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 ; 12 Dec 2018 21:28:37 -0000 Received: from mga06.intel.com ([134.134.136.31]) by Galois.linutronix.de with esmtps (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1gXC3X-0001WY-NZ for speck@linutronix.de; Wed, 12 Dec 2018 22:28:36 +0100 Date: Wed, 12 Dec 2018 13:28:31 -0800 From: Andi Kleen Subject: [MODERATED] Re: [PATCH v2 1/8] MDSv2 4 Message-ID: <20181212212831.GH25620@tassilo.jf.intel.com> References: <20181212212246.GP9077@char.us.oracle.com> MIME-Version: 1.0 In-Reply-To: <20181212212246.GP9077@char.us.oracle.com> Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit To: speck@linutronix.de List-ID: On Wed, Dec 12, 2018 at 04:22:46PM -0500, speck for Konrad Rzeszutek Wilk wrote: > On Mon, Dec 10, 2018 at 09:53:33AM -0800, speck for Andi Kleen wrote: > > From: Andi Kleen > > Subject: x86/speculation/mds: Add basic bug infrastructure for > > MDS > > > > MDS is micro architectural data sampling, which is a side channel > > attack on internal buffers in Intel CPUs. They all have > > the same mitigations for single thread, so we lump them all > > together as a single MDS issue. > > > > This patch adds the basic infrastructure to detect if the current > > CPU is affected by MDS, and if yes set the right BUG bits. > > > > We also provide a command line option "mds_disable" to disable > > any workarounds. > > Would it be worth referencing a not-yet-posted Intel doc, > or at least point to the kernel.org bugzilla where we dump all > the CPU related issues? Can add that later once a URL is known. > > * attack, so no Speculative Store Bypass > > * control required. > > */ > > +#define ARCH_CAP_MDS_NO (1 << 5) /* No Microarchitectural data sampling */ > > Should this say anything about RDCL? Don't see any point. -Andi