From: "H. Peter Anvin" <hpa@zytor.com>
To: Willy Tarreau <w@1wt.eu>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org, Raphael Prevost <raphael@buro.asia>,
Suresh Siddha <suresh.b.siddha@intel.com>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 0/5] i387: stable kernel backport
Date: Thu, 23 Feb 2012 14:55:11 -0800 [thread overview]
Message-ID: <4F46C3CF.40303@zytor.com> (raw)
In-Reply-To: <20120223225227.GD1306@1wt.eu>
On 02/23/2012 02:52 PM, Willy Tarreau wrote:
> On Thu, Feb 23, 2012 at 02:48:51PM -0800, H. Peter Anvin wrote:
>> On 02/23/2012 02:38 PM, Linus Torvalds wrote:
>>>
>>> You'd still need an x86-32 machine to test on, because x86-64 was
>>> immune to this issue.
>>>
>>> But yeah, the impact of this seems to be small enough that for older
>>> kernels (which are likely used on older systems for maintenance
>>> anyway) disabling AES-NI on x86-32 really might be the way to go.
>>>
>>
>> That would really suck for users of encrypted hard disks.
>
> Peter, do you really think there are that many ? I think I only saw
> AES-NI on recent 64-bit capable chips, and it's been a while that
> users have been installing 64-bit distros on such machines. Note that
> I'm not advocating for breaking existing setups, just that I'm surprized
> by this combination (aes-ni + 32-bit).
>
There are still people running 32-bit systems because they have some odd
compatibility constraints but now have to deal with corporate or other
security constraints; they may also have been using disk encryption
since before AES-NI was in but doing it on the integer side is way slower.
This is not AES-NI in the interrupt path, but I don't think there is a
knob for that.
-hpa
--
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel. I don't speak on their behalf.
next prev parent reply other threads:[~2012-02-23 22:55 UTC|newest]
Thread overview: 50+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-02-22 20:54 [PATCH 0/5] i387: stable kernel backport Linus Torvalds
2012-02-22 20:56 ` [PATCH 1/5] i387: math_state_restore() isn't called from asm Linus Torvalds
2012-02-22 20:56 ` [PATCH 2/5] i387: make irq_fpu_usable() tests more robust Linus Torvalds
2012-02-22 20:57 ` [PATCH 3/5] i387: fix x86-64 preemption-unsafe user stack save/restore Linus Torvalds
2012-02-22 20:58 ` [PATCH 4/5] i387: move TS_USEDFPU clearing out of __save_init_fpu and into callers Linus Torvalds
2012-02-22 20:59 ` [PATCH 5/5] i387: move TS_USEDFPU flag from thread_info to task_struct Linus Torvalds
2012-02-22 21:02 ` [PATCH 0/5] i387: stable kernel backport H. Peter Anvin
2012-02-22 21:19 ` Greg Kroah-Hartman
2012-02-22 21:29 ` Linus Torvalds
2012-02-22 21:30 ` Linus Torvalds
2012-02-22 21:32 ` Greg Kroah-Hartman
2012-02-23 20:09 ` Greg Kroah-Hartman
2012-02-23 20:29 ` H. Peter Anvin
2012-02-23 20:48 ` Greg Kroah-Hartman
2012-02-23 20:51 ` H. Peter Anvin
2012-02-23 21:10 ` Greg Kroah-Hartman
2012-02-23 21:52 ` Willy Tarreau
2012-02-23 22:11 ` Linus Torvalds
2012-02-23 22:27 ` Willy Tarreau
2012-02-23 22:38 ` Linus Torvalds
2012-02-23 22:48 ` H. Peter Anvin
2012-02-23 22:52 ` Willy Tarreau
2012-02-23 22:55 ` H. Peter Anvin [this message]
2012-02-23 23:04 ` Willy Tarreau
2012-02-23 22:49 ` Willy Tarreau
2012-02-23 22:59 ` Greg Kroah-Hartman
2012-02-23 23:05 ` H. Peter Anvin
2012-02-23 23:16 ` Greg Kroah-Hartman
2012-02-23 23:18 ` H. Peter Anvin
2012-02-23 23:19 ` Suresh Siddha
2012-02-23 23:54 ` Greg Kroah-Hartman
2012-02-23 23:59 ` H. Peter Anvin
2012-02-24 0:47 ` H. Peter Anvin
2012-02-22 22:34 ` H. Peter Anvin
2012-02-22 22:45 ` H. Peter Anvin
2012-02-22 23:15 ` Linus Torvalds
2012-02-22 23:31 ` Linus Torvalds
2012-02-23 0:14 ` H. Peter Anvin
2012-02-23 0:25 ` Linus Torvalds
2012-02-23 0:37 ` Greg Kroah-Hartman
2012-02-23 1:47 ` raphael
2012-02-23 2:55 ` Linus Torvalds
2012-02-23 2:41 ` raphael
2012-02-23 3:37 ` Linus Torvalds
2012-02-23 18:15 ` Greg Kroah-Hartman
2012-02-23 19:36 ` Greg Kroah-Hartman
2012-02-23 19:41 ` Linus Torvalds
2012-02-23 19:50 ` Greg Kroah-Hartman
2012-02-23 19:55 ` Greg Kroah-Hartman
2012-02-23 20:02 ` Greg Kroah-Hartman
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