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 ; 13 Nov 2018 21:04:14 -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 1gMfr2-0007e2-I4 for speck@linutronix.de; Tue, 13 Nov 2018 22:04:13 +0100 Date: Tue, 13 Nov 2018 13:04:01 -0800 From: "Luck, Tony" Subject: [MODERATED] Re: [PATCH 2/4] RFC-MDSv1 0 Message-ID: <20181113210401.GA23433@agluck-desk> References: MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit To: speck@linutronix.de List-ID: On Tue, Nov 13, 2018 at 09:47:57PM +0100, speck for Jiri Kosina wrote: > Just to make sure, as there has been some confusion around this last time > this has been discussed -- for the above to be true, ucode update is > necessary anyway, right? The L1D flush, as implemented in the current > publicly available ucode, doesn't flush the microarchitectural buffers, > that is only coming with ucode that will provide enhanced verw semantics, > right? Correct. Yuo need a microcode that enumerates MB_CLEAR to tell you that your L1D flush will also flush the micro-architecture structures for MDS. The "old" microcode that was released for L1TF doesn't do this extra flush. -Tony