Package: v4l2loopback-dkms Version: 0.13.1-1 Severity: serious DKMS make.log for v4l2loopback-0.13.1 for kernel 6.7.12-686-pae (i686) Mon May 13 09:57:13 UTC 2024
++++++ To sign the module, you must set KBUILD_SIGN_KEY/KBUILD_SIGN_CERT to point to the signing key/certificate! ++++++ For your convenience, we try to read these variables as 'mok_signing_key' resp. 'mok_certificate' from /etc/dkms/framework.conf ++++++ If your certificate requires a password, pass it via the KBUILD_SIGN_PIN env-var! ++++++ E.g. using 'export KBUILD_SIGN_PIN; read -s -p "Passphrase for signing key : " KBUILD_SIGN_PIN; sudo --preserve-env=KBUILD_SIGN_PIN make sign' Building v4l2-loopback driver... make -C /lib/modules/6.7.12-686-pae/build M=/var/lib/dkms/v4l2loopback/0.13.1/build KCPPFLAGS="" modules make[1]: Entering directory '/usr/src/linux-headers-6.7.12-686-pae' CC [M] /var/lib/dkms/v4l2loopback/0.13.1/build/v4l2loopback.o MODPOST /var/lib/dkms/v4l2loopback/0.13.1/build/Module.symvers ERROR: modpost: "__moddi3" [/var/lib/dkms/v4l2loopback/0.13.1/build/v4l2loopback.ko] undefined! make[3]: *** [/usr/src/linux-headers-6.7.12-common/scripts/Makefile.modpost:145: /var/lib/dkms/v4l2loopback/0.13.1/build/Module.symvers] Error 1 make[2]: *** [/usr/src/linux-headers-6.7.12-common/Makefile:1888: modpost] Error 2 make[1]: *** [/usr/src/linux-headers-6.7.12-common/Makefile:246: __sub-make] Error 2 make[1]: Leaving directory '/usr/src/linux-headers-6.7.12-686-pae' make: *** [Makefile:53: v4l2loopback.ko] Error 2 This probably affects more 32-bit architectures ... IIRC gcc generates a __moddi3 function call for (long long) a % (long long) b (or a similar operation on long long) on architectures without native support for long long. The symbol is provided by libgcc_s but for obvious reasons the kernel cannot be linked agaist that library. This seems to be a regression from the v4l2loopback-dkms + linux-headers-* combination in bookworm. This problem does not appear during the autopkgtest since that is restricted to amd64 and arm64 (which is probably a copy+paste mistake as the commit references bbswitch-dkms which is only useful on platforms with the proprietary nvidia driver and thus restricted to these architectures). Andreas