From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io0-f197.google.com (mail-io0-f197.google.com [209.85.223.197]) by kanga.kvack.org (Postfix) with ESMTP id C3B086B0033 for ; Tue, 7 Feb 2017 14:24:42 -0500 (EST) Received: by mail-io0-f197.google.com with SMTP id m98so121259333iod.2 for ; Tue, 07 Feb 2017 11:24:42 -0800 (PST) Received: from mail-io0-x22f.google.com (mail-io0-x22f.google.com. [2607:f8b0:4001:c06::22f]) by mx.google.com with ESMTPS id j130si12628469iof.9.2017.02.07.11.24.42 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 07 Feb 2017 11:24:42 -0800 (PST) Received: by mail-io0-x22f.google.com with SMTP id j13so98156860iod.3 for ; Tue, 07 Feb 2017 11:24:42 -0800 (PST) MIME-Version: 1.0 In-Reply-To: References: From: Thomas Garnier Date: Tue, 7 Feb 2017 11:24:41 -0800 Message-ID: Subject: Re: PCID review? Content-Type: text/plain; charset=UTF-8 Sender: owner-linux-mm@kvack.org List-ID: To: Kees Cook Cc: Andy Lutomirski , Borislav Petkov , Dave Hansen , "linux-mm@kvack.org" , "Paul E. McKenney" On Tue, Feb 7, 2017 at 11:11 AM, Kees Cook wrote: > On Tue, Feb 7, 2017 at 10:56 AM, Andy Lutomirski wrote: >> Quite a few people have expressed interest in enabling PCID on (x86) >> Linux. Here's the code: >> >> https://git.kernel.org/cgit/linux/kernel/git/luto/linux.git/log/?h=x86/pcid >> >> The main hold-up is that the code needs to be reviewed very carefully. >> It's quite subtle. In particular, "x86/mm: Try to preserve old TLB >> entries using PCID" ought to be looked at carefully to make sure the >> locking is right, but there are plenty of other ways this this could >> all break. >> >> Anyone want to take a look or maybe scare up some other reviewers? >> (Kees, you seemed *really* excited about getting this in.) > > Yeah, I'd really like to build on it to gain SMAP emulation, though > both implementing that and reviewing the existing series is outside my > current skills (well, okay, you could add "Reviewed-by:"-me to the > first 3 patches ;)). I don't know Intel guts well enough to > meaningfully do anything on the others. :) > > I've added Thomas Garnier to CC, in case this is something he might be > able to assist with. It would be great to add but I have limited cycles and definitely lacking knowledge on that front. > > Does this need benchmarking or other testing? Perhaps bring it to the > kernel-hardening list for that? > > Also, what's needed to gain SMAP emulation? > > -Kees > > -- > Kees Cook > Pixel Security -- Thomas -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org