Re: [PATCH] net: dsa: sja1105: Remove unneeded cast in sja1105_crc32()

On Tue, Feb 23, 2021 at 12:20:03PM +0100, Geert Uytterhoeven wrote:

sja1105_unpack() takes a "const void *buf" as its first parameter, so
there is no need to cast away the "const" of the "buf" variable before
calling it.

Drop the cast, as it prevents the compiler performing some checks.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
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Reviewed-by: Vladimir Oltean <olteanv@gmail.com>

By the way, your email went straight to my spam box, I just found the
patch by mistake on patchwork.

    Why is this message in spam?
    It is in violation of Google's recommended email sender guidelines.

Compile-tested only.

BTW, sja1105_packing() and packing() are really bad APIs, as the input
pointer parameters cannot be const due to the direction depending on
"op".  This means the compiler cannot do const checks.  Worse, callers
are required to cast away constness to prevent the compiler from
issueing warnings.  Please don't do this!
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What const checks can the compiler not do?
Also, if you know of an existing kernel API which can replace packing(),
I'm all ears.