Re: [PATCH RESEND] PM: domains: Fix return value of API dev_pm_get_subsys_data()

From: Greg Kroah-Hartman
Date: Tue Nov 12 2024 - 06:46:45 EST


On Mon, Oct 28, 2024 at 08:31:11PM +0800, Zijun Hu wrote:
> From: Zijun Hu <quic_zijuhu@xxxxxxxxxxx>
>
> dev_pm_get_subsys_data() has below 2 issues under condition
> (@dev->power.subsys_data != NULL):
>
> - it will do unnecessary kzalloc() and kfree().

But that's ok, everything still works, right?

> - it will return -ENOMEM if the kzalloc() fails, that is wrong
> since the kzalloc() is not needed.

But it's ok to return the proper error if the system is that broken.

>
> Fixed by not doing kzalloc() and returning 0 for the condition.
>
> Fixes: ef27bed1870d ("PM: Reference counting of power.subsys_data")
> Cc: stable@xxxxxxxxxxxxxxx

Why is this relevant for stable kernels?

thanks,

greg k-h