Ok tried what you suggested and the /boot/firmware/6.12.47-custom/initramfs_2712 did NOT load for the default "factory" kernel.
I can confirm this, as when the initramfs file does load successfully (from /boot/firmware), dmesg will show:
[ 0.518942] Freeing initrd memory: 17920K
I can also confirm that the default kernel got loaded from the /boot/firmware/6.12.47-custom directory as I placed a cmdline.txt file in that directory with the dummy option, "mytesting=yes", and cat /proc/cmdline shows my dummy option to be set.
With the default kernel loaded in the 6.12.47-custom, uname -a shows:
Linux rpi-nvme 6.12.47+rpt-rpi-2712 #1 SMP PREEMPT Debian 1:6.12.47-1+rpt1 (2025-09-16) aarch64 GNU/Linux
I can confirm this, as when the initramfs file does load successfully (from /boot/firmware), dmesg will show:
[ 0.518942] Freeing initrd memory: 17920K
I can also confirm that the default kernel got loaded from the /boot/firmware/6.12.47-custom directory as I placed a cmdline.txt file in that directory with the dummy option, "mytesting=yes", and cat /proc/cmdline shows my dummy option to be set.
With the default kernel loaded in the 6.12.47-custom, uname -a shows:
Linux rpi-nvme 6.12.47+rpt-rpi-2712 #1 SMP PREEMPT Debian 1:6.12.47-1+rpt1 (2025-09-16) aarch64 GNU/Linux
Statistics: Posted by bitbasher — Mon Dec 01, 2025 8:25 pm