From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joerg Roedel <jroedel@suse.de>
Subject: Re: [PATCH v4 00/75] x86: SEV-ES Guest Support
Date: Wed, 15 Jul 2020 12:10:34 +0200
Message-ID: <20200715101034.GM16200@suse.de>
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To: Peter Zijlstra <peterz@infradead.org>
Cc: Joerg Roedel <joro@8bytes.org>, x86@kernel.org, hpa@zytor.com, Andy Lutomirski <luto@kernel.org>, Dave Hansen <dave.hansen@linux.intel.com>, Jiri Slaby <jslaby@suse.cz>, Dan Williams <dan.j.williams@intel.com>, Tom Lendacky <thomas.lendacky@amd.com>, Juergen Gross <jgross@suse.com>, Kees Cook <keescook@chromium.org>, David Rientjes <rientjes@google.com>, Cfir Cohen <cfir@google.com>, Erdem Aktas <erdemaktas@google.com>, Masami Hiramatsu <mhiramat@kernel.org>, Mike Stunes <mstunes@vmware.com>, Sean Christopherson <sean.j.christopherson@intel.com>, Martin Radev <martin.b.radev@gmail.com>, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org
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On Wed, Jul 15, 2020 at 11:55:56AM +0200, Peter Zijlstra wrote:
> And recursive #VC was instant death, right? Because there's no way to
> avoid IST stack corruption in that case.

Right, a #VC exception while still on the IST stack must instantly kill
the VM. That needs an additional check which is not implemented yet, as
it only becomes necessary with SNP.

Regards,

	Joerg