Messed Slackware after attempt to compile new kernel

So I was into experimenting on how to compile a kernel.

1. downloaded linux-2.6.29.3.tar.bz2 from kernel.org
2. cp ./linux-2.6.29.3.tar.bz2 /usr/src
3. tar -xvjf linux-2.6.29.3.tar.bz2
4. cd /linux-2.6.29.3
5. make clean
6. cp ../linux-2.6.27.7/.config ./
7. make menuconfig (loaded the .config which was copied)
8. make && make install
9. make bzImage
10. cp arch/i386/boot/bzImage /boot/vmlinuz-2.6.29.3-CUSTOM
11. edited /etc/.conf
12. restarted

Then I got a tazmanian devil instead of tux in the bootloading.
Then booting stopped, with my keyboard caps lock and other lights blinking.

Next,
Booted the DVD installer, deleted, /boot/vmlinuz-2.6.29.3-CUSTOM /usr/src/linux-2.6.29.4 and /lib/modules/2.6.29.3 in an attempt to go back to my working kernel.

mounted /dev/sda5 (my /) to /mnt/
mounted /dev/sda1 (my /boot) to /mnt/boot
chroot /mnt
/sbin/lilo -b /dev/sda1
got 5 warnings, then restarted my PC.
I still got the tazmaninan devil instead of Tux, them here is the error
List of all partitions:
No filesystem could mount root, tried: romfs
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(8,5)

Keyboard lights blinking and computer freeze


Please help, regards,

Is your /etc/lilo.conf pointing to the right (original) kernel?

Try configuring it to use the 'huge' kernel, normally called /boot/vmlinuz (actually a soft link).
With the huge kernel it should boot fine, then you can start playing around again

Originally Posted by niels.horn Is your /etc/lilo.conf pointing to the right (original) kernel? Try configuring it to use the 'huge' kernel, normally called /boot/vmlinuz (actually a soft link). With the huge kernel it should boot fine, then you can start playing around again

Ok, I will boot from the DVD installer,
mount my drives in /mnt/ and chroot to /mnt,

Then edit /etc/lilo.conf.

How do I install lilo?

Is this right? /sbin/lilo -b /dev/sda ?

Thanks again

Just check the /etc/lilo.conf
It should have these lines to point to the huge kernel:

# Slackware - Huge kernel
image = /boot/vmlinuz
  root = /dev/sda2          <-- ***change this for your hard drive***
  label = Linux
  read-only

Then afterwards just run:

lilo

This is my lilo.conf

image = /boot/vmlinuz
root=/dev/sda5
label =Linux
read-only

ls -l /boot
vmlinuz
vmlinuz-generic-2.6.27.7
vmlinuz-generic-smp-2.6.27.7-smp
vmlinuz-huge-2.6.27.7
vmlinuz-huge-smp-2.6.27.7-smp
vmlinuz.old


Should I point out image to /boot/vmlinuz.old instead?

Thanks

Better point it to vmlinuz-huge-smp-2.6.27.7-smp
That should work!

One more thing. What could have happened or was there something i did that make the new compilation not work?

Well this were the steps I made
1 downloaded linux-2.6.29.3 to /usr/src
2. copied a working .config from the default 2.6.27 kernel to /usr/src/linux-2.6.29.3
3. make clean
3. make menuconfig (and loaded the .config which was copied)
4. make && make install
5. make bzImage
6. copied the bzImage to /boot/vmlinuz-2.6.29.3
7. Edited lilo and entered an entry for the new kernel.
8. Restarted, then freeze

Are there any steps which I didnt make? what other steps for me to take or commands to execute to have a new kernel. Is the making of initram the next step? How?


Regards

I *think* the problem lies in the config file you picked.
It was probably from the "generic" kernel, not the "huge" kernel.

The generic kernel is lighter and better for day-to-day use, but does not include all the modules (especially the file-system modules needed to mount ext3 / ext4 / reiser partitions etc.).

So you can go two ways:
1) use the config file from the huge kernel as a basis to configure your own kernel (copy from /boot/config-huge-smp-2.6.27.7-smp)
2) build as you did before, but you will need to create an initial ram disk (initrd). Use these steps before rebooting:

cd /boot
mkinitrd -c -k 2.6.29.3-CUSTOM -m jbd:ext3 -f ext3 -r /dev/sda5    # change ext3 if you use another file system, like ext4, reiserfs etc.

and include in your lilo.conf the line:

initrd = /boot/initrd.gz

This is how my lilo.conf looks:

# Slackware - Generic kernel
image = /boot/vmlinuz-generic-smp-2.6.29.2-smp
  initrd = /boot/initrd.gz
  root = /dev/sda2
  label = Slackware
  read-only

Hint: do not erase the configuration in lilo that points to the huge kernel. If anything goes wrong, you can use it to boot.

Then run lilo & reboot

Thank you so much for a very detailed response.

I'll try it later and notify/post here the results (and problems if any)

Regards,

Thanks niels.horn

I followed your instruction and my new kernel was booting successfully now! I have one more question though,

for the command
mkinitrd -c -k 2.6.29.3-CUSTOM -m jbd:ext3 -f ext3 -r /dev/sda5
# change ext3 if you use another file system, like ext4, reiserfs etc.

the output is initrd.gz

However, if I would compile another version of a kernel, would i create another initrd.gz? or do i just have to rename initrd.gz

You can just rename the initrd.gz, or better, use this command:

mkinitrd -c -k 2.6.29.3-CUSTOM -m jbd:ext3 -f ext3 -r /dev/sda5 -o /boot/initrd-<yourversion>.gz

The -o option defines the output file, where you replace <yourversion> with whatever you want, like the -CUSTOM tag.
Don't forget to change the 'initrd = /boot/initrd.gz' likewise in your lilo.conf

Originally Posted by jemate18 Thanks niels.horn I followed your instruction and my new kernel was booting successfully now! I have one more question though, for the command mkinitrd -c -k 2.6.29.3-CUSTOM -m jbd:ext3 -f ext3 -r /dev/sda5 # change ext3 if you use another file system, like ext4, reiserfs etc. the output is initrd.gz However, if I would compile another version of a kernel, would i create another initrd.gz? or do i just have to rename initrd.gz

You don't need an initrd if you built-in the filesystem modules.

Originally Posted by H_TeXMeX_H You don't need an initrd if you built-in the filesystem modules.

ok, if jemate18 accepts an extra exercise...

This would be done as follows:
- when in make menuconfig, go to the file systems sub-menu and change "ext3" from "M" (built as Module) to "*" (Built in).

Then compile normally and you won't need to make an initrd.
The 'jbd' module is automagically selected by the menuconfig script to be built in as well.

@H_TeXMeX_H: I didn't mention the option to build in the modules, as jemate18 is a new user and I think it is good to understand the basic process of making an initrd, changing lilo.conf, etc.

But, we're talking Slackware here - it is even better to always take it up to the next level

Sure whatever way you want to do it. I just prefer not having to worry about initrd. Just another potential complication.

That's the Slackware philosophy: the user is in control.
It's up to each individual user to decide how to do things & Slackware gives several options