The PREEMPT_RT kernel binary is now available in the rpi-update 'master' branch so its no longer necessary to specify the branch nameCode:
sudo WANT_64BIT_RT=1 rpi-update
The PREEMPT_RT kernel (6.12.33) from rpi-update now boots and runs from a USB device on a Raspberry Pi 3B+.
A PREEMPT_RT kernel (6.12.33) built locally using bcm2711_rt_defconfig also boots and runs from a USB device on a Raspberry Pi 3B+ now, but I do notice one oddity:
Code:
-rwxr-xr-x 1 root root 11991093 Jun 12 15:42 initramfs8.bak # PREEMPT_RT kernel from rpi-update-rwxr-xr-x 1 root root 7667311 Jun 12 15:45 initramfs8 # PREEMPT_RT kernel built locally using bcm2711_rt_defconfigIs this difference (4,323,782 bytes smaller initramfs) when built locally to be expected at this point?
PREEMPT kernels built locally using bcm2711_defconfig do not end up having a smaller than expected initramfs.
Statistics: Posted by RonR — Thu Jun 12, 2025 9:49 pm