root=805
 

Hi

I'm trying to compile the kernel but no matter what I try the reboot freezes at the following messages...

kmod: failed to exec /sbin/modprobe -s -k block-major-8, errno = 2
VFS: Cannot open root device "805" or 08:05
Please append a correct "root=" boot option
kernel panic: VFS: unable to mount root fs on 08:05

Having read around a bit, I think this means that I have to change the "root = /dev/sda5" line in /etc/lilo.conf

My question is: to what?

I have four scsi disks and an Integrated Ultra 320/M RAID 0 controller. On my MS-Win partition this has the affect of making all the disks appear as one and apparently does the same for linux.

When I installed linux (slack 9) I had to use the raid.s boot option and had to use fdisk /dev/ida/c0d0. (This was by a process of elimination rather than any deep technical knowledge on my part.) The installation went fine, though there are some configuration problems which is why I want to recompile.

I've tried changing the root= to various things (including /dev/ida/c0d0) but all that does is change the 805 code above to some other number. Also when I boot with the original vmlinuz, root=/dev/sda5 seems to cause no problem at all.

fdisk -l gives this...

Disk /dev/sda: 145.4 GB, 145450074112 bytes
255 heads, 63 sectors/track, 17683 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sda1 1 6 48163+ de Dell Utility
/dev/sda2 * 7 8628 69256215 c Win95 FAT32 (LBA)
/dev/sda3 8890 17683 70637805 5 Extended
/dev/sda4 8629 8889 2096482+ 82 Linux swap
/dev/sda5 8890 9498 4891761 83 Linux
/dev/sda6 9499 17683 65745981 83 Linux

Partition table entries are not in disk order

What should I set the root= parameter to? Or am I completely on the wrong track?

Thanks in advance,

John

is there already a root parameter in your lilo.conf? And if so is it what you wrote:

root = /dev/sda5

If it is that, then try this:

root=/dev/sda5

You can't have spaces when assigning that.

HTH, if not post back, with a list of your partitions from fdisk, and your current lilo.conf.

Mike.

Hi Mike, many thanks for the reply, but no joy, I'm afraid.

I did have spaces around the = sign but I've removed them now and it made no difference.

The fdisk information is in my original post, my lilo.conf is below.

I'd be grateful for any other ideas, I'm really stumped! Does it matter that / is mounted on a logical partition?

Thanks again,

John

# LILO configuration file
# generated by 'liloconfig'
#
# Start LILO global section
lba32
boot = /dev/sda
message = /boot/boot_message.txt
prompt
#timeout = 1200
# Override dangerous defaults that rewrite the partition table:
change-rules
reset
# Normal VGA console
vga = normal
# End LILO global section
# DOS bootable partition config begins
other=/dev/sda2
label=DOS
table=/dev/sda
# DOS bootable partition config ends
# Linux bootable partition config begins
image=/boot/vmlinuz
root=/dev/sda5
label=Linux
read-only
image=/boot/vmlinuz.orig
root=/dev/sda5
label=Linux_orig
read-only
# Linux bootable partition config ends

Hi,

So 50 reads and only one reply tells me that I'm not the only one stumped. I figure either I'm doing something wrong with the kernel compile or this is a bug of some sort, which leads me to two new questions...

I compile using the instructions in the Slackware Linux Essentials book, so I don't think I'm doing anything procedurally wrong, all I can think is that I'm including or omitting some module that is causing the problem. I've tried leaving out some modules that seemed likely to me but get the same result each time and there's too many of them to work through them all (I have to get some work done inbetween compiles :->).

So the question is, how can I compare the configuration from the working kernel with any of my compiled kernels and will this help me narrow down what is causing the problem? Obviously I have the .config file from the latter, but I presume the original .config from when I installed the source package is just a set of typical defaults and doesn't have anything to do with the kernel that I installed with? (Remembering that I installed with raid.s).

The second question is, could this be a bug, and if so how do I report it? I can't see anything at the slackware webpage.

Thanks,

John

You could compare the config files generated by "make menuconfig" or "make xconfig" for each kernel version.

Have you tried putting the config file from your old kernel in the directory with your new kernel's source and running "make oldconfig"? This will cause the same options to be chosen as were in your old kernel and then allow you to choose options that have been added to the new kernel source.