kexec do not work on raspberrypi5

[montjoie]

Describe the bug

I want to kexec to a new/same kernel
Every kexec end after Bye! is displayed
Tryed 6.6.28-v8-16k

Steps to reproduce the behaviour

Boot any raspberrypi5 kernel
do:
kexec --force newkernelmage
or
kexec --force newkernelmage --dtb newdtb

Device (s)

Raspberry Pi 5

System

buildroot

Logs

[ 61.900120] psci: CPU1 killed (polled 0 ms)
[ 61.923074] psci: CPU2 killed (polled 0 ms)
[ 61.943075] psci: CPU3 killed (polled 0 ms)
[ 61.947542] Bye!

Additional context

No response

[montjoie]

The new kernel seems to start, since one berry appear on hdmi0 (nothing more), but nothing appear on serial.
I have also tried latest 6.6.60.