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[209.132.180.67]) by mx.google.com with ESMTP id z1si1822105pgs.409.2018.02.09.13.14.11; Fri, 09 Feb 2018 13:14:25 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=fail header.i=@gmail.com header.s=20161025 header.b=U7dOqKjR; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752875AbeBIVLz (ORCPT + 99 others); Fri, 9 Feb 2018 16:11:55 -0500 Received: from mail-it0-f66.google.com ([209.85.214.66]:37854 "EHLO mail-it0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752651AbeBIVLy (ORCPT ); Fri, 9 Feb 2018 16:11:54 -0500 Received: by mail-it0-f66.google.com with SMTP id h129so12302682ita.2 for ; Fri, 09 Feb 2018 13:11:53 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:sender:in-reply-to:references:from:date:message-id :subject:to:cc; bh=NWCzzmAK5+PN39/5/AVPnRubzqgqNfBFcjCucHck7a8=; b=U7dOqKjRvwu0xsp0gBYh1TuhT9bEunJM/vByTO4NTxK+SU59O7xFZIo+w3A3pwAV0Z Vs/MxS9SxQyAvK0RByGYGMESkoJ+TiILQ4KvfIkJVk8S8bILGCQDwD8J26WUaAwRm1uA ohm1uDwwh/sxZye8kilvQNbD8CanXmrE6NYLg/K6sMyNxM7fpcAEszVuVewOAKOqhWio NHF0tYGZjQ2MLYsdLuMnLDaWjE5MCeqXbsWUCGc6VJT4VCRzmhI5W6z9U6EldMDnAtTA SKL5uSlzegbyTj3Nj/HkrFHNdghQ59anm3n8jRbgNOb2K8nfrMlE+lE9dAsVblZnNN/0 Nqyw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:sender:in-reply-to:references:from :date:message-id:subject:to:cc; bh=NWCzzmAK5+PN39/5/AVPnRubzqgqNfBFcjCucHck7a8=; b=mYKJXArdGSRnMNe4MGbj5S+TDYt700Q+wxrZ05SXZvYlz+VU9NRqTmysBRVbck/zmc 36RWUj6RELuEwmI/1X4a5mwvv9K5my5iT0aRJGY5pwHHkfqaMrQiLMnTWeBSsgZTO6M1 en5vomHigF/OY8TY6im6YmBMG7Uywnu0U+drV6vKHu3Q9lnOiA+4TW3MNb8PP291Yi4C yqFZsP9YOfF90OoedXZloG1ndqx3qlKJ6u0uhA0giS+HTmFIAaroLatfHFl89ipJfn+K Cg7b67HrOFRFQF+4B77yi/c8tTBriPqCFM827bb6pbDUWfE6pUDmgfzsjKVJ1+ZBEsvL fmWQ== X-Gm-Message-State: APf1xPCpHVus27DieoO3EZIEDUlVskWdITeGK9PVyLYWA06KDsBRD+0s wilnakHy3wp58n+Zx4+y1OwD3F8cAwcADG5Bf5Q= X-Received: by 10.36.179.14 with SMTP id e14mr5265656itf.139.1518210713120; Fri, 09 Feb 2018 13:11:53 -0800 (PST) MIME-Version: 1.0 Received: by 10.107.59.196 with HTTP; Fri, 9 Feb 2018 13:11:52 -0800 (PST) In-Reply-To: <20180209210918.GA7333@amd> References: <1518168340-9392-1-git-send-email-joro@8bytes.org> <20180209210918.GA7333@amd> From: Linus Torvalds Date: Fri, 9 Feb 2018 13:11:52 -0800 X-Google-Sender-Auth: FVne5RTOWomjJyJ1GXNmkiTC9EA Message-ID: Subject: Re: [PATCH 00/31 v2] PTI support for x86_32 To: Pavel Machek Cc: Andy Lutomirski , Joerg Roedel , Thomas Gleixner , Ingo Molnar , "H . Peter Anvin" , X86 ML , LKML , Linux-MM , Dave Hansen , Josh Poimboeuf , Juergen Gross , Peter Zijlstra , Borislav Petkov , Jiri Kosina , Boris Ostrovsky , Brian Gerst , David Laight , Denys Vlasenko , Eduardo Valentin , Greg KH , Will Deacon , "Liguori, Anthony" , Daniel Gruss , Hugh Dickins , Kees Cook , Andrea Arcangeli , Waiman Long , Joerg Roedel Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Feb 9, 2018 at 1:09 PM, Pavel Machek wrote: > > Hardware supports PCID even on 32-bit kernels, no? We're not adding support for it even if it were possible. No way. Christ, even if you want to run 32-bit user code, you'd better run a 64-bit kernel. Backporting the PCID bits to something that no actual real developer will ever use is crazy and unacceptable. Linus