linux-kernel - RE: [PATCH] wifi: rt2x00: use explicitly signed type for clamping

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <0ca418f756a94859a6d32325c063f2a5@AcuMS.aculab.com>
Date:   Wed, 19 Oct 2022 08:01:13 +0000
From:   David Laight <David.Laight@...LAB.COM>
To:     'Andy Shevchenko' <andriy.shevchenko@...ux.intel.com>,
        "Jason A. Donenfeld" <Jason@...c4.com>
CC:     "linux-wireless@...r.kernel.org" <linux-wireless@...r.kernel.org>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Stanislaw Gruszka <stf_xl@...pl>,
        Helmut Schaa <helmut.schaa@...glemail.com>,
        Kalle Valo <kvalo@...nel.org>
Subject: RE: [PATCH] wifi: rt2x00: use explicitly signed type for clamping

From: Andy Shevchenko
> Sent: 18 October 2022 22:10
....
> It's not a hot path as far as I understand and keeping data types aligned seems
> to me worth it even if codegen is changed. IS it so awful with short?

(without looking at the generated code)
Why is it even short, what is wrong with int?
It is extremely unlikely that the code requires any
calculation results be masked to 8 (or 16) bits, but
using s8 or s16 requires the compiler emit code to mask
any calculated values.

Remember, all C arithmetic requires promoting the values
to (at least) int.

	David

-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)