linux-kernel - Re: [PATCH] bitmap_equal memcmp optimization for s390

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-next>] [day] [month] [year] [list]

Date:	Thu, 09 Jun 2016 15:26:47 +0100
From:	David Howells <dhowells@...hat.com>
To:	Martin Schwidefsky <schwidefsky@...ibm.com>
Cc:	dhowells@...hat.com, linux-arch@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	Benjamin Herrenschmidt <benh@...nel.crashing.org>,
	"David S. Miller" <davem@...emloft.net>
Subject: Re: [PATCH] bitmap_equal memcmp optimization for s390

Martin Schwidefsky <schwidefsky@...ibm.com> wrote:

> I hesitate to put another CONFIG_S390 into common code, alternatively
> __HAVE_ARCH_MEMCMP could be used. There are 7 architectures with the
> define: arc, arm64, blackfin, frv, powerpc, s390 and sparc.
> Of those I guess only powerpc, s390 and sparc will have configs with
> (NR_CPUS > BITS_PER_LONG). For (NR_CPUS <= BITS_PER_LONG) the xor
> optimization is used.

FRV doesn't have __HAVE_ARCH_MEMCMP for __KERNEL__.

David