linux-kernel - Re: [PATCH RFC v7 14/64] x86/sev: Add the host SEV-SNP initialization support

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]

Date:   Wed, 11 Jan 2023 16:50:56 +0200
From:   Sabin Rapan <sabrapan@...zon.com>
To:     Michael Roth <michael.roth@....com>, <kvm@...r.kernel.org>
CC:     <linux-coco@...ts.linux.dev>, <linux-mm@...ck.org>,
        <linux-crypto@...r.kernel.org>, <x86@...nel.org>,
        <linux-kernel@...r.kernel.org>, <tglx@...utronix.de>,
        <mingo@...hat.com>, <jroedel@...e.de>, <thomas.lendacky@....com>,
        <hpa@...or.com>, <ardb@...nel.org>, <pbonzini@...hat.com>,
        <seanjc@...gle.com>, <vkuznets@...hat.com>,
        <wanpengli@...cent.com>, <jmattson@...gle.com>, <luto@...nel.org>,
        <dave.hansen@...ux.intel.com>, <slp@...hat.com>,
        <pgonda@...gle.com>, <peterz@...radead.org>,
        <srinivas.pandruvada@...ux.intel.com>, <rientjes@...gle.com>,
        <dovmurik@...ux.ibm.com>, <tobin@....com>, <bp@...en8.de>,
        <vbabka@...e.cz>, <kirill@...temov.name>, <ak@...ux.intel.com>,
        <tony.luck@...el.com>, <marcorr@...gle.com>,
        <sathyanarayanan.kuppuswamy@...ux.intel.com>,
        <alpergun@...gle.com>, <dgilbert@...hat.com>, <jarkko@...nel.org>,
        <ashish.kalra@....com>, <harald@...fian.com>,
        Brijesh Singh <brijesh.singh@....com>
Subject: Re: [PATCH RFC v7 14/64] x86/sev: Add the host SEV-SNP initialization
 support



On 14.12.2022 21:40, Michael Roth wrote:
> +#ifdef CONFIG_AMD_MEM_ENCRYPT
> +# define DISABLE_SEV_SNP       0
> +#else
> +# define DISABLE_SEV_SNP       (1 << (X86_FEATURE_SEV_SNP & 31))
> +#endif
> +

Would it make sense to split the SEV-* feature family into their own
config flag(s) ?
I'm thinking in the context of SEV-SNP running on systems with
Transparent SME enabled in the bios. In this case, enabling
CONFIG_AMD_MEM_ENCRYPT will also enable SME in the kernel, which is a
bit strange and not necessarily useful.
Commit 4e2c87949f2b ("crypto: ccp - When TSME and SME both detected
notify user") highlights it.

--
Sabin.



Amazon Development Center (Romania) S.R.L. registered office: 27A Sf. Lazar Street, UBC5, floor 2, Iasi, Iasi County, 700045, Romania. Registered in Romania. Registration number J22/2621/2005.