From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F3636C4321D for ; Fri, 24 Aug 2018 03:35:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A6CA3208A6 for ; Fri, 24 Aug 2018 03:35:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A6CA3208A6 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727524AbeHXHIX (ORCPT ); Fri, 24 Aug 2018 03:08:23 -0400 Received: from mga03.intel.com ([134.134.136.65]:39453 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726085AbeHXHIX (ORCPT ); Fri, 24 Aug 2018 03:08:23 -0400 X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga103.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 23 Aug 2018 20:35:40 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.53,280,1531810800"; d="scan'208";a="85979268" Received: from tassilo.jf.intel.com (HELO tassilo.localdomain) ([10.7.201.126]) by orsmga002.jf.intel.com with ESMTP; 23 Aug 2018 20:35:40 -0700 Received: by tassilo.localdomain (Postfix, from userid 1000) id 63E37301B8F; Thu, 23 Aug 2018 20:35:40 -0700 (PDT) Date: Thu, 23 Aug 2018 20:35:40 -0700 From: Andi Kleen To: Andre Tomt Cc: Vlastimil Babka , Thomas Gleixner , Ingo Molnar , "H . Peter Anvin" , x86@kernel.org, linux-kernel@vger.kernel.org, Linus Torvalds , Dave Hansen , Michal Hocko , stable@vger.kernel.org, Christopher Snowhill , George Anchev Subject: Re: [PATCH] x86/speculation/l1tf: fix off-by-one error when warning that system has too much RAM Message-ID: <20180824033540.GI12066@tassilo.jf.intel.com> References: <20180823134418.17008-1-vbabka@suse.cz> <20180823154437.GC12066@tassilo.jf.intel.com> <0fa72221-2272-4489-d9d3-0f68cb874087@tomt.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <0fa72221-2272-4489-d9d3-0f68cb874087@tomt.net> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Aug 24, 2018 at 04:22:57AM +0200, Andre Tomt wrote: > On 23. aug. 2018 17:44, Andi Kleen wrote: > > On Thu, Aug 23, 2018 at 03:44:18PM +0200, Vlastimil Babka wrote: > > > Two users have reported [1] that they have an "extremely unlikely" system > > > with more than MAX_PA/2 memory and L1TF mitigation is not effective. In fact > > > it's a CPU with 36bits phys limit (64GB) and 32GB memory, but due to holes > > > in the e820 map, the main region is almost 500MB over the 32GB limit: > > > > Ah I see it's a client part with very large DIMMs and someone being > > very brave and using that much memory without ECC. > > FYI; It is also happening on Xeon E3v2 (Ivy Bridge generation) w/ 32GB of > ECC RAM here, a low-end server part that officially supports up to 32GB. Good point. -andi