From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:55204 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725751AbeKYCmN (ORCPT ); Sat, 24 Nov 2018 21:42:13 -0500 Date: Sat, 24 Nov 2018 10:53:27 -0500 From: Sasha Levin To: "Kirill A. Shutemov" Cc: gregkh@linuxfoundation.org, luto@kernel.org, tglx@linutronix.de, stable@vger.kernel.org Subject: Re: FAILED: patch "[PATCH] x86/mm: Move LDT remap out of KASLR region on 5-level paging" failed to apply to 4.18-stable tree Message-ID: <20181124155327.GP1917@sasha-vm> References: <154263023165129@kroah.com> <20181123115320.xjodxpilpv7gxzeu@black.fi.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20181123115320.xjodxpilpv7gxzeu@black.fi.intel.com> Sender: stable-owner@vger.kernel.org List-ID: On Fri, Nov 23, 2018 at 02:53:21PM +0300, Kirill A. Shutemov wrote: >On Mon, Nov 19, 2018 at 12:23:51PM +0000, gregkh@linuxfoundation.org wrote: >> >> The patch below does not apply to the 4.18-stable tree. >> If someone wants it applied there, or to any other stable or longterm >> tree, then please email the backport, including the original git commit >> id to . > >>>From b413460931ab36e958ee127522653cd16f7a248c Mon Sep 17 00:00:00 2001 >From: "Kirill A. Shutemov" >Date: Fri, 26 Oct 2018 15:28:54 +0300 >Subject: [PATCH 1/2] x86/mm: Move LDT remap out of KASLR region on 5-level > paging > >commit d52888aa2753e3063a9d3a0c9f72f94aa9809c15 upstream > >On 5-level paging the LDT remap area is placed in the middle of the KASLR >randomization region and it can overlap with the direct mapping, the >vmalloc or the vmap area. > >The LDT mapping is per mm, so it cannot be moved into the P4D page table >next to the CPU_ENTRY_AREA without complicating PGD table allocation for >5-level paging. > >The 4 PGD slot gap just before the direct mapping is reserved for >hypervisors, so it cannot be used. > >Move the direct mapping one slot deeper and use the resulting gap for the >LDT remap area. The resulting layout is the same for 4 and 5 level paging. > >[ tglx: Massaged changelog ] > >Fixes: f55f0501cbf6 ("x86/pti: Put the LDT in its own PGD if PTI is on") >Signed-off-by: Kirill A. Shutemov >Signed-off-by: Thomas Gleixner >Reviewed-by: Andy Lutomirski >Cc: bp@alien8.de >Cc: hpa@zytor.com >Cc: dave.hansen@linux.intel.com >Cc: peterz@infradead.org >Cc: boris.ostrovsky@oracle.com >Cc: jgross@suse.com >Cc: bhe@redhat.com >Cc: willy@infradead.org >Cc: linux-mm@kvack.org >Cc: stable@vger.kernel.org >Link: https://lkml.kernel.org/r/20181026122856.66224-2-kirill.shutemov@linux.intel.com Queued for 4.18, thank you. -- Thanks, Sasha