From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linutronix.de (146.0.238.70:993) by crypto-ml.lab.linutronix.de with IMAP4-SSL for ; 19 Feb 2019 14:18:09 -0000 Received: from mail.kernel.org ([198.145.29.99]) by Galois.linutronix.de with esmtps (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1gw6Dn-0005yO-Bs for speck@linutronix.de; Tue, 19 Feb 2019 15:18:08 +0100 Date: Tue, 19 Feb 2019 15:17:58 +0100 From: Greg KH Subject: [MODERATED] Re: [patch 8/8] MDS basics 8 Message-ID: <20190219141758.GA17033@kroah.com> References: <20190219124406.449727187@linutronix.de> <20190219125346.509128952@linutronix.de> MIME-Version: 1.0 In-Reply-To: <20190219125346.509128952@linutronix.de> Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit To: speck@linutronix.de List-ID: On Tue, Feb 19, 2019 at 01:44:14PM +0100, speck for Thomas Gleixner wrote: > +Mitigation control on the kernel command line > +--------------------------------------------- > + > +The kernel command line allows to control the MDS mitigations at boot > +time with the option "mds=". The valid arguments for this option are: > + > + ============ ============================================================= > + full Provides all available mitigations for the MDS vulnerability > + vulnerability, unconditional CPU buffer clearing on exit to > + userspace and when entering a VM. > + > + It does not automatically disable SMT. > + > + off Disables MDS mitigations completely. > + > + ============ ============================================================= > + > +The default is 'full'. For details see :ref:`cpu_buffer_clear_full`. I think default is 'auto' according to the patch that enabled it :) thanks, greg k-h