linux-kernel - Re: PATCH] Use -mpreferred-stack-boundary=3 on x86-64 if supported

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: <20120623161324.GS11413@one.firstfloor.org>
Date:	Sat, 23 Jun 2012 18:13:24 +0200
From:	Andi Kleen <andi@...stfloor.org>
To:	"H.J. Lu" <hjl.tools@...il.com>
Cc:	LKML <linux-kernel@...r.kernel.org>,
	Andi Kleen <andi@...stfloor.org>,
	"H. Peter Anvin" <hpa@...or.com>
Subject: Re: PATCH] Use -mpreferred-stack-boundary=3 on x86-64 if supported

> This patch uses -mpreferred-stack-boundary=3 on x86-64 if it is supported.
> I have been running 3.4 kernel compiled with this option for weeks.

But why? 

All the SSE code in the kernel should adjust manually. And the other
code doesn't need it.

Besides the entry points do not guarantee alignment.

For the kernel it would be probably more useful to have a attribute
per function that forces alignment.

-Andi
-- 
ak@...ux.intel.com -- Speaking for myself only.
--
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/