Date:   Mon, 15 Nov 2021 17:36:41 +0100
From:   Joerg Roedel <jroedel@suse.de>
To:     Sean Christopherson <seanjc@google.com>
Cc:     Marc Orr <marcorr@google.com>, Peter Gonda <pgonda@google.com>,
        Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@intel.com>,
        Brijesh Singh <brijesh.singh@amd.com>, x86@kernel.org,
        linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
        linux-coco@lists.linux.dev, linux-mm@kvack.org,
        linux-crypto@vger.kernel.org, Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        Tom Lendacky <Thomas.Lendacky@amd.com>,
        "H. Peter Anvin" <hpa@zytor.com>, Ard Biesheuvel <ardb@kernel.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Andy Lutomirski <luto@kernel.org>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Sergio Lopez <slp@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>,
        David Rientjes <rientjes@google.com>,
        Dov Murik <dovmurik@linux.ibm.com>,
        Tobin Feldman-Fitzthum <tobin@ibm.com>,
        Michael Roth <Michael.Roth@amd.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        "Kirill A . Shutemov" <kirill@shutemov.name>,
        Andi Kleen <ak@linux.intel.com>, tony.luck@intel.com,
        sathyanarayanan.kuppuswamy@linux.intel.com
Subject: Re: [PATCH Part2 v5 00/45] Add AMD Secure Nested Paging (SEV-SNP)
 Hypervisor Support
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On Sat, Nov 13, 2021 at 06:34:52PM +0000, Sean Christopherson wrote:
> I'm not treating it nonchalantly, merely acknowledging that (a) some flavors of kernel
> bugs (or hardware issues!) are inherently fatal to the system, and (b) crashing the
> host may be preferable to continuing on in certain cases, e.g. if continuing on has a
> high probablity of corrupting guest data.

The problem here is that for SNP host-side RMP faults it will often not
be clear at fault-time if it was caused by wrong guest or host behavior. 

I agree with Marc that crashing the host is not the right thing to do in
this situation. Instead debug data should be collected to do further
post-mortem analysis.

Regards,

-- 
J?rg R?del
jroedel@suse.de

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