Comment 5 for bug 1828084

amd64 counts as x86 for the purposes of supported architectures in Linux, and x86 does have the C version of recordmcount. Comment #3 includes a list of architectures that lack the C version of recordmcount. Of those architectures, ppc64le is the only one that is supported by the NVIDIA driver (the test case described in the reproduction steps). I did try to create a reproduction case independent of the NVIDIA driver, but was unsuccessful, as simpler kernel modules failed to cause a panic, and I hadn't isolated what specific behavior of the NVIDIA driver is problematic when recordmcount fails to run.

One troubleshooting technique you can use to verify whether recordmcount.pl is working when localization options are set is to instrument the Kbuild makefiles to record a checksum of the object file recordmcount is run against before running recordmcount and again after it has run. If recordmcount fails to run the checksums will be the same. Note that this is only useful on architectures which use recordmcount.pl rather than the C version, as the C version has no dependency on parsing the output of objdump.