linux-kernel - Re: [PATCH] x86/CPU/AMD: Clear RDRAND CPUID bit on AMD family 15h/16h

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: <alpine.DEB.2.21.1908152212120.1908@nanos.tec.linutronix.de>
Date:   Thu, 15 Aug 2019 22:14:48 +0200 (CEST)
From:   Thomas Gleixner <tglx@...utronix.de>
To:     Borislav Petkov <bp@...en8.de>
cc:     "Lendacky, Thomas" <Thomas.Lendacky@....com>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "linux-doc@...r.kernel.org" <linux-doc@...r.kernel.org>,
        "linux-pm@...r.kernel.org" <linux-pm@...r.kernel.org>,
        "x86@...nel.org" <x86@...nel.org>, Ingo Molnar <mingo@...hat.com>,
        "Rafael J . Wysocki" <rjw@...ysocki.net>,
        Pavel Machek <pavel@....cz>, Chen Yu <yu.c.chen@...el.com>,
        Jonathan Corbet <corbet@....net>
Subject: Re: [PATCH] x86/CPU/AMD: Clear RDRAND CPUID bit on AMD family
 15h/16h

On Thu, 15 Aug 2019, Borislav Petkov wrote:
> On Thu, Aug 15, 2019 at 01:47:24PM +0000, Lendacky, Thomas wrote:
> > I think this is a clearer indication that the action has taken place.
> 
> Yeah, but what does that bring us? You wanna know this now, while
> testing. Once that whole effort is done, it is a useless printing of
> info which you have in cpuinfo already.

No. Print something useful in dmesg, telling the user that and also why
this has been disabled.

That avoids stupid questions and if they come up nevertheless we can reduce
the answer to LMGT4Y.

Thanks,

	tglx