linux-kernel - RE: [PATCH] x86/mm: Print the encryption features correctly when a paravisor is present

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: <SA1PR21MB1335B68B21B1F37ECC6D77F0BFDBA@SA1PR21MB1335.namprd21.prod.outlook.com>
Date:   Fri, 20 Oct 2023 20:00:13 +0000
From:   Dexuan Cui <decui@...rosoft.com>
To:     Dave Hansen <dave.hansen@...el.com>,
        KY Srinivasan <kys@...rosoft.com>,
        Haiyang Zhang <haiyangz@...rosoft.com>,
        "wei.liu@...nel.org" <wei.liu@...nel.org>,
        "tglx@...utronix.de" <tglx@...utronix.de>,
        "mingo@...hat.com" <mingo@...hat.com>,
        "bp@...en8.de" <bp@...en8.de>,
        "dave.hansen@...ux.intel.com" <dave.hansen@...ux.intel.com>,
        "x86@...nel.org" <x86@...nel.org>, "hpa@...or.com" <hpa@...or.com>,
        "luto@...nel.org" <luto@...nel.org>,
        "peterz@...radead.org" <peterz@...radead.org>,
        "stefan.bader@...onical.com" <stefan.bader@...onical.com>,
        Tim Gardner <tim.gardner@...onical.com>,
        "roxana.nicolescu@...onical.com" <roxana.nicolescu@...onical.com>,
        "cascardo@...onical.com" <cascardo@...onical.com>,
        "Michael Kelley (LINUX)" <mikelley@...rosoft.com>,
        "jgross@...e.com" <jgross@...e.com>,
        "sathyanarayanan.kuppuswamy@...ux.intel.com" 
        <sathyanarayanan.kuppuswamy@...ux.intel.com>,
        "kirill.shutemov@...ux.intel.com" <kirill.shutemov@...ux.intel.com>,
        "sashal@...nel.org" <sashal@...nel.org>,
        "matija.glavinic-pecotic.ext@...ia.com" 
        <matija.glavinic-pecotic.ext@...ia.com>,
        "linux-hyperv@...r.kernel.org" <linux-hyperv@...r.kernel.org>
CC:     "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: RE: [PATCH] x86/mm: Print the encryption features correctly when a
 paravisor is present

> From: Dave Hansen <dave.hansen@...el.com>
> Sent: Friday, October 20, 2023 11:40 AM
> To: Dexuan Cui <decui@...rosoft.com>; KY Srinivasan
> [...]
> On 10/19/23 23:01, Dexuan Cui wrote:
> > This patch only modifies x86 related files. I think it's unlikely to see
> > a third hardware Coco implementation for x86 in the foreseeable feature
> (?)
> 
> OK, then what good is this patch in the first place?  If you are right,
> then this would give equivalent information:
> 
> cat /proc/cpuinfo | grep -q Intel && echo 'TDX'
> cat /proc/cpuinfo | grep -q AMD   && echo 'SEV'
> 
> No kernel patching needed, right?

Currently arch/x86/mm/mem_encrypt.c: print_mem_encrypt_feature_info()
prints an incorrect and confusing message 
"Memory Encryption Features active: AMD SEV".
when an Intel TDX VM with a paravisor runs on Hyper-V.

So I think a kernel patch is needed.