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=-8.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 4C2A0CA9EAE for ; Tue, 29 Oct 2019 20:35:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1D30E21479 for ; Tue, 29 Oct 2019 20:35:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="XRKGIdWY" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727847AbfJ2Ufz (ORCPT ); Tue, 29 Oct 2019 16:35:55 -0400 Received: from mail-pl1-f196.google.com ([209.85.214.196]:40953 "EHLO mail-pl1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725840AbfJ2Ufz (ORCPT ); Tue, 29 Oct 2019 16:35:55 -0400 Received: by mail-pl1-f196.google.com with SMTP id p5so3076808plr.7 for ; Tue, 29 Oct 2019 13:35:54 -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=weRnPR6zYa479NAUpF9JwnzdoXArAq5BeasxBvL84nU=; b=XRKGIdWYXO3m1hY8XbcF6besNQxUfY5HowLorvgI06Il0r949+pXWQMiusqg7NW4bL n2NNmRL5tJyfSXfLwXr7irLEBpOMOdlwG+QXG7l00owKxPoCqxcVFS0Co7+QZnEhVhrx 8hiqpPhiSobeO+7koU+UUdkIE7/OsB5eKgyfPEVzdKPlXsOqaBn4iJSkUSLvWYoQRQxk Si4ZeOrG1j0q/fl6GMEuuIYbz7P9KayVlQXJtPP+aorYT7EgrEvU87GvMYFOphF00Zmr DOXx0aTrS6kWE9mtAAA1s6aRq1rObI7RobGaMi6KzHKBxk/qXKTL4MMQ3U1t5+oBZe1Y +2PA== 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=weRnPR6zYa479NAUpF9JwnzdoXArAq5BeasxBvL84nU=; b=pv3pH1Wma4mUUSEsc0j8dXzJOkRCs5RwoHMAwFVR9CBXZAFuop2p4NgcFVu6xkf9ZX Wzg1OZXGuZFyC00A1Bqwkwph6tiSu9423Esu2d2gplxtLMzZJjhAPkO++BC8jGePA8PL rkOEszFYh87ifI08xdWdhJqs9InLXMwPT9eGrYliFbQO/mTHS+xYwW0TzcgJbxi56R51 EbIb3lvTBDbraVkoUCJ5WJsSV/957NxK5X/MDLtx/S3hGlfxspwCNZvQ1mKQfK6SYYHx Ek9gwZ3kZ+G7eakPkjR3A7QfSKCkpHbNYx3V/ie/G8MlpN7DRP8ksmGp2bvzHqBYIx5B 31fw== X-Gm-Message-State: APjAAAUKbLGmyF1ZCl5cndAXX6oLMfT/g9hRghbXrjImZrRHqlmAOwzg Xj9dCsFHD5rhn++FZGmqJKwtwS52KQg5xwpLwhe0Qw== X-Google-Smtp-Source: APXvYqw1QuYaZCWaZyhSYUpbUd82Cb158qMxFhGB8aJGfza75ZBKXzYxqXPG4i32Epk41OS84e6p4SgzgoHmtzZc06g= X-Received: by 2002:a17:902:9b83:: with SMTP id y3mr579601plp.179.1572381353386; Tue, 29 Oct 2019 13:35:53 -0700 (PDT) MIME-Version: 1.0 References: <20191018161033.261971-1-samitolvanen@google.com> <20191024225132.13410-1-samitolvanen@google.com> <20191024225132.13410-10-samitolvanen@google.com> <20191025110313.GE40270@lakrids.cambridge.arm.com> In-Reply-To: From: Nick Desaulniers Date: Tue, 29 Oct 2019 13:35:40 -0700 Message-ID: Subject: Re: [PATCH v2 09/17] arm64: disable function graph tracing with SCS To: Mark Rutland , Kristof Beyls Cc: Will Deacon , Catalin Marinas , Steven Rostedt , Masami Hiramatsu , Ard Biesheuvel , Dave Martin , Kees Cook , Laura Abbott , Jann Horn , Miguel Ojeda , Masahiro Yamada , clang-built-linux , Kernel Hardening , linux-arm-kernel , LKML , Sami Tolvanen 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 Tue, Oct 29, 2019 at 10:45 AM Sami Tolvanen wrote: > > On Fri, Oct 25, 2019 at 4:03 AM Mark Rutland wrote: > > We have a similar issue with pointer authentication, and we're solving > > that with -fpatchable-function-entry, which allows us to hook the > > callsite before it does anything with the return address. IIUC we could > > use the same mechanism here (and avoid introducing a third). > > > > Are there plans to implement -fpatchable-function-entry on the clang > > side? > > I'm not sure if there are plans at the moment, but if this feature is > needed for PAC, adding it to clang shouldn't be a problem. Nick, did > you have any thoughts on this? I didn't see anything explicitly in LLVM's issue tracker. I also didn't see -fpatchable-function-entry currently in -next other than under arch/parisc. Are there patches I can look at? Has ARM's kernel team expressed the need to ARM's LLVM team? -- Thanks, ~Nick Desaulniers 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=-0.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_ADSP_CUSTOM_MED,DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 BCDF9CA9EAE for ; Tue, 29 Oct 2019 20:36:01 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8D0E1208E3 for ; Tue, 29 Oct 2019 20:36:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="FOp09RXF"; 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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=weRnPR6zYa479NAUpF9JwnzdoXArAq5BeasxBvL84nU=; b=T5Kx0evMazE6dH+zqgJ34beYPDG6QEvUwFRlhJfFayIbeM1IL8xj9FOD+btGiyCoCt fACMA4ICE1Z2qez7fY6jZXHc+8JDUBTMaNg3WOWYv7zgOZqd7YVapXIH1fDMlWHSYRtN i53OJME0goNTztKlj0FvDq4MPpKcktBP6mEcRKl2jKLEvWHcgpOtedivbf4IfotdWKDv iZd1tbKsgDlGBCiVb3bB3SmIKQZH08UUqw8CCXV/hQwdPtybPX1kzJMTiqKqNz5wJOrj o0DKpUW4HvzK8LdGhN0UgrbhOi6wDue+pGR7ju5UAin0SXsLMLQhJOWAKWkuwNdJbWfX H2LA== X-Gm-Message-State: APjAAAWQfuGosWmI7bn35fMGMysLX4P+DcAdx0mXkRMGh5ZtkADsLtHa effEeMJRoRTcFt030r73H3qf2tlMJwChakNCMPdnNg== X-Google-Smtp-Source: APXvYqw1QuYaZCWaZyhSYUpbUd82Cb158qMxFhGB8aJGfza75ZBKXzYxqXPG4i32Epk41OS84e6p4SgzgoHmtzZc06g= X-Received: by 2002:a17:902:9b83:: with SMTP id y3mr579601plp.179.1572381353386; Tue, 29 Oct 2019 13:35:53 -0700 (PDT) MIME-Version: 1.0 References: <20191018161033.261971-1-samitolvanen@google.com> <20191024225132.13410-1-samitolvanen@google.com> <20191024225132.13410-10-samitolvanen@google.com> <20191025110313.GE40270@lakrids.cambridge.arm.com> In-Reply-To: From: Nick Desaulniers Date: Tue, 29 Oct 2019 13:35:40 -0700 Message-ID: Subject: Re: [PATCH v2 09/17] arm64: disable function graph tracing with SCS To: Mark Rutland , Kristof Beyls X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191029_133557_894165_3E91BB55 X-CRM114-Status: GOOD ( 15.58 ) 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: Kees Cook , Ard Biesheuvel , Masahiro Yamada , Catalin Marinas , Jann Horn , LKML , Steven Rostedt , Miguel Ojeda , Masami Hiramatsu , Sami Tolvanen , clang-built-linux , Kernel Hardening , Laura Abbott , Will Deacon , Dave Martin , linux-arm-kernel Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Oct 29, 2019 at 10:45 AM Sami Tolvanen wrote: > > On Fri, Oct 25, 2019 at 4:03 AM Mark Rutland wrote: > > We have a similar issue with pointer authentication, and we're solving > > that with -fpatchable-function-entry, which allows us to hook the > > callsite before it does anything with the return address. IIUC we could > > use the same mechanism here (and avoid introducing a third). > > > > Are there plans to implement -fpatchable-function-entry on the clang > > side? > > I'm not sure if there are plans at the moment, but if this feature is > needed for PAC, adding it to clang shouldn't be a problem. Nick, did > you have any thoughts on this? I didn't see anything explicitly in LLVM's issue tracker. I also didn't see -fpatchable-function-entry currently in -next other than under arch/parisc. Are there patches I can look at? Has ARM's kernel team expressed the need to ARM's LLVM team? -- Thanks, ~Nick Desaulniers _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel 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=-8.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 0C073CA9EAE for ; Tue, 29 Oct 2019 20:36:15 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 4483B208E3 for ; Tue, 29 Oct 2019 20:36:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="XRKGIdWY" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4483B208E3 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-17151-kernel-hardening=archiver.kernel.org@lists.openwall.com Received: (qmail 21588 invoked by uid 550); 29 Oct 2019 20:36:06 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Received: (qmail 21570 invoked from network); 29 Oct 2019 20:36:06 -0000 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=weRnPR6zYa479NAUpF9JwnzdoXArAq5BeasxBvL84nU=; b=XRKGIdWYXO3m1hY8XbcF6besNQxUfY5HowLorvgI06Il0r949+pXWQMiusqg7NW4bL n2NNmRL5tJyfSXfLwXr7irLEBpOMOdlwG+QXG7l00owKxPoCqxcVFS0Co7+QZnEhVhrx 8hiqpPhiSobeO+7koU+UUdkIE7/OsB5eKgyfPEVzdKPlXsOqaBn4iJSkUSLvWYoQRQxk Si4ZeOrG1j0q/fl6GMEuuIYbz7P9KayVlQXJtPP+aorYT7EgrEvU87GvMYFOphF00Zmr DOXx0aTrS6kWE9mtAAA1s6aRq1rObI7RobGaMi6KzHKBxk/qXKTL4MMQ3U1t5+oBZe1Y +2PA== 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=weRnPR6zYa479NAUpF9JwnzdoXArAq5BeasxBvL84nU=; b=EWARHbiDYvgVT9TcaeB7W/MHITiE/uqCUk6o1xIVE6aTmahlEso+alBrAjqDcnLdjM eM2R6qOre2RzGiOnguOgVj/kO5c2h9eDhDWChI08fvmmhycPZqNTKGwY8k84J+DFP27Y 5aIK622rIZXySVP/eZ66ejB4fvgKB93w2lKz1UNh4z+cVQ2ReJBwaD6t5iNGv1Y2cmvr 2cMjRUY/uEPw5M5cJIuy/a50NxhaWwQ0TIlZEAQ2o3NZjbk9SfclwT3Kkopuhch5WM9m 4Ehl4FLuLRSb6d0p1L+p+voiRRDaYcPCAl0R/AjV5MPDrAdsmoJdo1CdBaMukGFFX+kk kqeQ== X-Gm-Message-State: APjAAAVcdczyg/JEH/8qeOpSjbnJr7y3UBN/eITL7CbrUTszisorcos2 vhGHXOsO8du71SYZhhc5/yPUTypYsUzKLnDHFnpNJg== X-Google-Smtp-Source: APXvYqw1QuYaZCWaZyhSYUpbUd82Cb158qMxFhGB8aJGfza75ZBKXzYxqXPG4i32Epk41OS84e6p4SgzgoHmtzZc06g= X-Received: by 2002:a17:902:9b83:: with SMTP id y3mr579601plp.179.1572381353386; Tue, 29 Oct 2019 13:35:53 -0700 (PDT) MIME-Version: 1.0 References: <20191018161033.261971-1-samitolvanen@google.com> <20191024225132.13410-1-samitolvanen@google.com> <20191024225132.13410-10-samitolvanen@google.com> <20191025110313.GE40270@lakrids.cambridge.arm.com> In-Reply-To: From: Nick Desaulniers Date: Tue, 29 Oct 2019 13:35:40 -0700 Message-ID: Subject: Re: [PATCH v2 09/17] arm64: disable function graph tracing with SCS To: Mark Rutland , Kristof Beyls Cc: Will Deacon , Catalin Marinas , Steven Rostedt , Masami Hiramatsu , Ard Biesheuvel , Dave Martin , Kees Cook , Laura Abbott , Jann Horn , Miguel Ojeda , Masahiro Yamada , clang-built-linux , Kernel Hardening , linux-arm-kernel , LKML , Sami Tolvanen Content-Type: text/plain; charset="UTF-8" On Tue, Oct 29, 2019 at 10:45 AM Sami Tolvanen wrote: > > On Fri, Oct 25, 2019 at 4:03 AM Mark Rutland wrote: > > We have a similar issue with pointer authentication, and we're solving > > that with -fpatchable-function-entry, which allows us to hook the > > callsite before it does anything with the return address. IIUC we could > > use the same mechanism here (and avoid introducing a third). > > > > Are there plans to implement -fpatchable-function-entry on the clang > > side? > > I'm not sure if there are plans at the moment, but if this feature is > needed for PAC, adding it to clang shouldn't be a problem. Nick, did > you have any thoughts on this? I didn't see anything explicitly in LLVM's issue tracker. I also didn't see -fpatchable-function-entry currently in -next other than under arch/parisc. Are there patches I can look at? Has ARM's kernel team expressed the need to ARM's LLVM team? -- Thanks, ~Nick Desaulniers