Installing kernel sources

[anarcholinuxism]

Hi,

I'm trying to follow this how-to

http://www.ruault.com/Zaurus/ethernet-over-usb-howto.html

to get my zaurus and my Debian (2.4.18) talking.

It gives 2 options (one only implied) either apply the patch or update the kernel, neither of which I have manged to work out how to do.

1) update my kernel - with debian this is something like apt-get install kernel-image-XXXXXX but I can't work out the corect syntax cos I just keep getting package not found

2) apply the patch - in the HOWTO step 1 it says "Assuming your Linux sources are in /usr/src/linux do the following :" which of course they're not, I'm not even sure how if they're on the machine at all, or how to get them if they're not.

Any suggestions appreciated.

[hard candy]

If there is nothing in the /usr/src directory, you need to download the kernel sources. /usr/src/linux is a symbolic link to the kernel sources. You can make or restore the link by:
1. rm /usr/src/linux
2. ln -s /usr/src/linux /usr/src/"the kernel sources".

[Satanic Atheist]

If you can grab the kernel-source in tar.gz form and I suggest you get kernel 2.4.20 (2.4.21 has problems apparently) then do this:

> mv kernel-source...tar.gz /usr/src
> cd /usr/src
> tar -zxvf kernel-source...tar.gz

And create the symlink as hard candy suggests.

This should then stick it in the right place.

To patch the kernel, stick the patches in the /usr/src and change to the source directory (/usr/src/linux).

> patch -p1 < ../YOURPATCHNAME

Should patch your kernel. Make sure it actually works (no failed hunks), otherwise you'll have to find the right patch.

Although I rarely bother to patch the kernel, I test each patch until I know that each works. If one fails, I remove the kernel source tree and replace it with a vanilla source. This makes sure that nothing's gone astray (OK - called me paranoid, I could just reverse out the patch, but I'd rather not mess around compiling for ages because of one duff patch).

Interestingly enough, I managed to get hold of the Supermount patch for 2.4.20. It took me AGES to find it in the right format, but if you'd like to get a copy I can e-mail it to you (I don't want to post stuff like patches here).

James

[GaryJones32]

if you want to see what kernel binaries are available for your debian
flavor use:
apt-cache search kernel

[mdwatts]

Originally posted by hard candy

2. ln -s /usr/src/linux /usr/src/"the kernel sources".

Actually that should be the other way around.

ln -s /usr/src/linux-#.#.# /usr/src/linux

i.e.

ln -s /usr/src/linux-2.4.21 /usr/src/linux

[anarcholinuxism]

right, trying to pull out the relevant advice (that I understand) from the above replies,

I've done the following

apt-get install kernel-source-2.4.18

I've stuck with this kernel because the howto either says to patch the kernel or upgrade to 2.4.22 which I can't find the kernel-image of with apt-cache search.

The sources downloaded fine to /usr/src/ as /kernel-source-2.4.18.tar.bz2

which I unzipped and then ran

ln -s /usr/src/linux /usr/src/kernel-source-2.4.18

which gave no errors. I would have expected the /linux dir in /usr/src to then appear though but it hasn't.

I then downloaded

usbdnet-2.4.18.patch.gz

and moved it to /usr/src and unzipped it, but when I cd to /usr/src/linux to apply the patch

as in

> patch -p1 < ../YOURPATCHNAME

I get the error message

bash: cd: linux: No such file or directory

if I run

ln -s /usr/src/linux /usr/src/kernel-source-2.4.18

a second time I get the error message

ln: `/usr/src/kernel-source-2.4.18/linux': File exists

what is going on here? Do I have to create the dir linux in /usr/src first before running the symbolic link creation?

[anarcholinuxism]

well I seem to have worked that out, I was doing the sym link the wrong way round so my /usr/src/linux listing is now

drwxr-sr-x 3 root src 4096 Sep 3 10:09 .
drwxrwsr-x 5 root src 4096 Sep 3 10:05 ..
lrwxrwxrwx 1 root src 29 Sep 3 09:44 kernel-source-2.4.18 -> /usr/src/kernel-source-2.4.18

which I think is correct

however applying the patch is not working out well

if I use Satanic Athiests solution of

> patch -p1 < ../YOURPATCHNAME

or in this case

patch -p1 < ../usbdnet-2.4.18.patch

I get an error message of

can't find file to patch at input line 3

and am then prompted for the correct name of the file to patch. If I then enter at the prompt "kernel-source-2.4.18 I get"

patch: **** File kernel-source-2.4.18 is not a regular file -- can't patch

and I get the same behaviour from the suggested patch command in the howto from /usr/src

zcat usbdnet-2.4.18.patch.gz | patch -p0

could there be something wrong with the sym link?

[anarcholinuxism]

I started again from scratch deleting everything except the zipped sources file and it all seems to have worked so you can safely ignore everything above :)

Now to the next step

from http://www.ruault.com/Zaurus/ethern...-usb-howto.html

Now reconfigure the kernel to support :
cd /usr/src/linux
make menuconfig
in "Code maturity level options", select "Prompt for development and/or incomplete code/drivers"
in "USB support", section "USB Network adaptors", select (as a module) "USBD Network (Encapsulated) Host-to-Host Link (EXPERIMENTAL)"
Then enter 04dd in USBD Network idVendor and 8004 in USBD Network idProduct

you'll be the first to know if I have any problems!

[anarcholinuxism]

Make sure it actually works (no failed hunks), otherwise you'll have to find the right patch.

BTW, what is a hunk?

[Satanic Atheist]

What is a hunk? (Apart from me, that is).

Haha, seriously, I haven't got a clue, but I guess it's a section of code in a modular scripted system that can be changed, which is what a patch does. If it fails, you get "rejects" throwing about all over the place and the kernel probably won't compile (nothing new there then).

Don't really worry about it - I really don't know and I'm not a programmer. Basically, if it says a hunk failed then you know your patch screwed up.

James

[mdwatts]

Originally posted by anarcholinuxism
well I seem to have worked that out, I was doing the sym link the wrong way round so my /usr/src/linux listing is now

drwxr-sr-x 3 root src 4096 Sep 3 10:09 .
drwxrwsr-x 5 root src 4096 Sep 3 10:05 ..
lrwxrwxrwx 1 root src 29 Sep 3 09:44 kernel-source-2.4.18 -> /usr/src/kernel-source-2.4.18

which I think is correct


You should create the symlink as I posted above as the others were incorrect.

ln -s /usr/src/linux-2.4.18 /usr/src/linux

The ln manpage (man ln) does explain which is the TARGET and which is the LINK NAME.

[Satanic Atheist]

Can be a little confusing, working with source and destination stuff, but am I right in assuming that the SOURCE always comes before the DESTINATION in Linux?

Also, what's the difference between hard and soft links?

James

[mdwatts]

Originally posted by Satanic Atheist
Can be a little confusing, working with source and destination stuff, but am I right in assuming that the SOURCE always comes before the DESTINATION in Linux?

Also, what's the difference between hard and soft links?

James

Actually the ln manpage (man ln) answers both of your questions.

ln [OPTION]... TARGET [LINK_NAME]

When creating hard links, each TARGET must exist.