MFC r367072:
Mount devfs inside a beinstall(8) chroot
It turns out that without /dev/null beinstall is not able to complete and
instead exits with messages similar to these:
>>> Installing kernel GENERIC completed on Sun Oct 25 17:47:37 CET 2020 -------------------------------------------------------------- /tmp/beinstall.JleGoP/mnt: Inspecting dirs /usr/src /usr/obj/usr/src/amd64.amd64 --- installworld --- make[1]: "/usr/obj/usr/src/amd64.amd64/toolchain-metadata.mk" line 1: Using cached toolchain metadata from build at t480 on Sun Oct 25 15:53:28 CET 2020 make[2]: "/dev/null" line 2: Need an operator make[2]: Fatal errors encountered -- cannot continuemake[1]: "/usr/src/Makefile.inc1" line 593: CPUTYPE global should be set with ?=. Cleaning up ... umount -f /tmp/beinstall.JleGoP/mnt/usr/src /tmp/beinstall.JleGoP/mnt/usr/obj/usr/src/amd64.amd64 /tmp/beinstall.JleGoP/mnt Destroyed successfully error: Installworld failed!
Upon a bit of debugging, it turns out that /dev/null inside the chroot
environment is full random bytes, which cause "make -f /dev/null" to
misbehave. Mounting a proper devfs inside the chroot seems to be the most
appropriate way to fix it.
will@ also noted that this change requires that whatever is needed in devfs
must exist in the old kernel.
Approved by: will