From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:35338 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726295AbeIGOKl (ORCPT ); Fri, 7 Sep 2018 10:10:41 -0400 Date: Fri, 7 Sep 2018 11:30:33 +0200 From: Greg KH To: Jiri Slaby Cc: stable@vger.kernel.org, Andi Kleen Subject: Re: [PATCH v2 for 4.4] x86/mm/pat: Fix L1TF stable backport for CPA, 2nd call Message-ID: <20180907093033.GA9948@kroah.com> References: <20180906202749.siuw4hlnafzq4o23@two.firstfloor.org> <20180907091307.19644-1-jslaby@suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180907091307.19644-1-jslaby@suse.cz> Sender: stable-owner@vger.kernel.org List-ID: On Fri, Sep 07, 2018 at 11:13:07AM +0200, Jiri Slaby wrote: > Mostly recycling the commit log from adaba23ccd7d which fixed > populate_pmd, but did not fix populate_pud. The same problem exists > there. > > Stable trees reverted the following patch: > Revert "x86/mm/pat: Ensure cpa->pfn only contains page frame numbers" > > This reverts commit 87e2bd898d3a79a8c609f183180adac47879a2a4 which is > commit edc3b9129cecd0f0857112136f5b8b1bc1d45918 upstream. > > but the L1TF patch 02ff2769edbc backported here > > x86/mm/pat: Make set_memory_np() L1TF safe > > commit 958f79b9ee55dfaf00c8106ed1c22a2919e0028b upstream > > set_memory_np() is used to mark kernel mappings not present, but it has > it's own open coded mechanism which does not have the L1TF protection of > inverting the address bits. > > assumed that cpa->pfn contains a PFN. With the above patch reverted > it does not, which causes the PUD to be set to an incorrect address > shifted by 12 bits, which can cause various failures. > > Convert the address to a PFN before passing it to pud_pfn(). > > This is a 4.4 stable only patch to fix the L1TF patches backport there. > > Cc: stable@vger.kernel.org # 4.4-only > Cc: Andi Kleen > Signed-off-by: Jiri Slaby > --- > arch/x86/mm/pageattr.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) Thanks for this, now queued up. greg k-h