From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linutronix.de (193.142.43.55:993) by crypto-ml.lab.linutronix.de with IMAP4-SSL for ; 16 Oct 2019 04:52:35 -0000 Received: from mx2.suse.de ([195.135.220.15] helo=mx1.suse.de) by Galois.linutronix.de with esmtps (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1iKbIW-0005Mr-Ou for speck@linutronix.de; Wed, 16 Oct 2019 06:52:34 +0200 Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 6401CB20F for ; Wed, 16 Oct 2019 04:52:22 +0000 (UTC) Date: Wed, 16 Oct 2019 06:52:15 +0200 (CEST) From: Jiri Kosina Subject: [MODERATED] Re: [PATCH v5 08/11] TAAv5 8 In-Reply-To: <20191015231252.kggxh6ffrciz2dfy@treble> Message-ID: References: <20191015103454.GW317@dhcp22.suse.cz> <20191015130627.7jkhqy2zrtm35ool@treble> <20191015152649.yim4krwuttrh6xgi@treble> <20191015200024.hxs4brxi7gbvmcdy@treble> <20191015205631.GF30412@guptapadev.amr> <20191015231252.kggxh6ffrciz2dfy@treble> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit To: speck@linutronix.de List-ID: yOn Tue, 15 Oct 2019, speck for Josh Poimboeuf wrote: > So if I understand correctly, you're postulating that distros want: > > a) TAA_BUG && MDS_NO=0 => TSX on > b) TAA_BUG && MDS_NO=1 => TSX off > c) !TAA_BUG => TSX on > > How are you reaching that conclusion? It seems horribly confusing for > TSX users, but again maybe I'm missing something. > > It seems to me that "heavy users of TSX" would want tsx=on, no matter > what. And so we would need to leave that as the default in order to not > break those users. But then we're not defaulting to safe behavior, which is confusing too, because we almost (SMT being the exception) always did in the past for all the other previous issues. So I believe the above is the best compromise between having as few regressions as possible, while still maintaining security (by default). I agree it's not nice, but nothing is, if you ask me. -- Jiri Kosina SUSE Labs