linux-kernel - Re: [PATCH 2/4] x86/xor: improve XMM register spill/fill

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: <504DF3BC.30708@zytor.com>
Date:	Mon, 10 Sep 2012 07:05:48 -0700
From:	"H. Peter Anvin" <hpa@...or.com>
To:	Jan Beulich <JBeulich@...e.com>
CC:	mingo@...e.hu, tglx@...utronix.de, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 2/4] x86/xor: improve XMM register spill/fill

On 09/10/2012 05:38 AM, Jan Beulich wrote:
> +/*
> + * By forcing the alignment beyond the default of 16 bytes, we make the
> + * compiler guarantee the alignment. Passing -mincoming-stack-boundary=3
> + * (which would have been the better global alternative, as the kernel
> + * never guarantees better stack alignment) isn't permitted on x86-64.
> + */

The very latest gcc should handle it, and in fact we compile with 
-mstack-alignment=3 if gcc accepts it (if it is not yet upstream it will 
be soon.)  This affects the validity of this patch.

	-hpa

-- 
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.

--
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/