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Date:   Tue, 12 Apr 2022 08:54:10 -0700
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To:     Jon Kohler <jon@nutanix.com>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
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        Pawan Gupta <pawan.kumar.gupta@linux.intel.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Borislav Petkov <bp@suse.de>,
        Neelima Krishnan <neelima.krishnan@intel.com>,
        "kvm @ vger . kernel . org" <kvm@vger.kernel.org>
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From:   Dave Hansen <dave.hansen@intel.com>
Subject: Re: [PATCH] x86/tsx: fix KVM guest live migration for tsx=on
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On 4/12/22 06:36, Jon Kohler wrote:
> So my theory here is to extend the logical effort of the microcode driven
> automatic disablement as well as the tsx=auto automatic disablement and
> have tsx=on force abort all transactions on X86_BUG_TAA SKUs, but leave
> the CPU features enumerated to maintain live migration.
> 
> This would still leave TSX totally good on Ice Lake / non-buggy systems.
> 
> If it would help, I'm working up an RFC patch, and we could discuss there?

Sure.  But, it sounds like you really want a new tdx=something rather
than to muck with tsx=on behavior.  Surely someone else will come along
and complain that we broke their TDX setup if we change its behavior.

Maybe you should just pay the one-time cost and move your whole fleet
over to tsx=off if you truly believe nobody is using it.