Messages in this thread | | | Date | Thu, 23 Feb 2012 14:55:11 -0800 | From | "H. Peter Anvin" <> | Subject | Re: [PATCH 0/5] i387: stable kernel backport |
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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.
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