Bug#1106709: rtpengine-kernel-dkms: module fails to build for Linux 6.15: support for EXTRA_CFLAGS was removed

[Andreas Beckmann]

Package: rtpengine-kernel-dkms
Version: 12.5.1.31-1
Severity: important
Tags: upstream sid forky

Hi,

rtpengine-kernel-dkms fails to build the module(s) for Linux 6.15 in
experimental:

DKMS (dkms-3.2.0) make.log for rtpengine/12.5.1.31 for kernel 6.15-rc7-amd64 (x86_64)
Sat May 24 21:53:45 UTC 2025

Building module(s)
# command: make -j14 KERNELRELEASE=6.15-rc7-amd64 -C /lib/modules/6.15-rc7-amd64/build M=/var/lib/dkms/rtpengine/12.5.1.31/build RTPENGINE_VERSION=12.5.1.31
make: Entering directory '/usr/src/linux-headers-6.15-rc7-amd64'
make[1]: Entering directory '/var/lib/dkms/rtpengine/12.5.1.31/build'
/var/lib/dkms/rtpengine/12.5.1.31/build/gen-rtpengine-kmod-flags >/var/lib/dkms/rtpengine/12.5.1.31/build/rtpengine-kmod.mk
  CC [M]  xt_RTPENGINE.o
In file included from /usr/src/linux-headers-6.15-rc7-common/include/asm-generic/bug.h:22,
                 from /usr/src/linux-headers-6.15-rc7-common/arch/x86/include/asm/bug.h:103,
                 from /usr/src/linux-headers-6.15-rc7-common/arch/x86/include/asm/alternative.h:9,
                 from /usr/src/linux-headers-6.15-rc7-common/arch/x86/include/asm/barrier.h:5,
                 from /usr/src/linux-headers-6.15-rc7-common/include/linux/list.h:11,
                 from /usr/src/linux-headers-6.15-rc7-common/include/linux/module.h:12,
                 from xt_RTPENGINE.c:2:
xt_RTPENGINE.c: In function 'init':
xt_RTPENGINE.c:6618:78: error: 'RTPENGINE_VERSION' undeclared (first use in this function)
 6618 |         printk(KERN_NOTICE "Registering xt_RTPENGINE module - version %s\n", RTPENGINE_VERSION);
      |                                                                              ^~~~~~~~~~~~~~~~~
/usr/src/linux-headers-6.15-rc7-common/include/linux/printk.h:479:33: note: in definition of macro 'printk_index_wrap'
  479 |                 _p_func(_fmt, ##__VA_ARGS__);                           \
      |                                 ^~~~~~~~~~~
xt_RTPENGINE.c:6618:9: note: in expansion of macro 'printk'
 6618 |         printk(KERN_NOTICE "Registering xt_RTPENGINE module - version %s\n", RTPENGINE_VERSION);
      |         ^~~~~~
xt_RTPENGINE.c:6618:78: note: each undeclared identifier is reported only once for each function it appears in
 6618 |         printk(KERN_NOTICE "Registering xt_RTPENGINE module - version %s\n", RTPENGINE_VERSION);
      |                                                                              ^~~~~~~~~~~~~~~~~
/usr/src/linux-headers-6.15-rc7-common/include/linux/printk.h:479:33: note: in definition of macro 'printk_index_wrap'
  479 |                 _p_func(_fmt, ##__VA_ARGS__);                           \
      |                                 ^~~~~~~~~~~
xt_RTPENGINE.c:6618:9: note: in expansion of macro 'printk'
 6618 |         printk(KERN_NOTICE "Registering xt_RTPENGINE module - version %s\n", RTPENGINE_VERSION);
      |         ^~~~~~
make[3]: *** [/usr/src/linux-headers-6.15-rc7-common/scripts/Makefile.build:208: xt_RTPENGINE.o] Error 1
make[2]: *** [/usr/src/linux-headers-6.15-rc7-common/Makefile:2027: .] Error 2
make[1]: *** [/usr/src/linux-headers-6.15-rc7-common/Makefile:260: __sub-make] Error 2
make[1]: Leaving directory '/var/lib/dkms/rtpengine/12.5.1.31/build'
make: *** [/usr/src/linux-headers-6.15-rc7-common/Makefile:260: __sub-make] Error 2
make: Leaving directory '/usr/src/linux-headers-6.15-rc7-amd64'

# exit code: 2
# elapsed time: 00:00:03
----------------------------------------------------------------


This is most likely caused by the usage of deprecated EXTRA_CFLAGS
(superseded by ccflags-y since 2007) where the backwards compatibility
support has been removed in v6.15-rc1, finally.
https://github.com/torvalds/linux/commit/e966ad0edd0056c7491b8f23992c11734ab61ddf

Andreas