Re: [PATCH net-next v2] net: napi: Prevent overflow of napi_defer_hard_irqs

[Eric Dumazet]

On Wed, Sep 4, 2024 at 5:34 PM Joe Damato <jdamato@xxxxxxxxxx> wrote:
>
> In commit 6f8b12d661d0 ("net: napi: add hard irqs deferral feature")
> napi_defer_irqs was added to net_device and napi_defer_irqs_count was
> added to napi_struct, both as type int.
>
> This value never goes below zero, so there is not reason for it to be a
> signed int. Change the type for both from int to u32, and add an
> overflow check to sysfs to limit the value to S32_MAX.
>
> The limit of S32_MAX was chosen because the practical limit before this
> patch was S32_MAX (anything larger was an overflow) and thus there are
> no behavioral changes introduced. If the extra bit is needed in the
> future, the limit can be raised.

Reviewed-by: Eric Dumazet <edumazet@xxxxxxxxxx>