mold

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Fedora 36, mold 1,4,2, trying to build nvidia kernel modules (I have akmod-nvidia-515.76-1.fc36.x86_64 installed from fedora-multimedia repo) I get:

akmodsbuild: LD [M]  /tmp/akmodsbuild.SOF7B9wS/BUILD/nvidia-kmod-515.76-x86_64/_kmod_build_5.19.11-200.fc36.x86_64/nvidia-peermem.o
akmodsbuild: LD [M]  /tmp/akmodsbuild.SOF7B9wS/BUILD/nvidia-kmod-515.76-x86_64/_kmod_build_5.19.11-200.fc36.x86_64/nvidia-drm.o
akmodsbuild: MODPOST /tmp/akmodsbuild.SOF7B9wS/BUILD/nvidia-kmod-515.76-x86_64/_kmod_build_5.19.11-200.fc36.x86_64/Module.symvers
akmodsbuild: ERROR: modpost: missing MODULE_LICENSE() in /tmp/akmodsbuild.SOF7B9wS/BUILD/nvidia-kmod-515.76-x86_64/_kmod_build_5.19.11-200.fc36.x86_64/nvidia.o
akmodsbuild: ERROR: modpost: missing MODULE_LICENSE() in /tmp/akmodsbuild.SOF7B9wS/BUILD/nvidia-kmod-515.76-x86_64/_kmod_build_5.19.11-200.fc36.x86_64/nvidia-uvm.o
akmodsbuild: make[2]: *** [scripts/Makefile.modpost:128: /tmp/akmodsbuild.SOF7B9wS/BUILD/nvidia-kmod-515.76-x86_64/_kmod_build_5.19.11-200.fc36.x86_64/Module.symvers] Error 1

Switching to /usr/bin/ld.bfd fixes error. The same problem is described in https://forums.developer.nvidia.com/t/error-modpost-missing-module-license-in-tmp-akmodsbuild-qbwum82l-build-nvidia-kmod-515-65-01-kmod-build-5-19-9-300-fc37-x86-64-nvidia-o/228489

I believe Linux does something tricky with kernel modules, so I don't think mold can build them. We probably should show a warning message that that's not a supported use at the moment.

If only MODULE_LICENSE() is missing maybe it is not very difficult to support it?

If it's the only issue, it might not be too difficult to fix, but I'm not sure about the assumption.

You are probably right, just read about how lld (clang linker) started to support linking Linux kernel. Although here we are talking about modules, not the kernel itself, so it might be easier.