From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934313AbeALO2S (ORCPT + 1 other); Fri, 12 Jan 2018 09:28:18 -0500 Received: from twin.jikos.cz ([91.219.245.39]:41767 "EHLO twin.jikos.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933846AbeALO2Q (ORCPT ); Fri, 12 Jan 2018 09:28:16 -0500 Date: Fri, 12 Jan 2018 15:27:32 +0100 (CET) From: Jiri Kosina To: Pavel Tatashin cc: steven.sistare@oracle.com, linux-kernel@vger.kernel.org, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, x86@kernel.org, gregkh@linuxfoundation.org, jkosina@suse.cz, hughd@google.com, dave.hansen@linux.intel.com, luto@kernel.org, torvalds@linux-foundation.org Subject: Re: [PATCH 4.9] x86/pti/efi: broken conversion from efi to kernel page table In-Reply-To: <20180111215820.29736-1-pasha.tatashin@oracle.com> Message-ID: References: <20180111215820.29736-1-pasha.tatashin@oracle.com> User-Agent: Alpine 2.00 (LRH 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: On Thu, 11 Jan 2018, Pavel Tatashin wrote: > The page table order must be increased for EFI table in order to avoid a > bug where NMI tries to change the page table to kernel page table, while > efi page table is active. > > For more disccussion about this bug, see this thread: > http://lkml.iu.edu/hypermail/linux/kernel/1801.1/00951.html > > Signed-off-by: Pavel Tatashin > Reviewed-by: Steven Sistare Acked-by: Jiri Kosina We are carrying similar patch in our 4.4 codestream as well. Please note that this is needed only for those trees that have 67a9108ed43 ("x86/efi: Build our own page table structures") backported to it. That used to be in some -stable releases, and some had it reverted, so please check that. -- Jiri Kosina SUSE Labs