[boot] What do those files do?

[littlebigman]

Hello

While running "apt-file show linux-image-2.6.31-22-generic", I notice those files in /boot:

linux-image-2.6.31-22-generic: /boot/System.map-2.6.31-22-generic
linux-image-2.6.31-22-generic: /boot/abi-2.6.31-22-generic
linux-image-2.6.31-22-generic: /boot/config-2.6.31-22-generic
linux-image-2.6.31-22-generic: /boot/vmcoreinfo-2.6.31-22-generic
linux-image-2.6.31-22-generic: /boot/vmlinuz-2.6.31-22-generic

Does someone know what those files do exactly? Why is there no initrd.(gz/lz), since I read that to keep the kernel (vmlinuz) small, most drivers are not part of it and must be loaded dynamically (from initrd while the kernel is still booting up, and from the real root filesystem once the mass-storage can be mounted)?

Thank you.

[GNU-Fan]

linux-image-2.6.31-22-generic: /boot/System.map-2.6.31-22-generic

A system map is where the connections between symbol names and memory addresses are made. This is needed if other programs have to use kernel functions. They know the names of it, but they don't know where they are located. This is different for each kernel.

[quote]
linux-image-2.6.31-22-generic: /boot/config-2.6.31-22-generic
[quote]
These are the answers to the questions when you configured the kernel.
Like if a certain driver is to be included (Y/N) in the kernel.

linux-image-2.6.31-22-generic: /boot/vmlinuz-2.6.31-22-generic

This is the "core" kernel itself. Without the modules.

Why is there no initrd.(gz/lz), since I read that to keep the kernel (vmlinuz) small, most drivers are not part of it and must be loaded dynamically (from initrd while the kernel is still booting up, and from the real root filesystem once the mass-storage can be mounted)?

This is true, but an initrd is not mandatory. If you compile the vital drivers statically into the kernel, you don't need the interim step of a ramdisk.

[littlebigman]

Thanks for the explanations.