From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on archive.lwn.net X-Spam-Level: X-Spam-Status: No, score=-5.6 required=5.0 tests=DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, T_DKIM_INVALID autolearn=ham autolearn_force=no version=3.4.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by archive.lwn.net (Postfix) with ESMTP id 15DDC7D043 for ; Fri, 29 Jun 2018 16:36:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S967080AbeF2QgP (ORCPT ); Fri, 29 Jun 2018 12:36:15 -0400 Received: from mail-io0-f196.google.com ([209.85.223.196]:38011 "EHLO mail-io0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S967076AbeF2QgM (ORCPT ); Fri, 29 Jun 2018 12:36:12 -0400 Received: by mail-io0-f196.google.com with SMTP id l19-v6so8996055ioj.5 for ; Fri, 29 Jun 2018 09:36:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=ukCGltYwtD7YajTlWIOjEevOj1qICTIHzaLGC+IF44g=; b=JeIYMbIX3IAluQh6MhELO7TmAfHyd6W5UTGw3TRp98mmofrXYoYtTUtXjEsX6Ja/lq AzFWQLQA9opUNjazc24TrHLOeQqIUBty+fE+AMmdg8MNi5Vb8PFN6M+zWbl2VQqqz7KG XqUmwT2Po6HofXqvK2C0KMAsyjjp2HvNqI7CqGGTFPAALmXM/GDAZn7Tjw8qiX5v6D05 kIFhixws/cWz1KdMi+3IfGVUFdfBUdbfZ3B2vnOmkjv5MiD9YLK21PanXHrDwaRD+IsY FH96sKlVbvIL+Uxlidq2LSVZwjAmrtRyptb5HeFJI/vP8FoN07z1OAYievrniflL+eZu hnmw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=ukCGltYwtD7YajTlWIOjEevOj1qICTIHzaLGC+IF44g=; b=OjCv1Uor5N8ROwEv8G5u+53x29f4rWiXABmH35plwXYTf9b464z24r3hJ4JAKJhQuz S+8UCx5n0LGgabwvqarNmAMNu56iel+gnlGAfcY4i8BShU/3WVun4L0GXw9Shoskyo62 eKprczVp4vQXptsgzWUA7EUf7he+eICqc9E/OhAtRVM1xcmBIAh6l8AL00sAe4dk3k8T DK6H4Pguwowx0haF2ksSinCGewBNjEMHwzoV7tf408PHJHd3ZPEVKelaBEuxkp+r/HXe odzoGdYAWhNADu3GC/nLxRf7w7isKMp0Ve+mTQKf8h1FGpqLorGbJ5s9h/Ezi8xNmVTe DmIg== X-Gm-Message-State: APt69E0kNHN9YFUG8xKeZs56JIFtUNSVoXfWVUWqynszdIJiaXUK+Ctf DgXqN7+HSDm5RMcMoXbODQbIL1C8QvST89YuCjZogw== X-Google-Smtp-Source: AAOMgpe1SW9csFvdGv+80VIVjSOgp82ktPCy4rDxxGN2dKxq3LBu2kI150jfQjseKfH6aCeXYeCHu4NmnWZXjuwGnps= X-Received: by 2002:a6b:5002:: with SMTP id e2-v6mr13329662iob.31.1530290171709; Fri, 29 Jun 2018 09:36:11 -0700 (PDT) MIME-Version: 1.0 Received: by 2002:a02:9082:0:0:0:0:0 with HTTP; Fri, 29 Jun 2018 09:36:10 -0700 (PDT) In-Reply-To: <20180629110709.GA17859@arm.com> References: <20180628105057.GA26019@e103592.cambridge.arm.com> <20180629110709.GA17859@arm.com> From: Andrey Konovalov Date: Fri, 29 Jun 2018 18:36:10 +0200 Message-ID: Subject: Re: [PATCH v4 00/17] khwasan: kernel hardware assisted address sanitizer To: Will Deacon Cc: Dave Martin , Andrey Ryabinin , Alexander Potapenko , Dmitry Vyukov , Catalin Marinas , Christoph Lameter , Andrew Morton , Mark Rutland , Nick Desaulniers , Marc Zyngier , Ard Biesheuvel , "Eric W . Biederman" , Ingo Molnar , Paul Lawrence , Geert Uytterhoeven , Arnd Bergmann , "Kirill A . Shutemov" , Greg Kroah-Hartman , Kate Stewart , Mike Rapoport , kasan-dev , linux-doc@vger.kernel.org, LKML , Linux ARM , linux-sparse@vger.kernel.org, Linux Memory Management List , Linux Kbuild mailing list , Chintan Pandya , Jacob Bramley , Jann Horn , Ruben Ayrapetyan , Lee Smith , Kostya Serebryany , Mark Brand , Ramana Radhakrishnan , Evgeniy Stepanov Content-Type: text/plain; charset="UTF-8" Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On Fri, Jun 29, 2018 at 1:07 PM, Will Deacon wrote: > It might not seen sensible, but we could still be relying on this in the > kernel and so this change would introduce a regression. I think we need > a way to identify such pointer usage before these patches can seriously be > considered for mainline inclusion. Another point that I have here is that KHWASAN is a debugging tool not meant to be used in production. We're not trying to change the ABI or something like that (referring to the other HWASAN patchset). We can fix up the non obvious places where untagging is needed in a case by case basis with additional patches when testing reveals it. -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html