Messages in this thread | | | Date | Thu, 23 Feb 2012 23:27:33 +0100 | From | Willy Tarreau <> | Subject | Re: [PATCH 0/5] i387: stable kernel backport |
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On Thu, Feb 23, 2012 at 02:11:48PM -0800, Linus Torvalds wrote: > On Thu, Feb 23, 2012 at 1:52 PM, Willy Tarreau <w@1wt.eu> wrote: > > > > I would test this too, but apart from ensuring my kernel still boots, > > how do I ensure the patches do really fix what the ought to fix ? I > > must admit I didn't catch the initial issue they were supposed to fix > > unfortunately :-/ > > Almost nobody did. > > This only happens on modern CPU's that support the new AES-NI > instructions, and only with a 32-bit kernel (although the very > unlikely preemption issues can happen on x86-64 too). And you need to > have the AES instructions called from interrupts, which probably only > happens with the mac80211 wireless networking stack. > > And even then you need WPA2 to trigger it (I guess AES is sometimes > used with "extended WPA1" too, but I dunno). > > So it's not impossible to trigger, but you do need to have a fairly > recent CPU that happily runs in 64-bit mode, and install a 32-bit > system on it. And it needs to use the right wireless setup.
OK so indeed I will only be able to check that it boots :-/
> It's possible that the right solution for really older kernels is just > to say that AES_NI depends on X86_64.
Might be a good idea !
Thanks for the explanation, Willy
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