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Peter Anvin" , Ard Biesheuvel , Paolo Bonzini , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Andy Lutomirski , Dave Hansen , Sergio Lopez , Peter Gonda , Peter Zijlstra , Srinivas Pandruvada , David Rientjes , tony.luck@intel.com, npmccallum@redhat.com Subject: Re: [PATCH Part1 RFC v3 11/22] x86/sev: Add helper for validating pages in early enc attribute changes Message-ID: References: <20210602140416.23573-1-brijesh.singh@amd.com> <20210602140416.23573-12-brijesh.singh@amd.com> <70db789d-b1aa-c355-2d16-51ace4666b3f@amd.com> <9f012bcb-4756-600d-6fe8-b1db9b972f17@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <9f012bcb-4756-600d-6fe8-b1db9b972f17@amd.com> Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org On Wed, Jun 16, 2021 at 07:49:25AM -0500, Brijesh Singh wrote: > If you still think ... I think you should answer my question first: > Imagine you're a guest owner and you haven't written the SNP code and > you don't know how it works. > > You start a guest in the public cloud and it fails because the > hypervisor violates the GHCB protocol and all that guest prints before > it dies is > > "general request termination" > > How are you - the guest owner - going to find out what exactly happened? > > Call support? And let me paraphrase it again: if the error condition with which the guest terminates is not uniquely identifiable but simply a "general request", how are such conditions going to be debugged? -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette