From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf1-f197.google.com (mail-pf1-f197.google.com [209.85.210.197]) by kanga.kvack.org (Postfix) with ESMTP id F32016B0003 for ; Wed, 14 Nov 2018 19:27:46 -0500 (EST) Received: by mail-pf1-f197.google.com with SMTP id t2so5709254pfj.15 for ; Wed, 14 Nov 2018 16:27:46 -0800 (PST) Received: from mga17.intel.com (mga17.intel.com. [192.55.52.151]) by mx.google.com with ESMTPS id c11si25116463pgj.255.2018.11.14.16.27.45 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 14 Nov 2018 16:27:45 -0800 (PST) Date: Wed, 14 Nov 2018 16:27:44 -0800 From: Andi Kleen Subject: Re: [PATCH] l1tf: drop the swap storage limit restriction when l1tf=off Message-ID: <20181115002744.GM6218@tassilo.jf.intel.com> References: <20181113184910.26697-1-mhocko@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181113184910.26697-1-mhocko@kernel.org> Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: Thomas Gleixner , Jiri Kosina , Linus Torvalds , Dave Hansen , Borislav Petkov , LKML , linux-mm@kvack.org, Michal Hocko On Tue, Nov 13, 2018 at 07:49:10PM +0100, Michal Hocko wrote: > From: Michal Hocko > > Swap storage is restricted to max_swapfile_size (~16TB on x86_64) > whenever the system is deemed affected by L1TF vulnerability. Even > though the limit is quite high for most deployments it seems to be > too restrictive for deployments which are willing to live with the > mitigation disabled. > > We have a customer to deploy 8x 6,4TB PCIe/NVMe SSD swap devices > which is clearly out of the limit. > > Drop the swap restriction when l1tf=off is specified. It also doesn't > make much sense to warn about too much memory for the l1tf mitigation > when it is forcefully disabled by the administrator. Reviewed-by: Andi Kleen -Andi