building kernel modules for linux differnet version

[Yann Droneaud]

Le mardi 11 mars 2014 à 22:42 +0530, Saket Sinha a écrit :
> Please find my response inline
> 
> >>          I have a scenario where I need to build a driver for
> >> different kernel versions.
> >> I have kernel-headers of different version in /lib/modules/
> >> 2.6.32-xxxx
> >> 2.6.39-xxxx
> >>
> >> and currently I am booted into 2.6.32-xxxx(which I find out by uname -r)
> >>
> >
> > You don't need to boot on a specific kernel version to build external
> > module for it.
> >
> 
> I am aware of that. I just need the kernel header of that specific
> version instead.
> What I meant was that since I was using the expression "uname -r" in
> my makefile below-
>  "make  -C   /lib/modules/$(shell uname -r)/build  M=$(PWD)  modules"
> so I specified that.
> 
> >> Now in my driver makefile, I generate .ko of driver
> >> make  -C   /lib/modules/$(shell uname -r)/build  M=$(PWD)  modules
> >>
> >> but I notice that the driver .ko gets generated for 2.6.39-xxxx though
> >> I am booted into  2.6.32-xxxx. Can anyone help me figure out why this
> >> is happening?
> >>
> >
> > Could you check that /lib/modules/2.6.32-xxxx/build is not a symbolic
> > link to linux 2.6.39-xxxx sources ?
> 
> I am pasting the output for you to check
> 
> [root at Noi1-502156 ~]# cd /lib/modules
> [root at Noi1-502156 modules]# ls
> 2.6.32-220.4.2.el6.x86_64      2.6.39-300.17.1.el6uek.x86_64
> 2.6.32-358.6.2.el6.x86_64      2.6.39-400.24.1.el6uek.x86_64
> [root at Noi1-502156 modules]# ll
> total 16
> drwxr-xr-x. 8 root root 4096 Feb 28 14:41 2.6.32-220.4.2.el6.x86_64
> drwxr-xr-x. 7 root root 4096 Jul 15  2013 2.6.32-358.6.2.el6.x86_64
> drwxr-xr-x  8 root root 4096 Aug 12  2013 2.6.39-300.17.1.el6uek.x86_64
> drwxr-xr-x. 4 root root 4096 Jul 10  2013 2.6.39-400.24.1.el6uek.x86_64
> [root at Noi1-502156 modules]#
> 

Now try "ls -dFl  /lib/modules/2.6.3*/build"

And

grep '^\(\(VERSION\)\|\(PATCHLEVEL\)\|\(SUBLEVEL\)\|\(EXTRAVERSION\)\|
\(MAKEARGS\)\)' /lib/modules/*/build/Makefile

Check that matches the expected version.

-- 
Yann Droneaud
OPTEYA