Building a single kernel module on Debian.

I was trying to build snd-seq-oss.ko so I could run the old playmidi that requires OSS /dev/sequencer, but when I did the insmod I got a -1 "Invalid module format" and dmesg showed "snd_seq_oss: no symbol version for module_layout".

I found out the problem was that since I am building just the module not the kernel, I need the Module.symvers from the distro's kernel.  So the solution in this case was to install linux-headers-2.6.32-5-686 and copy the Module.symvers from there.

There's probably other ways to do it but that is what worked for me.  See steps below for future reference.

sudo -i

apt-get install linux-headers-2.6.32-5-686 linux-source-2.6.32

cd /usr/src

tar -jvxf linux-source-2.6.32.tar.bz2

ln -s linux-source-2.6.32 linux

cd linux

cp ../linux-headers-2.6.32-5-686/Module.symvers .

cp /boot/config-2.6.32-5-686 .config

   (modify .config as desired)

make oldconfig

make prepare

make modules_prepare

make SUBDIRS=scripts/mod

make SUBDIRS=path/to/module modules