linux-kernel - Re: [KERNEL]: Avoid divide in IS

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] [day] [month] [year] [list]

Message-ID: <jefxyzlo1g.fsf@sykes.suse.de>
Date:	Wed, 21 Nov 2007 14:35:07 +0100
From:	Andreas Schwab <schwab@...e.de>
To:	"linux-os (Dick Johnson)" <linux-os@...logic.com>
Cc:	"Herbert Xu" <herbert@...dor.apana.org.au>,
	"Linus Torvalds" <torvalds@...ux-foundation.org>,
	"Andrew Morton" <akpm@...ux-foundation.org>,
	"Linux Kernel Mailing List" <linux-kernel@...r.kernel.org>
Subject: Re: [KERNEL]: Avoid divide in IS_ALIGN

"linux-os (Dick Johnson)" <linux-os@...logic.com> writes:

> Executing this script.............
>
> cat <<EOF >/tmp/xxx.c
> #include <stdio.h>
>
> #define IS_ALIGNED(x,a)		(((x) % ((typeof(x))(a))) == 0)
> #define _IS_ALIGNED(x, a)	(((x) & ((typeof(x))(a) - 1)) == 0)
>
> int main()
> {
>     int i;
>     long p = 0x12345678;
>     for(i=1; i< 0x11; i++)
>         printf("Old = %d, new = %d\n", IS_ALIGNED(p, i), _IS_ALIGNED(p, i));

Alignment is only defined for powers of two.

Andreas.

-- 
Andreas Schwab, SuSE Labs, schwab@...e.de
SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
PGP key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/