[PATCH] pmdomain: rockchip: fix domain check in rockchip_pm_add_one_domain()

[Shawn Lin]

在 2026/09/22 星期二 0:13, Sergey Shtylyov 写道:
> On 9/21/26 9:36 AM, Shawn Lin wrote:
> 
> [...]
> 
>>> In rockchip_pm_add_one_domain(), there's the check (most probably for
>>> the case where the "reg" prop has an unexpected value?) which doesn't
>>
>> Agreed that check indeed makes little sense. But "most probably for the
>> case where the reg prop has an unexpected value" does not hold: an
> 
>     I tried to guess what the check in question was actually intended for
> (despite making a little sense as it is now)...
> 
>> out-of-range reg value is already rejected by the "id >= pmu->info-
>>> num_domains" check above, and num_domains equals
> 
>     I noticed. :-)
> 
>> ARRAY_SIZE(domain_info) for every SoC, so there are no holes in the
>> table that the new check could catch with the current data. AFAICT, this
> 
>     Oh, there are holes! :-)
>     If you look at (and behind) the indexed initializers of *_pm_domains[],
> you'll see that the indexes don't always start at 0, and so the arrays are
> actually sparse...

Looked more closely by each one, you're right.

> 
>> patch does not change any runtime behaviour; it only turns dead code
>> into a defensive check on the match-data tables.
> 
>     I hope you see now that this defensive check makes a bit more sense...
> 
>>> make much sense as the variable pd_info will be NULL iff pmu->info->
>>> domain_info is NULL and the variable id is 0.  What does make sense
>>> there is checking pd_info->pwr_mask and pd_info->req_mask which (as
>>> seems to follow from the code) can't both be 0 for a valid domain...
>>
>> That means there is no bug being fixed here, should we drop the fixes tag?
> 
>     I'd like to keep it (but that's up to the maintainers, of course)...

Sure, it's  Ulf's call. Anyway, feel free to add

Reviewed-by: Shawn Lin <shawn.lin at rock-chips.com>

> 
>>> Found by Linux Verification Center (linuxtesting.org) with the Svace
>>> static analysis tool.
>>>
>>> Fixes: 7c696693a4f5 ("soc: rockchip: power-domain: Add power domain driver")
>>> Signed-off-by: Sergey Shtylyov <s.shtylyov at auroraos.dev>
> 
> [...]
> 
> MBR, Sergey
> 
>