Re: [PATCH] ARM: integrator: Fix early initialization

[Guenter Roeck <linux@roeck-us.net>]

On 5/18/25 10:47, Russell King (Oracle) wrote:
> On Sun, May 18, 2025 at 09:41:18AM -0700, Guenter Roeck wrote:
>> Starting with commit bdb249fce9ad4 ("ARM: integrator: read counter using
>> syscon/regmap"), intcp_init_early calls syscon_regmap_lookup_by_compatible
>> which in turn calls of_syscon_register. This function allocates memory.
>> Since the memory management code has not been initialized at that time,
>> the call always fails. It either returns -ENOMEM or crashes as follows.
> 
> Yet I see no thought whether having the scheduler see sched_clock()
> suddenly change is a good idea or not. The point of the initialisation
> being early is to avoid a jump in the scheduler clock.
> 
> So, was the commit you're trying to fix a good idea after all?
> 
> That question at least needs to be considered, rather than just moving
> stuff like this later.
>

Absolutely. Just consider this to be a bug report with a proposed fix.

Thanks,
Guenter