Manual kernel build always adds "+" to vermagic — insmod fails

General Discussion
1

Board: BeagleBone Black Rev C Kernel: 6.18.42 (target: 6.18.42-bone46) Build system: bb-kernel’s build_kernel.sh

Problem

Building with build_kernel.sh out of the box gave a vermagic the board suffix :

vermagic: 6.18.44-bone47 SMP preempt mod_unload ARMv7 thumb2 p2v8

Then after i tried Intree Device Driver building and got vermagic the board suffix :

vermagic: 6.18.44+ SMP preempt mod_unload ARMv7 thumb2 p2v8

So I went into make menuconfig and manually set:

CONFIG_LOCALVERSION="-bone46"
CONFIG_LOCALVERSION_AUTO=n

Then rebuilt. The suffix now shows up correctly, but the + is still there:

vermagic: 6.18.44-bone47+ SMP preempt mod_unload ARMv7 thumb2 p2v8

insmod fails with Invalid module format since this doesn’t match the running kernel’s uname -r (6.18.42-bone46, no +).

What I’ve tried

  • Confirmed .config has CONFIG_LOCALVERSION="-bone46" and # CONFIG_LOCALVERSION_AUTO is not set

  • Added an empty .scmversion file at the kernel tree root to stop scripts/setlocalversion from checking git dirty state

  • Deleted include/config/kernel.release and include/generated/utsrelease.h to force regeneration

  • Re-ran make modules — + persists regardless

Question

Why does the + remain even with LOCALVERSION set and LOCALVERSION_AUTO off? Is build_kernel.sh doing something (git state, separate version file, script patch) that’s still appending it after my menuconfig change? What’s the correct way to get a clean 6.18.42-bone46 with no + when manually editing config on top of a build_kernel.sh tree?

2

Run a git status inside the linux folder and see what’s going on…

If you want the tree to be “clean” prior to build, just git commit the changes and build again.

3

Install everything in the deploy directory, kernel, modules, and device trees. Or just use build_deb.sh to generate a Deb package with everything… Your build environment (gcc version, etc) does not 100% match the 6.18.44-bone47 distro build, so it’s going to throw that mismatch error, when using pieces from two kernel builds… Otherwise the magic is. LOCALVERSION=${BUILD} on the build line