From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-14.4 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 10531C47423 for ; Fri, 2 Oct 2020 06:09:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C22A4206DC for ; Fri, 2 Oct 2020 06:09:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="rBhLzpe9" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726051AbgJBGJX (ORCPT ); Fri, 2 Oct 2020 02:09:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34144 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725968AbgJBGJX (ORCPT ); Fri, 2 Oct 2020 02:09:23 -0400 Received: from mail-ej1-x644.google.com (mail-ej1-x644.google.com [IPv6:2a00:1450:4864:20::644]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 77C86C0613E2 for ; Thu, 1 Oct 2020 23:09:21 -0700 (PDT) Received: by mail-ej1-x644.google.com with SMTP id p9so323068ejf.6 for ; Thu, 01 Oct 2020 23:09:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=ErDIuUWMtALu7PV5gTspIOaPecBO2jLlFmry3dq1eBo=; b=rBhLzpe9AaLtN/2VQTeF4ZLBJk0wEwLO1iXW7SFdIMCovz/n+bZLB7IAveG1e9ur8g YRDBg+0/O3HVIFt9+77VO4vz1qRhWN0N5JLUJkLHeKN0Fq2FV1sS8zieRMheOhUf5bVF 9qAS9mTkKdzWHR4dJan0mJZrLW9vG6XzX1iipaUrffpCB3CFAGIdFAOD70DlWd/BV/00 YeempllyPkiOQYQTjPfz7FvV8Zq35XFb+EARWaMiaC9negdQ9wmS4SToBah7FpromM0/ j46OcFr+y/fWE9HUSVM5XGUXZ/ifypV3vicbNueD/Gkh591QW2pcf6xwTpu/Kqy1srWq wZGQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=ErDIuUWMtALu7PV5gTspIOaPecBO2jLlFmry3dq1eBo=; b=I6AaMS8lzZmxfzl2t+jxxVIQVYNwLFrgmEDO9eB95qZMWW2oo6jd2KG01IMVW4XuRC /068Qt3+s4vDkos/+bal5PRFzHmxQgrKqiSOmzpiIw62OI78nou9D2wVZnpJX8B2VOSb SjfhU+Stn+seI/B2gvW+fqGlZVJqUJ74AKdP/z/APLdwbjvHdmuUUZuJmd6Wn55qX5Z+ H5iZO2gvzLuLqYXlHyMGgKrgh32TilJtn4H3GIl+R89TSodHQcWT6i5XVkNMJCI80tm+ 8qyvYVjh1Tg2NOFMIBSd+CbCgogTef+mY9/uwV3TOKSKf1Y2Ro4thpQ2WJ1hy9Q2eK4n ySFA== X-Gm-Message-State: AOAM530Vy6BVQz97IBL5Cj0QyVVklrCY4yPkXT2gJinFj7Wy4LVsRhKv ph9j1q/sHrcWe43+J67dP0iqNtQ21e9Ezqb1jdwzOw== X-Google-Smtp-Source: ABdhPJyX8T+V5wOYpGANjLoJVq9hy+yf3n4BHwp6BilkYq6bai5LeCuRrBuF1aQ5IgShwbEHdu8lTpaX6/0OCPdGKR4= X-Received: by 2002:a17:906:394:: with SMTP id b20mr570705eja.513.1601618959814; Thu, 01 Oct 2020 23:09:19 -0700 (PDT) MIME-Version: 1.0 References: <20200929133814.2834621-1-elver@google.com> <20200929133814.2834621-3-elver@google.com> In-Reply-To: <20200929133814.2834621-3-elver@google.com> From: Jann Horn Date: Fri, 2 Oct 2020 08:08:53 +0200 Message-ID: Subject: Re: [PATCH v4 02/11] x86, kfence: enable KFENCE for x86 To: Marco Elver Cc: Andrew Morton , Alexander Potapenko , "H . Peter Anvin" , "Paul E . McKenney" , Andrey Konovalov , Andrey Ryabinin , Andy Lutomirski , Borislav Petkov , Catalin Marinas , Christoph Lameter , Dave Hansen , David Rientjes , Dmitry Vyukov , Eric Dumazet , Greg Kroah-Hartman , Hillf Danton , Ingo Molnar , Jonathan.Cameron@huawei.com, Jonathan Corbet , Joonsoo Kim , Kees Cook , Mark Rutland , Pekka Enberg , Peter Zijlstra , sjpark@amazon.com, Thomas Gleixner , Vlastimil Babka , Will Deacon , "the arch/x86 maintainers" , linux-doc@vger.kernel.org, kernel list , kasan-dev , Linux ARM , Linux-MM Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 29, 2020 at 3:38 PM Marco Elver wrote: > Add architecture specific implementation details for KFENCE and enable > KFENCE for the x86 architecture. In particular, this implements the > required interface in for setting up the pool and > providing helper functions for protecting and unprotecting pages. [...] > diff --git a/arch/x86/include/asm/kfence.h b/arch/x86/include/asm/kfence.h [...] > +/* Protect the given page and flush TLBs. */ > +static inline bool kfence_protect_page(unsigned long addr, bool protect) > +{ [...] > + flush_tlb_one_kernel(addr); flush_tlb_one_kernel() -> flush_tlb_one_user() -> __flush_tlb_one_user() -> native_flush_tlb_one_user() only flushes on the local CPU core, not on others. If you want to leave it this way, I think this needs a comment explaining why we're not doing a global flush (locking context / performance overhead / ... ?). From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-14.4 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A773CC4727F for ; Fri, 2 Oct 2020 06:09:23 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 2C621206DD for ; Fri, 2 Oct 2020 06:09:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="rBhLzpe9" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2C621206DD Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 678658E0003; Fri, 2 Oct 2020 02:09:22 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 627B08E0001; Fri, 2 Oct 2020 02:09:22 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 4F0E68E0003; Fri, 2 Oct 2020 02:09:22 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0217.hostedemail.com [216.40.44.217]) by kanga.kvack.org (Postfix) with ESMTP id 235B28E0001 for ; Fri, 2 Oct 2020 02:09:22 -0400 (EDT) Received: from smtpin11.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id B0705181AE873 for ; Fri, 2 Oct 2020 06:09:21 +0000 (UTC) X-FDA: 77325958122.11.cord42_3c16174271a1 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin11.hostedemail.com (Postfix) with ESMTP id 88E2C180F8B80 for ; Fri, 2 Oct 2020 06:09:21 +0000 (UTC) X-HE-Tag: cord42_3c16174271a1 X-Filterd-Recvd-Size: 4770 Received: from mail-ej1-f68.google.com (mail-ej1-f68.google.com [209.85.218.68]) by imf33.hostedemail.com (Postfix) with ESMTP for ; Fri, 2 Oct 2020 06:09:21 +0000 (UTC) Received: by mail-ej1-f68.google.com with SMTP id p15so318743ejm.7 for ; Thu, 01 Oct 2020 23:09:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=ErDIuUWMtALu7PV5gTspIOaPecBO2jLlFmry3dq1eBo=; b=rBhLzpe9AaLtN/2VQTeF4ZLBJk0wEwLO1iXW7SFdIMCovz/n+bZLB7IAveG1e9ur8g YRDBg+0/O3HVIFt9+77VO4vz1qRhWN0N5JLUJkLHeKN0Fq2FV1sS8zieRMheOhUf5bVF 9qAS9mTkKdzWHR4dJan0mJZrLW9vG6XzX1iipaUrffpCB3CFAGIdFAOD70DlWd/BV/00 YeempllyPkiOQYQTjPfz7FvV8Zq35XFb+EARWaMiaC9negdQ9wmS4SToBah7FpromM0/ j46OcFr+y/fWE9HUSVM5XGUXZ/ifypV3vicbNueD/Gkh591QW2pcf6xwTpu/Kqy1srWq wZGQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=ErDIuUWMtALu7PV5gTspIOaPecBO2jLlFmry3dq1eBo=; b=stRRudDNsu4SxMhDne3+jlWm+S25+P0TinuwpoQq5ZZHnkSNBF3W9QlCW5YGzMdqr+ ONzspu020gSjgP3n/FRIDUkBlKGsXrmfG08/cEcANgHFR8qPWGFcKhR45/LTx18ZJdeA Qfyl36A2Ly0j4U11o1BCNFCNGflbsFBmslXUg/BFZd7X/NmJONVL9djX10m0IXpN0cqo Q8FxThRaot9unk7ywdtgKBqOdpvspOd2dK7ZPi008aXSHlSCjz0FFPW3E/1fICM9Ef2p owM9aQnyGueEfNBhzDmgMqv80U1drNocUwojtR8dH888yEgNm+/3ptppsZhfmGxMmgFF 6tmA== X-Gm-Message-State: AOAM533MeDH0/8Xqj8wc/f4vRqwKQK6BSJlW40J/xT6xIuTA6PBbqOn3 n5gefLDlr6BHq2BmMelvEFAnvet3Elzcaxdhg5/w9Q== X-Google-Smtp-Source: ABdhPJyX8T+V5wOYpGANjLoJVq9hy+yf3n4BHwp6BilkYq6bai5LeCuRrBuF1aQ5IgShwbEHdu8lTpaX6/0OCPdGKR4= X-Received: by 2002:a17:906:394:: with SMTP id b20mr570705eja.513.1601618959814; Thu, 01 Oct 2020 23:09:19 -0700 (PDT) MIME-Version: 1.0 References: <20200929133814.2834621-1-elver@google.com> <20200929133814.2834621-3-elver@google.com> In-Reply-To: <20200929133814.2834621-3-elver@google.com> From: Jann Horn Date: Fri, 2 Oct 2020 08:08:53 +0200 Message-ID: Subject: Re: [PATCH v4 02/11] x86, kfence: enable KFENCE for x86 To: Marco Elver Cc: Andrew Morton , Alexander Potapenko , "H . Peter Anvin" , "Paul E . McKenney" , Andrey Konovalov , Andrey Ryabinin , Andy Lutomirski , Borislav Petkov , Catalin Marinas , Christoph Lameter , Dave Hansen , David Rientjes , Dmitry Vyukov , Eric Dumazet , Greg Kroah-Hartman , Hillf Danton , Ingo Molnar , Jonathan.Cameron@huawei.com, Jonathan Corbet , Joonsoo Kim , Kees Cook , Mark Rutland , Pekka Enberg , Peter Zijlstra , sjpark@amazon.com, Thomas Gleixner , Vlastimil Babka , Will Deacon , "the arch/x86 maintainers" , linux-doc@vger.kernel.org, kernel list , kasan-dev , Linux ARM , Linux-MM Content-Type: text/plain; charset="UTF-8" X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Sep 29, 2020 at 3:38 PM Marco Elver wrote: > Add architecture specific implementation details for KFENCE and enable > KFENCE for the x86 architecture. In particular, this implements the > required interface in for setting up the pool and > providing helper functions for protecting and unprotecting pages. [...] > diff --git a/arch/x86/include/asm/kfence.h b/arch/x86/include/asm/kfence.h [...] > +/* Protect the given page and flush TLBs. */ > +static inline bool kfence_protect_page(unsigned long addr, bool protect) > +{ [...] > + flush_tlb_one_kernel(addr); flush_tlb_one_kernel() -> flush_tlb_one_user() -> __flush_tlb_one_user() -> native_flush_tlb_one_user() only flushes on the local CPU core, not on others. If you want to leave it this way, I think this needs a comment explaining why we're not doing a global flush (locking context / performance overhead / ... ?). 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a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=ErDIuUWMtALu7PV5gTspIOaPecBO2jLlFmry3dq1eBo=; b=Z1o3UlNL6i+Zd26w/GVpnjJF6QeQJ/PeeQueYDm33X2Sp3gAY7FxrijSSZdgLv+3mD KLN1z9ndpOQm7un1Yed+vXIq7C6YOd3STH5z6ucHM3F/+TpEiiJ8NTLFmAlL/9uou3go LWHrnqZBX8e9X5gzqaY+a+dF+VF/Q6XbGNxVDX5ZDQgo6EItTS7lPDp3PQsyhXskKIDA 5UMIFp8Pd5DPasq4/apuwaQ2le4RjT6ALuJ1rGGjQnwsYQ0guL1oFRvydKZv2l+HazEU 3sJgk5XNblW89CqqCV0w5Yw+Ba5X8YzjF2laGYzLrRS5OEcCS+vNssObYpFYc5fIPWYS 8/SA== X-Gm-Message-State: AOAM533IFkoMonyAi+bPojDu/fXrtV6ko5xihlNo7gEO62Di1b/1R93H innh7bptYKYKt94LvTG4j2DYryxEOz100SYobMKCuw== X-Google-Smtp-Source: ABdhPJyX8T+V5wOYpGANjLoJVq9hy+yf3n4BHwp6BilkYq6bai5LeCuRrBuF1aQ5IgShwbEHdu8lTpaX6/0OCPdGKR4= X-Received: by 2002:a17:906:394:: with SMTP id b20mr570705eja.513.1601618959814; Thu, 01 Oct 2020 23:09:19 -0700 (PDT) MIME-Version: 1.0 References: <20200929133814.2834621-1-elver@google.com> <20200929133814.2834621-3-elver@google.com> In-Reply-To: <20200929133814.2834621-3-elver@google.com> From: Jann Horn Date: Fri, 2 Oct 2020 08:08:53 +0200 Message-ID: Subject: Re: [PATCH v4 02/11] x86, kfence: enable KFENCE for x86 To: Marco Elver X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201002_020922_152885_C2B383FE X-CRM114-Status: GOOD ( 15.09 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Hillf Danton , linux-doc@vger.kernel.org, Peter Zijlstra , Catalin Marinas , Dave Hansen , Linux-MM , Eric Dumazet , Alexander Potapenko , "H . Peter Anvin" , Christoph Lameter , Will Deacon , sjpark@amazon.com, Jonathan Corbet , the arch/x86 maintainers , kasan-dev , Ingo Molnar , Vlastimil Babka , David Rientjes , Andrey Ryabinin , Kees Cook , "Paul E . McKenney" , Andrey Konovalov , Borislav Petkov , Andy Lutomirski , Jonathan.Cameron@huawei.com, Thomas Gleixner , Andrew Morton , Dmitry Vyukov , Linux ARM , Greg Kroah-Hartman , kernel list , Pekka Enberg , Joonsoo Kim Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Sep 29, 2020 at 3:38 PM Marco Elver wrote: > Add architecture specific implementation details for KFENCE and enable > KFENCE for the x86 architecture. In particular, this implements the > required interface in for setting up the pool and > providing helper functions for protecting and unprotecting pages. [...] > diff --git a/arch/x86/include/asm/kfence.h b/arch/x86/include/asm/kfence.h [...] > +/* Protect the given page and flush TLBs. */ > +static inline bool kfence_protect_page(unsigned long addr, bool protect) > +{ [...] > + flush_tlb_one_kernel(addr); flush_tlb_one_kernel() -> flush_tlb_one_user() -> __flush_tlb_one_user() -> native_flush_tlb_one_user() only flushes on the local CPU core, not on others. If you want to leave it this way, I think this needs a comment explaining why we're not doing a global flush (locking context / performance overhead / ... ?). _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel