While working on a `dpkg` upload for Debian LTS bullseye, I noticed that the autopkgtests fail. Cf.: - workload: https://debusine.debian.net/debian/developers/work-request/911106 - autopkgtest logs: https://debusine.debian.net/debian/developers/artifact/4117393/ The test `test-func-root` fails with the following error: ``` 128s /usr/bin/make -C t-unpack-hardlink test 128s make[1]: Entering directory '/tmp/autopkgtest.Dq43vZ/build.UL0/src/tests/t-unpack-hardlink' 128s env PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin DPKG_DEBUG=1 mknod pkg-hardlink/test-null-link0 c 1 3 128s mknod: pkg-hardlink/test-null-link0: Operation not permitted 128s make[1]: *** [Makefile:20: pkg-hardlink/test-null-link0] Error 1 128s make[1]: Leaving directory '/tmp/autopkgtest.Dq43vZ/build.UL0/src/tests/t-unpack-hardlink' ``` This test has the `needs-root` restriction, and it succeeds on ci.debian.net, so I think the issue here is caused by the incus container. I guess by default the filesystem is mounted with `nodev` so `mknod` fails, or something like that. A quick google search suggests the argument `security.syscalls.intercept.mknod=true` for `incus launch`, FWIW.