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Date:   Fri, 25 Mar 2022 21:45:24 -0700
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To:     Borislav Petkov <bp@alien8.de>,
        Matthias Welwarsky <matthias.welwarsky@sysgo.com>,
        Dave Hansen <dave.hansen@linux.intel.com>
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References: <3422754.iIbC2pHGDl@linux-3513> <Yj49F1pnehy3ga5U@zn.tnic>
From:   Dave Hansen <dave.hansen@intel.com>
Subject: Re: x86, possible bug in __memmove() alternatives patching
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On 3/25/22 15:07, Borislav Petkov wrote:
> I know it's is probably a very rare case and Intel recommends having fast 
> string ops enabled, hence the question: would this be considered a bug in the 
> kernel that should be fixed? A potential fix could be to clear FSRM together 
> with ERMS depending on IA32_MISC_ENABLE.

I'd consider it a bug in the hypervisor, personally. ;)

But, we do try to make the kernel work even the face of funky
hypervisors that do things that never occur on real hardware.  If a nice
patch to fix this up showed up, I'd definitely take a look.