why are there two instances of the kernel?

denning · 02-05-2005, 09:20 AM

I notice that a packages called kernel-ide-2.4.29-i486-1.tgz exists under slackware/a.

I suppose this installs the kernel?

Then why does the installer later ask me again what kernel i wish to install, bare.i, bareacpi.i or lowmem.i???

secesh · 02-05-2005, 09:35 AM

slack (as any distro, probably) comes with a number of kernels, because people's hardware is different.

there are readmes dedicated to explaining what each kernel is for -- but ther's the basic rule-of-thumb:

Quote:

The kernels found in directories ending with '.i' are for use on systems that
only need IDE hard drive/CD-ROM support. Those ending in '.s' contain support
for at least one type of SCSI controller in addition to the usual IDE support.

reddazz · 02-05-2005, 09:40 AM

They are configured differently, check the Slackware documentation for the differences. I always choose to use the default kernel and later on compile my own 2.6.x kernel.

denning · 02-05-2005, 09:51 AM

i know there are different kernels to choose from. What i want to know is why the kernel is given both as a tgz file AND as a bare.i/bareacpi.i/lowmem.i

what is the tgz file for?

secesh · 02-05-2005, 09:55 AM

tgz is slackware package -- that's how you install the kernel to your system

installpkg something.tgz

btmiller · 02-05-2005, 02:25 PM

I'm pretty sure the .i files are the kernel image files, i.e. something you can write to a bootdisk to boot off of. As secesh said, the tgzs are the packages.

denning · 02-06-2005, 05:24 AM

Yes, of course the tgz files are packages. I want to know why the kernel is installed as a package AND is given as a kernel image file.

iscurrah · 02-06-2005, 09:17 AM

The image file and the package contain basically the same things. The image is so that it can be used without installing (it is already installed onto your boot media). The package is there so that the kernel can be copied to your install destination - all the correct files in the correct places, permissions and ownerships setup etc...

The boot process knows how to read the image file - and then to use it, it cannot read a package file.
The install program knows how to read and process a package file, but not a boot image. To the install program, the kernel package is just a.n.other package - nothing special about it being the kernel at all.

So you need one of each. but as far as I know, there is no technical reason why the boot image could not be unpacked and installed by the install program. But you'd have to code that yourself to do so.

shilo · 02-06-2005, 10:48 AM

Denning:

I think it's a good question. Never really thought about it. Here's my guess:

I keep a copy of the Slackware-current directory on my computer, so I am going to use that as an example (I'm too lazy to dig out my install disc

). In the root directory, there is a folder called "kernels". Looking in that folder, I see:

Code:

shilo@shilo2:/var/slackware-current$ ls kernels/
1440k.img.gz  bareacpi.i/       lowmem.i/            raid.s/     xfs.s/
README.TXT    compile_kern.sh*  make-all-bootdisks*  sata.i/     zipslack.s/
VERSIONS.TXT  ibmmca.s/         makedisk*            scsi.s/
adaptec.s/    jfs.s/            modules/             scsi2.s/
ataraid.i/    loadlin16c.txt    old_cd.i/            scsi3.s/
bare.i/       loadlin16c.zip    pportide.i/          speakup.s/

Let's take a look at one of those folders:

Code:

shilo@shilo2:/var/slackware-current/kernels/bare.i$ ls
System.map.gz  bzImage  config

So, just what you'd expect. A kernel (bzImage), a System.map, and a config.

If you look at the contents of kernel-ide-2.4.29-i486.tgz, you will see that you have a kernel (vmlinuz-ide-2.4.29), a System.map (System.map-ide-2.4.29), and a config (config-ide-2.4.29). There is also the doinst.sh file which makes the symbolic links vmlinuz, System.map, and config.

Now for some guess work on my part. Note that you will be able to confirm this with "diff" if you like. I believe that during the Slackware install kernel-ide-2.4.29-i486.tgz is installed on your computer. When it comes time to select a kernel image, if I recall, you are told that if everything is working for you already you should stick with the kernel you have been using. If you change that kernel, say to bare.i, bareacpi.i or lowmem.i, then the files for that respective kernel replace the ones in the kernel-ide-2.4.29-i486.tgz package. If you leave your kernel choice the same, nothing is done.

How can you verify this? Well, you can take the kernel-ide-2.4.29-i486.tgz package from the install disc and unpack it. I believe that is just:

Code:

tar -xvzf kernel-ide-2.4.29-i486.tgz

You might want to make sure that the package is in a separate directory first so you don't make a mess (or accidentally install it because you were in the / directory).

Now, take and diff the kernel you just unpacked to each of the kernels in the kernels directory of the install disc. I think that you will find that all of those kernels are different.

Maybe I'm wrong. Check it out and see for yourself. Let us know.

denning · 02-06-2005, 11:19 AM

Thank you iscurrah and shilo! Some people finally understood what i was asking...

I will take you your suggestion, shilo, once I get some extra time, shilo. In the middle of an academic crisis at the moment