Problem running Kernel 2.6.0
 

It compiles fine but when I try to boot it I get...

Kernel panic: VFS: Unable to mount root fs on hda7

Im currently running Kernel 2.4.22 which works fine...

Any suggestions?

Try compiling the filesystem u r using into the kernel and not as a module.
ie, if u use reiserfs, compile it into the kernel not as a module.

Correct. What filesystem are you using?

I got the same poblem when I tried to use the new kernel at work.

At home (I had been trying this on a test server at work) I just downloaded the complete source again, untarred it and built the kernel. Everything *appeared* to go smoothly, until I ran the modules_install step . . . at this point, I got an error saying:

depmod: *** Unresolved symbols in /lib/modules/2.6.0/kernel/security/root_plug.ko

I assume this means I am missing some files or libraries . . . any ideas which ones I need? I am not overly competent at interpreting kernel erros messages.

Also, on my last build (2.4.20-8custom), I found it was necessary to build a new initrd image file. What is this file, what does it do, and should I build a new initrd-2.6.0.img file to go with my new kernel?

One last thing. Regarding the "patch" command and the kernel patch that can be downloaded from kernel.org . . . what is the difference between patching a system using patch or downloading and building the whole kernel? Are there any special requirements to use the patch file? I tried that first since it was so much smaller but no luck.

Sorry for asking such simple questions, but I am fairly new to patching kernels.

Thanks in advance.

Check that you didn't accidentally enable anything under the "Security options" dialog.

You don't need initrd if you compile all of your critical core drivers into the kernel.

The difference is that the patchfiles are smaller and take a LOT less time to download. If you use "make mrproper" and save your .config, you can use the exact same tree for a very long time.

Ok, that might be the problem . . . I think I did enable some of the security options. I'll unselect them and see if that works. Since I am not sure what a critical core drivers are (or which of them to select), the last few times, I have needed to use muinitrd which confused me since I had never used it before.

I will try the patch method later now that I already have the complete source downloaded.

Thanks for your help and time.

I really dont know what filesystem I am running...

Depending upon which utility I run, I get a different answer for them...

All the tools agree, that :

/dev/hda2 Type = Extended
/dev/hda5 Type = Linux Swap
/dev/hda6 Type = Linux Native (ext2)

However

one tool (Yast2) thinks that hda7 is Linux Native (ext2)

another tool (parted) reports no type for hda7

another tool (Yast) reports hda7 is reiser.

Sigh...

I am compiling the kernel with all of these filesystems as part of the kernel, not modules.

Can you tell us about the errors that are signaled before the kernel panic?

After a bit of tinkering, the message Im getting now is

VFS: Cannot open root device "307" or unknown-block(3,7)
Please append a correct "root=" boot option
Kernel Panic: VFS: Unable to mount root fs on unknown-block(3,7)

The 2.4.22 kernel still works fine.

Did you compile the IDE/SCSI chipset drivers into your kernel?

When you boot 2.4.22 type mount and it will display all your mounted partitions and also tell you what filesystem type they are. Look for the / partition or /boot if you have a /boot partition and whatever filesystem type it is you either need to build that into the kernel or you need to use initrd to pass the module to the kernel. Also look at /etc/lilo.conf and make sure the root= in the 2.6.0 section matches the root= for the 2.4.22 section. If you change anything in lilo.conf you have to save it and run lilo, before you reboot.

As for initrd it's really not that hard to use:

cd /boot
mkinitrd initrd-2.6.0.img 2.6.0

Then edit /etc/lilo.conf and add this to your 2.6.0 section
initrd=/boot/initrd-2.6.0.img

save lilo.conf
lilo
reboot

according to mount my / partition is reiser.

I have compiled the rieser filesystem driver into the kernel.

I do not have mkinitrd

Did you check /etc/lilo.conf and make sure the root= for the 2.6.0 kernel matches the root= for the 2.4 kernel?

Yes, they are the same... in lilo.conf. Both are /dev/hda7

Did you verify the ide support like TheOneKEA suggested?

Try running rdev against the new kernel and that will tell you which partition the kernel thinks is root, for instance if the kernel is /boot/vmlinuz-2.6.0 then do this.

rdev /boot/vmlinuz-2.6.0

If it is wrong then just change it like this:

rdev /boot/vmlinuz-2.6.0 /dev/hda7

Could you post /etc/lilo.conf