Re: [PATCH v4] mm: cma: support sysfs

[Dmitry Osipenko]

19.03.2021 18:50, Greg Kroah-Hartman пишет:
>> Then initialization order won't be a problem.
> I don't understand the problem here, what is wrong with the patch as-is?

The cma->stat is NULL at the time when CMA is used on ARM because
cma->stat is initialized at the subsys level. This is the problem,
apparently.

> Also, watch out, if you only make the kobject dynamic, how are you going
> to get backwards from the kobject to the values you want to send to
> userspace in the show functions?

Still there should be a wrapper around the kobj with a back reference to
the cma entry. If you're suggesting that I should write a patch, then I
may take a look at it later on. Although, I assume that Minchan could
just correct this patch and re-push it to -next.