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Date: Fri, 11 Aug 2017 14:54:42 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Juergen Gross <jgross@suse.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>,
        Jork Loeser <Jork.Loeser@microsoft.com>,
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Subject: Re: [tip:x86/platform] x86/hyper-v: Use hypercall for remote TLB
 flush
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On Fri, Aug 11, 2017 at 02:46:41PM +0200, Juergen Gross wrote:
> Aah, okay. Now I understand the problem. The TLB isn't the issue but the
> IPI is serving two purposes here: TLB flushing (which is allowed to
> happen at any time) and serialization regarding access to critical pages
> (which seems to be broken in the Xen case as you suggest).

Indeed, and now hyper-v as well.