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Date:   Thu, 19 Mar 2020 20:38:13 +0100
From:   Joerg Roedel <jroedel@suse.de>
To:     Andy Lutomirski <luto@kernel.org>
Cc:     Joerg Roedel <joro@8bytes.org>, X86 ML <x86@kernel.org>,
        "H. Peter Anvin" <hpa@zytor.com>,
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Subject: Re: [PATCH 41/70] x86/sev-es: Add Runtime #VC Exception Handler
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References: <20200319091407.1481-1-joro@8bytes.org>
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On Thu, Mar 19, 2020 at 11:43:20AM -0700, Andy Lutomirski wrote:
> Or future generations could have enough hardware support for debugging
> that #DB doesn't need to be intercepted or can be re-injected
> correctly with the #DB vector.

Yeah, the problem is, the GHCB spec suggests the single-step-over-iret
way to re-enable the NMI window and requires intercepting #DB for it. So
the hypervisor probably still has to intercept it, even when debug
support is added some day. I need to think more about this.

Regards,

	Joerg