Re: (RPi) db> reboot -> cpu_reset failed

Hi Mitchell ,

`ve tested D37981 on a Pi4b, 
sorry but it had no effect,
not on the booted machine and not when intentionally provoked crashing in early boot up( no changed behavior in reset) .

I never see :
<<debug.kdb.enter: 0KDB: enter: sysctl debug.kdb.enter>>
(except, of course when entering directly by : sysctl debug.kdb.enter=1)

From the booted system( so you see that the new tunable is compiled in) :
—
root@:~ # sysctl debug.ddb.full_reboot=1
debug.ddb.full_reboot: 1 -> 1
root@:~ # root@:~ # sysctl debug.kdb.panic=1
….
KDB: enter: panic
[ thread pid 1056 tid 100128 ]
Stopped at      kdb_enter+0x44: undefined       f900827f
db> 
--

root@:~ # sysctl debug.ddb.full_reboot=0
debug.ddb.full_reboot: 1 -> 0
root@:~ # sysctl debug.kdb.panic=1
...
KDB: enter: panic
[ thread pid 1057 tid 100092 ]
Stopped at      kdb_enter+0x44: undefined       f900827f
db> 
—


but perhaps I have overlooked something

Regards

K.



> Am 08.01.2023 um 19:32 schrieb Mitchell Horne <mhorne@freebsd.org>:
> 
> …….
> 
> The reason for the difference in behaviour here is that the ddb reset command doesn't execute the full list of registered shutdown handlers, it just calls cpu_reset() directly. For whatever reason your combination of RPI hw+fw doesn't support the PSCI shutdown interface, so cpu_reset() fails. I am guessing that it is the bcm2835_watchdog driver that handles the normal reboot.
> 
> I think it should be just fine to execute such handlers from ddb reset, so you can try my patch: https://reviews.freebsd.org/D37981
> 
> Cheers,
> Mitchell
>