Re: [RFC PATCH 2/2] arm64: Use SYSTEM_OFF2 PSCI call to power off for hibernate

From: David Woodhouse
Date: Thu Mar 14 2024 - 07:27:46 EST


On 14 March 2024 12:09:11 CET, Sudeep Holla <sudeep.holla@xxxxxxx> wrote:
>On Wed, Mar 13, 2024 at 03:34:44PM +0000, Sudeep Holla wrote:
>> On Tue, Mar 12, 2024 at 04:36:05PM +0000, David Woodhouse wrote:
>> > On Tue, 2024-03-12 at 15:57 +0000, Sudeep Holla wrote:
>> > > Looked briefly at register_sys_off_handler and it should be OK to call
>> > > it from psci_init_system_off2() below. Any particular reason for having
>> > > separate initcall to do this ? We can even eliminate the need for
>> > > psci_init_system_off2 if it can be called from there. What am I missing ?
>> >
>> > My first attempt did that. I don't think we can kmalloc that early:
>> >
>>
>> That was was initial guess. But a quick hack on my setup and running it on
>> the FVP model didn't complain. I think either I messed up or something else
>> wrong, I must check on some h/w. Anyways sorry for the noise and thanks for
>> the response.
>>
>
>OK, it was indeed giving -ENOMEM which in my hack didn't get propogated
>properly 🙁. I assume you have some configs that is resulting in the
>crash instead of -ENOMEM as I see in my setup(FVP as well as hardware).
>
>Sorry for the noise.

Fairly stock Fedora config, with a few tweaks.
http://david.woodhou.se/arm-hibernate-config

I note kmalloc_trace() is in the backtrace.