From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andri Yngvason <andri.yngvason@marel.com>
Subject: Re: [PATCH v2 02/12] can: rx-offload: Add support for timestamp based irq
 offloading
Date: Mon, 4 Jul 2016 18:49:42 +0000
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Cc: david@protonic.nl, Marc Kleine-Budde <mkl@pengutronix.de>

Quoting Marc Kleine-Budde (2016-07-04 18:32:07)
> +static int can_rx_offload_compare(struct sk_buff *a, struct sk_buff *b)
> +{
> +       const struct can_rx_offload_cb *cb_a, *cb_b;
> +
> +       cb_a = can_rx_offload_get_cb(a);
> +       cb_b = can_rx_offload_get_cb(b);
> +
> +       return cb_b->timestamp - cb_a->timestamp;
> +}

Hi Marc,

An int is not large enough to store the difference between two u32.

E.g. INT_MAX - (-1) = INT_MIN

They're unlikely to be very far apart, but you can never be too cautious. ;)

See
http://stackoverflow.com/questions/10996418/efficient-integer-compare-function

Best regards,
Andri