From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f199.google.com (mail-pf0-f199.google.com [209.85.192.199]) by kanga.kvack.org (Postfix) with ESMTP id 2770B6B025F for ; Mon, 28 Aug 2017 18:35:14 -0400 (EDT) Received: by mail-pf0-f199.google.com with SMTP id v22so2648453pfk.4 for ; Mon, 28 Aug 2017 15:35:14 -0700 (PDT) Received: from mga03.intel.com (mga03.intel.com. [134.134.136.65]) by mx.google.com with ESMTPS id 97si1100791ple.533.2017.08.28.15.35.12 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 28 Aug 2017 15:35:13 -0700 (PDT) Date: Mon, 28 Aug 2017 15:35:11 -0700 From: Andi Kleen Subject: Re: [PATCH v2 14/20] mm: Provide speculative fault infrastructure Message-ID: <20170828223511.GM28715@tassilo.jf.intel.com> References: <1503007519-26777-1-git-send-email-ldufour@linux.vnet.ibm.com> <1503007519-26777-15-git-send-email-ldufour@linux.vnet.ibm.com> <20170827001823.n5wgkfq36z6snvf2@node.shutemov.name> <20170828093727.5wldedputadanssh@hirez.programming.kicks-ass.net> <1503954877.4850.19.camel@kernel.crashing.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1503954877.4850.19.camel@kernel.crashing.org> Sender: owner-linux-mm@kvack.org List-ID: To: Benjamin Herrenschmidt Cc: Peter Zijlstra , "Kirill A. Shutemov" , Laurent Dufour , paulmck@linux.vnet.ibm.com, akpm@linux-foundation.org, mhocko@kernel.org, dave@stgolabs.net, jack@suse.cz, Matthew Wilcox , mpe@ellerman.id.au, paulus@samba.org, Thomas Gleixner , Ingo Molnar , hpa@zytor.com, Will Deacon , linux-kernel@vger.kernel.org, linux-mm@kvack.org, haren@linux.vnet.ibm.com, khandual@linux.vnet.ibm.com, npiggin@gmail.com, bsingharora@gmail.com, Tim Chen , linuxppc-dev@lists.ozlabs.org, x86@kernel.org > That makes me extremely nervous... there could be all sort of > assumptions esp. in arch code about the fact that we never populate the > tree without the mm sem. > > We'd have to audit archs closely. Things like the page walk cache > flushing on power etc... Yes the whole thing is quite risky. Probably will need some kind of per architecture opt-in scheme? -Andi -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org