Restart straight into Linux

A normal restart returns the PS5 to the PS5 OS, and you run the jailbreak and the loader again. A warm restart skips that: the running kernel loads the next one with kexec and jumps to it. Experimental: it works for many, and it has known hazards.

Credits: Dasloh (sleep and USB power fixes around it), the PS5 Bazzite Deck image for the units below.

How it works

The kernel's kexec_file_load system call takes the kernel, the initrd and the command line directly, so no kexec-tools package is needed. files/ps5-kexec is a short Python script that:

1. finds the boot partition (/efi, /boot/efi, or mounts LABEL=boot read-only),
2. reads cmdline.txt, opens bzImage and initrd.img, and calls kexec_file_load,
3. on exec, calls reboot(LINUX_REBOOT_CMD_KEXEC).

Because it reads the boot partition at restart time, a kernel you have just updated and the current cmdline.txt are always what boots next.

On a systemd system, the units around it:

Unit	Role
ps5-kexec-prepare.service	Runs ps5-kexec load. Pulled in by an overridden reboot.target before umount.target, so it runs for restarts only, never for power-off.
ps5-reboot.service	Required by reboot.target: runs systemctl --force kexec when a kernel is loaded and systemctl --force reboot otherwise.
/usr/sbin/kexec shim	systemd runs kexec -e at the very end; without kexec-tools the shim calls ps5-kexec exec.

Sources: files/ps5-kexec-prepare.service, files/ps5-reboot.service, files/kexec-shim. Confirmed on original PS5s and Slims.

What isn't reset

A warm restart starts the new kernel without the console's firmware resetting anything:

• The Wi-Fi/Bluetooth chip keeps whatever state the last boot left. The IW620's Wi-Fi usually needs repairing after a warm boot (the image reloads the driver when it finds a marker file from the previous boot). Its Bluetooth side can hang; reload btusb, or power off.
• The picture: the HDMI chip is not re-initialised by the loader. The new kernel sets the mode up again; a display that needs the full link-training sequence may stay black until a cold start.

IW620 hazard

With the Linux-only Bluetooth address on, a warm restart can leave the IW620 hung: Bluetooth gone, sometimes Wi-Fi too, until a power-off and a start with the loader. There is no fix yet. Don't use both at once on an IW620 console.

PS5 Bazzite Deck

ps5-warm-reboot on turns it on; while the Linux-only address is on, IW620 consoles get a normal restart instead. sudo reboot then restarts into Linux; ps5-reboot-to-ps5 restarts into the PS5 OS once.