From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-yw0-f197.google.com (mail-yw0-f197.google.com [209.85.161.197]) by kanga.kvack.org (Postfix) with ESMTP id 5BA316B000D for ; Thu, 26 Jul 2018 19:09:38 -0400 (EDT) Received: by mail-yw0-f197.google.com with SMTP id z78-v6so1670214ywa.23 for ; Thu, 26 Jul 2018 16:09:38 -0700 (PDT) Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id s144-v6sor717900ybc.58.2018.07.26.16.09.37 for (Google Transport Security); Thu, 26 Jul 2018 16:09:37 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: References: <153156030832.10043.13438231886571087086.stgit@srivatsa-ubuntu> From: Kees Cook Date: Thu, 26 Jul 2018 16:09:34 -0700 Message-ID: Subject: Re: [RESEND] Spectre-v2 (IBPB/IBRS) and SSBD fixes for 4.4.y Content-Type: text/plain; charset="UTF-8" Sender: owner-linux-mm@kvack.org List-ID: To: Jiri Kosina Cc: "Srivatsa S. Bhat" , Greg KH , "# 3.4.x" , Denys Vlasenko , Bo Gan , Konrad Rzeszutek Wilk , Borislav Petkov , Thomas Gleixner , Ricardo Neri , Tom Lendacky , Andi Kleen , linux-tip-commits@vger.kernel.org, Jia Zhang , Josh Poimboeuf , xen-devel , =?UTF-8?B?S3LEjW3DocWZ?= , Peter Zijlstra , Andy Lutomirski , Arnaldo Carvalho de Melo , Sherry Hurwitz , LKML , Shuah Khan , Oleg Nesterov , Linus Torvalds , David Woodhouse , KarimAllah Ahmed , Borislav Petkov , Dave Hansen , Dominik Brodowski , Quentin Casasnovas , Joerg Roedel , Alexander Shishkin , Kyle Huey , Will Drewry , Andrey Ryabinin , "H. Peter Anvin" , Brian Gerst , Kristen Carlson Accardi , Thomas Garnier , Andrew Morton , Joe Konno , kvm , Piotr Luc , Boris Ostrovsky , Jan Beulich , Arjan van de Ven , Alexander Kuleshov , Juergen Gross , Ross Zwisler , =?UTF-8?Q?J=C3=B6rg_Otte?= , Tim Chen , Alexander Sergeyev , Josh Triplett , Alan Cox , Tony Luck , Laura Abbott , Dave Hansen , Ingo Molnar , Mike Galbraith , Rik van Riel , "Kirill A. Shutemov" , Alexey Makhalov , Dave Hansen , ashok.raj@intel.com, Mel Gorman , =?UTF-8?B?TWlja2HDq2xTYWxhw7xu?= , Fenghua Yu , "Matt Helsley (VMware)" , Vince Weaver , Prarit Bhargava , Steven Rostedt , Dan Williams , Jim Mattson , Greg Kroah-Hartmann , Dave Young , linux-edac , Jon Masters , Andy Lutomirski , Paolo Bonzini , Arnd Bergmann , Linux-MM , Jiri Olsa , "Van De Ven, Arjan" , sironi@amazon.de, Frederic Weisbecker , Kyle Huey , Alexander Popov , Andy Shevchenko , Nadav Amit , Yazen Ghannam , Wanpeng Li , Stephane Eranian , David Woodhouse , srivatsab@vmware.com On Tue, Jul 24, 2018 at 3:02 PM, Jiri Kosina wrote: > On Tue, 24 Jul 2018, Srivatsa S. Bhat wrote: > >> However, if you are proposing that you'd like to contribute the enhanced >> PTI/Spectre (upstream) patches from the SLES 4.4 tree to 4.4 stable, and >> have them merged instead of this patch series, then I would certainly >> welcome it! > > I'd in principle love us to push everything back to 4.4, but there are a > few reasons (*) why that's not happening shortly. > > Anyway, to point out explicitly what's really needed for those folks > running 4.4-stable and relying on PTI providing The Real Thing(TM), it's > either a 4.4-stable port of > > http://kernel.suse.com/cgit/kernel-source/plain/patches.suse/x86-entry-64-use-a-per-cpu-trampoline-stack.patch?id=3428a77b02b1ba03e45d8fc352ec350429f57fc7 > > or making THREADINFO_GFP imply __GFP_ZERO. This is true in Linus's tree now. Should be trivial to backport: https://git.kernel.org/linus/e01e80634ecdd -Kees -- Kees Cook Pixel Security