Re: How to check if kernel sources are installed on a system?

[Willy Tarreau <willy@w.ods.org>]

On Sun, May 28, 2006 at 08:12:44PM +0200, Arjan van de Ven wrote:
> On Sun, 2006-05-28 at 13:52 -0400, Lee Revell wrote:
> > On Sun, 2006-05-28 at 19:03 +0200, Arjan van de Ven wrote:
> > > On Sun, 2006-05-28 at 15:03 +0200, Heiko Carstens wrote:
> > > > > > > How does one check the existence of the kernel source RPM (or deb) on
> > > > > > > every single distribution?.
> > > > > > > 
> > > > > > > We know that rpm -qa | grep kernel-source works on Redhat, Fedora,
> > > > > > > SuSE, Mandrake and CentOS - how about other RPM based distros? How
> > > > > > > about debian based distros?. There doesn't seem to be a a single
> > > > > > > conherent naming scheme.  
> > > > > > 
> > > > > > I'd really like to see a distro-agnostic way to retrieve the kernel
> > > > > > configuration.  /proc/config.gz has existed for soem time but many
> > > > > > distros inexplicably don't enable it.
> > > > > 
> > > > > /boot/config-`uname -r`
> > > > 
> > > > What's the reason for distros to disable /proc/config.gz?
> > > 
> > > what would be a reason to ENable it???
> > > it's double functionality that does take memory away...
> > > 
> > 
> > It sounds like there is in fact no distro agnostic way to retrieve the
> > kernel config 
> 
> /boot/config-`uname -r` goes a long way, and yes I'm ignoring the "but
> users CAN clobber the file if they use enough violence against their
> packaging system" argument entirely. That's just a bogus one.
> 
> Also... why would there really be a need for such a way? Not for
> building anything for sure.... it's for the human. And the human seems
> to just find it already (and again the boot file works well in practice
> it seems)

Well, /boot/config-`uname -r` would not work right here, as well as on
a number of people's systems that I know, simply because a solution to
avoid the awful mess in /boot is to mkdir /boot/$(uname -r) and put
your System.map, .config and bzImage there (BTW, I also put modules
there since my /lib/modules is a symlink to /boot). This way, there
is only *ONE* rm -rf to do to remove an old unused kernel. So in this
case, it would be /boot/$(uname -r)/.config.

On another subject, I find /proc/config.gz useful when debugging kernels
because this is the only *safe* way to know what was put in a given kernel
that I have booted in the middle of others. However, I agree that this
does not bring much usefulness on distro kernels.

Cheers,
Willy