Re: [PATCH net-next v2] af_unix: Fix undefined 'other' error

From: Simon Horman
Date: Tue Feb 18 2025 - 08:21:41 EST


On Mon, Feb 17, 2025 at 05:14:14PM +0300, Dan Carpenter wrote:
> On Mon, Feb 17, 2025 at 11:15:15AM +0000, Simon Horman wrote:
> > So, hypothetically, Smatch could be enhanced and there wouldn't be any
> > locking warnings with this patch applied?
>
> Heh. No. What I meant to say was that none of this has anything to do
> with Smatch. This is all Sparse stuff. But also I see now that my email
> was wrong...
>
> What happened is that we changed unix_sk() and that meant Sparse couldn't
> parse the annotations and prints "error: undefined identifier 'other'".
> The error disables Sparse checking for the file.
>
> When we fix the error then the checking is enabled again. The v1 patch
> which changes the annotation is better than the v2 patch because then
> it's 9 warnings vs 11 warnings.
>
> The warnings are all false positives. All old warnings are false
> positives. And again, these are all Sparse warnings, not Smatch. Smatch
> doesn't care about annotations. Smatch has different bugs completely.
> ;)

Thanks for clarifying :)

Based on the above I'd advocate accepting the code changes in v2 [*].
And live with the warnings.

Which I think is to say that Iwashima-san was right all along.

Reviewed-by: Simon Horman <horms@xxxxxxxxxx>

[*] Purva, please post a v3 that updates the commit message as per
Jakub's request elsewhere in this thread:
https://lore.kernel.org/all/20250212104845.2396abcf@xxxxxxxxxx/