linux-kernel - Re: roundup_pow_of_two() may not handle 64-bit integers

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]

Date:	Thu, 15 May 2014 16:03:09 +0100
From:	David Howells <dhowells@...hat.com>
To:	Brian Norris <computersforpeace@...il.com>
Cc:	dhowells@...hat.com, Linux Kernel <linux-kernel@...r.kernel.org>,
	Benjamin Herrenschmidt <benh@...nel.crashing.org>,
	Paul Mackerras <paulus@...ba.org>,
	linuxppc-dev@...ts.ozlabs.org,
	Andrew Morton <akpm@...ux-foundation.org>
Subject: Re: roundup_pow_of_two() may not handle 64-bit integers

Brian Norris <computersforpeace@...il.com> wrote:

> I'm looking to use roundup_pow_of_two() (actually, order_base_2())
> from <linux/log2.h>, but it seems that it only supports 64-bit integers
> if your toolchain uses a 64-bit 'unsigned long' type. This is strange,
> considering that ilog2() is explicitly designed for 32-bit or 64-bit
> compatibility.

ilog2() was explicitly designed for use with 'unsigned long'.  See the commit
description (f0d1b0b30d250a07627ad8b9fbbb5c7cc08422e8).  It may work with
unsigned long long, however...

David


--
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/