linux-kernel - Re: [PATCH Part2 v6 13/49] crypto:ccp: Provide APIs to issue SEV-SNP commands

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAMkAt6pnqWWA8pc6uY5g1o076VLgjy1K1ZagDOgcuQfh=hnf3Q@mail.gmail.com>
Date:   Mon, 3 Oct 2022 12:01:19 -0600
From:   Peter Gonda <pgonda@...gle.com>
To:     Borislav Petkov <bp@...en8.de>
Cc:     "Kalra, Ashish" <Ashish.Kalra@....com>,
        "x86@...nel.org" <x86@...nel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "kvm@...r.kernel.org" <kvm@...r.kernel.org>,
        "linux-coco@...ts.linux.dev" <linux-coco@...ts.linux.dev>,
        "linux-mm@...ck.org" <linux-mm@...ck.org>,
        "linux-crypto@...r.kernel.org" <linux-crypto@...r.kernel.org>,
        "tglx@...utronix.de" <tglx@...utronix.de>,
        "mingo@...hat.com" <mingo@...hat.com>,
        "jroedel@...e.de" <jroedel@...e.de>,
        "Lendacky, Thomas" <Thomas.Lendacky@....com>,
        "hpa@...or.com" <hpa@...or.com>,
        "ardb@...nel.org" <ardb@...nel.org>,
        "pbonzini@...hat.com" <pbonzini@...hat.com>,
        "seanjc@...gle.com" <seanjc@...gle.com>,
        "vkuznets@...hat.com" <vkuznets@...hat.com>,
        "jmattson@...gle.com" <jmattson@...gle.com>,
        "luto@...nel.org" <luto@...nel.org>,
        "dave.hansen@...ux.intel.com" <dave.hansen@...ux.intel.com>,
        "slp@...hat.com" <slp@...hat.com>,
        "peterz@...radead.org" <peterz@...radead.org>,
        "srinivas.pandruvada@...ux.intel.com" 
        <srinivas.pandruvada@...ux.intel.com>,
        "rientjes@...gle.com" <rientjes@...gle.com>,
        "dovmurik@...ux.ibm.com" <dovmurik@...ux.ibm.com>,
        "tobin@....com" <tobin@....com>,
        "Roth, Michael" <Michael.Roth@....com>,
        "vbabka@...e.cz" <vbabka@...e.cz>,
        "kirill@...temov.name" <kirill@...temov.name>,
        "ak@...ux.intel.com" <ak@...ux.intel.com>,
        "tony.luck@...el.com" <tony.luck@...el.com>,
        "marcorr@...gle.com" <marcorr@...gle.com>,
        "sathyanarayanan.kuppuswamy@...ux.intel.com" 
        <sathyanarayanan.kuppuswamy@...ux.intel.com>,
        "alpergun@...gle.com" <alpergun@...gle.com>,
        "dgilbert@...hat.com" <dgilbert@...hat.com>,
        "jarkko@...nel.org" <jarkko@...nel.org>
Subject: Re: [PATCH Part2 v6 13/49] crypto:ccp: Provide APIs to issue SEV-SNP commands

On Mon, Oct 3, 2022 at 11:45 AM Borislav Petkov <bp@...en8.de> wrote:
>
> On Mon, Oct 03, 2022 at 05:11:05PM +0000, Kalra, Ashish wrote:
> > They are basically providing the APIs for the hypervisor to manage a
> > SNP guest.
>
> Yes, I know. But that is not my question. Lemme try again.
>
> My previous comment was:
>
> "I think you should simply export sev_do_cmd() and call it instead."
>
> In this case, the API is a single function - sev_do_cmd() - which the
> hypervisor calls.
>
> So my question still stands: why is it better to have silly wrappers
> of sev_do_cmd() instead of having the hypervisor call sev_do_cmd()
> directly?

We already have sev_issue_cmd_external_user() exported right?

Another option could be to make these wrappers more helpful and less
silly. For example callers need to know the PSP command format right
now, see  sev_guest_decommission().

int sev_guest_decommission(struct sev_data_decommission *data, int *error)

Instead of taking @data this function could just take inputs to create
sev_data_decommission:

int sev_guest_decommission(u32 handle, int *error)
>
> --
> Regards/Gruss,
>     Boris.
>
> https://people.kernel.org/tglx/notes-about-netiquette