I've made an update to the rpi 2 & 3 kernel source (armv7.s and rebootcode.s) which fixes a couple of long-standing flaws in the multicore startup:
- dependency on the order of object files for the 5l command in the mkfile, resulting in "lock loop" or "only 1 cpu started" error for some configurations - flakiness in /dev/reboot, making it unreliable except with *ncpu=1 It should now be possible consistently to reboot a pi in multicore mode from a named file using the 'reboot' or 'fshalt -r' command. This extends the possibilities for using the Plan 9 kernel itself as a boot loader (with an rc script as /boot/boot), eg to boot from an AoE server or over a wifi connection.
