RE: [PATCH] drm/drm_vblank.c: avoid unsigned int to signed int cast

From: David Laight
Date: Tue May 23 2023 - 04:50:57 EST


From: 15330273260@xxxxxx <15330273260@xxxxxx>
> Sent: 23 May 2023 05:27
>
> On 2023/5/22 19:29, Jani Nikula wrote:
> > In general, do not use unsigned types in arithmethic to avoid negative
> > values, because most people will be tripped over by integer promotion
> > rules, and you'll get negative values anyway.
>
>
> Here I'm sure about this,
>
> but there are plenty unsigned types arithmetic in the kernel.

The real problem is (attempted) arithmetic on types smaller than int.
Regardless of whether they are signed or unsigned.

David

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