If the kernel compiles ok but booting never works and it always complains with a kernel panic about /sbin/modprobe.
Solution: You did not create initrd image file. See the Appendix A at Creating initrd.img file. Also, you must do 'make modules' and 'make modules_install' in addition to creating the initrd image file.
Sympton: After you build the kernel and reboot, the system hangs just before LILO.
Reason: Probably you did not set the BIOS to pick up the proper Primary Master IDE and Secondary Slave IDE hard disk partition.
Solution: Power on the machine and press DEL key to do setup of the BIOS (Basic Input Output system). Select the IDE settings and set proper primary hard disk partition and slave drives. When the system boots it looks for the primary IDE hard disk and the Master Boot Record partition. It reads the MBR and starts loading the Linux Kernel from the hard disk partition.
The following mistake is commited very frequently by new users.
If your new kernel does not boot and you get -
Warning: unable to open an initial console Kernel panic: no init found. Try passing init= option to kernel
The kernel looks for the init command which is located in /sbin/init. And /sbin directory lives on the root partition. For details see -
bash# man init
The 'make', 'make bzImage', 'make modules' or 'make modules_install' gives compile problems. You should give 'make mrproper' before doing make.
bash# make mrproper
bash# export TERM=VT100 bash# make menuconfig
When you run
depmod it gives "Unresolved symbols". A sample error message
is given here to demonstrate the case:
bash$ su - root bash# man depmod bash# depmod depmod: *** Unresolved symbols in /lib/modules/version/kernel/drivers/md/linear.o depmod: *** Unresolved symbols in /lib/modules/version/kernel/drivers/md/multipath.o depmod: *** Unresolved symbols in /lib/modules/version/kernel/drivers/md/raid0.o depmod: *** Unresolved symbols in /lib/modules/version/kernel/drivers/md/raid1.o depmod: *** Unresolved symbols in /lib/modules/version/kernel/drivers/md/raid5.o
Reason: You did not make modules and install the modules after building
the new kernel with
Solution: After you build the new kernel, you must do:
bash$ su - root bash# cd /usr/src/linux bash# make modules bash# make modules_install
When you boot kernel and system tries to load any modules and you get "Unresolved symbol : __some_function_name" then it means that you did not clean compile the modules and kernel. It is mandatory that you should do make clean and make the modules. Do this -
bash# cd /usr/src/linux bash# make dep bash# make clean bash# make mrproper bash# nohup make bzImage & bash# tail -f nohup.out (.... to monitor the progress) bash# make modules bash# make modules_install
If the kernel fails to load a module (say loadable module for network card or other devices), then you may want to try to build the driver for device right into the kernel. Sometimes loadable module will NOT work and the driver needs to be built right inside the kernel. For example - some network cards do not support loadable module feature - you MUST build the driver of the network card right into linux kernel. Hence, in 'make xconfig' you MUST not select loadable module for this device.
You can install default loadable modules with -
The step given below may not be required but is needed ONLY FOR EMERGENCIES where your /lib/modules files are damaged. If you already have the /lib/modules directory and in case you want replace them use the --force to replace the package and select appropriate cpu architecture.
For new versions of linux redhat linux 6.0 and later, the kernel modules are included with kernel-2.2*.rpm. Install the loadable modules and the kernel with
This will list the already installed package. bash# rpm -qa | grep -i kernel bash# rpm -U --force /mnt/cdrom/Redhat/RPMS/kernel-2.2.14-5.0.i686.rpm (or) bash# rpm -U --force /mnt/cdrom/Redhat/RPMS/kernel-2.2.14-5.0.i586.rpm (or) bash# rpm -U --force /mnt/cdrom/Redhat/RPMS/kernel-2.2.14-5.0.i386.rpm
This is only for old versions of redhat linux 5.2 and before. Boot new kernel and install the loadable modules from RedHat Linux "contrib" cdrom
bash# rpm -i /mnt/cdrom/contrib/kernel-modules*.rpm ....(For old linux systems which do not have insmod pre-installed)
More problems. You can read the /usr/src/linux/README (at least once) and also /usr/src/linux/Documentation.
If your new kernel does really weird things after a routine kernel upgrade,
chances are you forgot to
make clean before compiling the new
kernel. Symptoms can be anything from
your system outright crashing, strange I/O problems, to crummy
performance. Make sure you do a
make dep, too.
If your kernel is sucking up a lot of memory, is too large, and/or just takes forever to compile even when you've got your new Quadbazillium-III/4400 working on it, you've probably got lot of unneeded stuff (device drivers, filesystems, etc) configured. If you don't use it, don't configure it, because it does take up memory. The most obvious symptom of kernel bloat is extreme swapping in and out of memory to disk; if your disk is making a lot of noise and it's not one of those old Fujitsu Eagles that sound like like a jet landing when turned off, look over your kernel configuration.
You can find out how much memory the kernel is using by taking the
total amount of memory in your machine and subtracting from it the
amount of ``total mem'' in
/proc/meminfo or the output of the command
Configuration options for PCs are: First, under the category `General Setup', select `Parallel port support' and `PC-style hardware'. Then under `Character devices', select `Parallel printer support'.
Then there are the names. Linux 2.2 names the printer devices differently
than previous releases. The upshot of this is that if you had an
under your old kernel, it's probably an
lp0 under your new one.
dmesg' or look through the logs in
/var/log to find
If it does not compile, then it is likely that a patch failed, or your
source is somehow corrupt. Your version of gcc also might not
be correct, or could also be corrupt (for example, the include files
might be in error). Make sure that the symbolic links which
Linus describes in the
README are set up correctly. In general, if
a standard kernel
does not compile, something is seriously wrong with the system, and
reinstallation of certain tools is probably necessary.
In some cases, gcc can crash due to hardware problems. The error message will be something like ``xxx exited with signal 15'' and it will generally look very mysterious. I probably would not mention this, except that it happened to me once - I had some bad cache memory, and the compiler would occasionally barf at random. Try reinstalling gcc first if you experience problems. You should only get suspicious if your kernel compiles fine with external cache turned off, a reduced amount of RAM, etc.
It tends to disturb people when it's suggested that their hardware has problems. Well, I'm not making this up. There is an FAQ for it -- it's at http://www.bitwizard.nl/sig11.
You did not run LILO, or it is not configured correctly. One thing that
``got'' me once was a problem in the config file; it said
boot = /dev/hda1'
instead of `
boot = /dev/hda' (This can be really annoying at first,
but once you have a working config file, you shouldn't need to
Ooops! The best thing you can do here is to boot off of a floppy disk or
prepare another bootable floppy (such as `
make zdisk' would do).
You need to know where your root (
/) filesystem is and what type
it is (e.g. second extended, minix). In the example below, you also need
to know what filesystem your
tree is on, its type, and where it is normally mounted.
In the following example,
/dev/hda1, and the
filesystem which holds
/dev/hda3, normally mounted at
/usr. Both are
second extended filesystems. The working kernel image in
/usr/src/linux/arch/i386/boot is called
The idea is that if there is a functioning
bzImage, it is possible to use that
for the new floppy. Another alternative, which may or may not work better
(it depends on the particular method in which you messed up your system) is
discussed after the example.
First, boot from a boot/root disk combo or rescue disk, and mount the filesystem which contains the working kernel image:
mkdir /mnt mount -t ext2 /dev/hda3 /mnt
mkdir tells you that the directory already exists, just ignore
cd to the place where the working kernel image was. Note
/mnt + /usr/src/linux/arch/i386/boot - /usr = /mnt/src/linux/arch/i386/bootPlace a formatted disk in drive ``A:'' (not your boot or root disk!), dump the image to the disk, and configure it for your root filesystem:
cd /mnt/src/linux/arch/i386/boot dd if=bzImage of=/dev/fd0 rdev /dev/fd0 /dev/hda1
/ and unmount the normal
cd / umount /mnt
You should now be able to reboot your system as normal from this floppy. Don't forget to run lilo (or whatever it was that you did wrong) after the reboot!
As mentioned above, there is another common alternative. If you
happened to have a working kernel image in
for example), you can use that for a boot disk. Supposing all of the above
conditions, and that my kernel image is
/vmlinuz, just make these
alterations to the example above: change
note explaining how to derive
/mnt/src/linux may be ignored.
Using LILO with big drives (more than 1024 cylinders) can cause problems. See the LILO mini-HOWTO or documentation for help on that.
This can be a severe problem. Starting with a kernel release
after Linux v1.0 (around 20 Apr 1994), a program called `
periodically flushes out the filesystem buffers, was upgraded/replaced. Get
the sources to `
(you should find it where you got your kernel source), and install it (you
probably want to run your system under the old kernel while doing this). It
installs itself as `
update' and after a reboot, the new kernel
should no longer complain.
Strangely enough, lot of people cannot get their ATAPI drives working, probably because there are a number of things that can go wrong.
If your CD-ROM drive is the only device on a particular IDE interface, it must be jumpered as ``master'' or ``single.'' Supposedly, this is the most common error.
Creative Labs (for one) has put IDE interfaces on their sound cards now. However, this leads to the interesting problem that while some people only have one interface to being with, many have two IDE interfaces built-in to their motherboards (at IRQ15, usually), so a common practice is to make the soundblaster interface a third IDE port (IRQ11, or so I'm told).
This causes problems with older Linux versions like 1.3 and below. in that versions Linux don't support a third IDE interface. To get around this, you have a few choices.
If you have a second IDE port already, chances are that you are not using it or it doesn't already have two devices on it. Take the ATAPI drive off the sound card and put it on the second interface. You can then disable the sound card's interface, which saves an IRQ anyway.
If you don't have a second interface, jumper the sound card's interface (not the sound card's sound part) as IRQ15, the second interface. It should work.
Get new versions of the
route program and any other programs
which do route manipulation.
/usr/include/linux/route.h (which is actually a file in
/usr/src/linux) has changed.
Don't use the
vmlinux file created in
your boot image;
[..]/arch/i386/boot/bzImage is the right
Change the word
linux in the console termcap
/etc/termcap. You may also have to make a terminfo entry.
The linux kernel source includes a number of include files (the things that
.h) which are referenced by the standard ones in
/usr/include. They are typically referenced like this (where
xyzzy.h would be something in
#include <linux/xyzzy.h>Normally, there is a link called
include/linuxdirectory of your kernel source (
/usr/src/linux/include/linuxin the typical system). If this link is not there, or points to the wrong place, most things will not compile at all. If you decided that the kernel source was taking too much room on the disk and deleted it, this will obviously be a problem. Another way it might go wrong is with file permissions; if your
roothas a umask which doesn't allow other users to see its files by default, and you extracted the kernel source without the
p(preserve filemodes) option, those users also won't be able to use the C compiler. Although you could use the
chmodcommand to fix this, it is probably easier to re-extract the include files. You can do this the same way you did the whole source at the beginning, only with an additional argument:
blah# tar zxvpf linux.x.y.z.tar.gz linux/includeNote: ``
make config'' will recreate the
/usr/src/linuxlink if it isn't there.
The following few example commands may be helpful to those wondering how to increase certain soft limits imposed by the kernel:
echo 4096 > /proc/sys/kernel/file-max echo 12288 > /proc/sys/kernel/inode-max echo 300 400 500 > /proc/sys/vm/freepages
Закладки на сайте
Проследить за страницей
Created 1996-2021 by Maxim Chirkov
Добавить, Поддержать, Вебмастеру