b26599970 ro single
initrd /boot/initrd.img-2.6.20-16-generic

title Ubuntu, kernel 2.6.20-15-generic
root (hd0,0)
kernel /boot/vmlinuz-2.6.20-15-generic root=UUID=9dd29c8f-c72e-4692-9b05-a75b26599970 ro quiet splash
initrd /boot/initrd.img-2.6.20-15-generic
quiet
savedefault

title Ubuntu, kernel 2.6.20-15-generic (recovery mode)
root (hd0,0)
kernel /boot/vmlinuz-2.6.20-15-generic root=UUID=9dd29c8f-c72e-4692-9b05-a75b26599970 ro single
initrd /boot/initrd.img-2.6.20-15-generic

title Ubuntu, kernel 2.6.19-4-server
root (hd0,0)
kernel /boot/vmlinuz-2.6.19-4-server root=UUID=9dd29c8f-c72e-4692-9b05-a75b26599970 ro quiet splash
initrd /boot/initrd.img-2.6.19-4-server
quiet
savedefault

title Ubuntu, kernel 2.6.19-4-server (recovery mode)
root (hd0,0)
kernel /boot/vmlinuz-2.6.19-4-server root=UUID=9dd29c8f-c72e-4692-9b05-a75b26599970 ro single
initrd /boot/initrd.img-2.6.19-4-server

title Ubuntu, memtest86+
root (hd0,0)
kernel /boot/memtest86+.bin
quiet

### END DEBIAN AUTOMAGIC KERNELS LIST


Thank You for your help.
Chuck

syg00 10-13-2007 06:49 PM

Not being a big apt user, I'd expect "agt-get remove ..." should do the job.
If you just want to sort the boot issue out, try changing "default 0" to "default 1" in menu.lst
Personally I always comment out the hiddenmenu, but that's personal.


All times are GMT -5. The time now is 06:11 AM.