I'm currently fetching the Linux sources using git (more exactly, cogito) and
have found that a "make rpm-pkg" from them breaks.  The version for which I'm
reporting this bug is the most recent head of torvalds/linux-2.6.git's master
branch (g28defbea at the moment).

The rpm-pkg target breaks because the build installs the kernel modules into
/lib/modules/2.6.21-rc5, but the rpm .spec file expects them to be in
/lib/modules/2.6.21-rc5-g28defbea.  Below is an analysis of the problem:

1. The rpm-pkg target creates a tarball of the sources for use by the rpmbuild
utility.  This tarball is created ignoring all GIT control files (by means of
the RCS_FIND_IGNORE definition in the main Makefile), as well as any other file
used by different VCS systems.

2. The kernel.spec file used to construct the RPM file is generated by the
Makefiles and scripts found in the sources extracted from git.

3. Because of 2, the .spec file contains references to the kernel version with
the git local version string added (2.6.21-rc5-g28defbea).

4. Because of 1, when the kernel is built by rpmbuild from the generated
tarball, it does not have the .git control directories available.  Hence it
deduces a different version number (2.6.21-rc5).

5. As a result, when the kernel is built, the modules end up in
/lib/modules/2.6.21-rc5, but the .spec file expects them in the
/lib/modules/2.6.21-rc5-g28defbea directory.  Boom, error.

To reproduce, clone the kernel sources by using cg-clone, configure them and
then run a "make rpm-pkg".

This has been detected using the powerpc architecture, but should happen on all
others.