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=-4.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, 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 CAB93C433DB for ; Tue, 2 Feb 2021 14:25:57 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 8439564E2B for ; Tue, 2 Feb 2021 14:25:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8439564E2B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=ACULAB.COM Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:In-Reply-To:References:Message-ID:Date: Subject:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=ItzCEz9RaTjxENeOA1A7jJ4uzsmJXoBAFXFa98hEe3g=; b=B0Uzjb/EfxW+cz+339DVjiF6O XSt8+Yyzmr0398aHbbeLCKzpWCPs31gIbkPdcZigy28kn4IYf0To40XwHo0OfwfuTkEALugVHcP57 m5F+4DP5UEx3Z57Pk4CCrq7Lta+RudaHrEuiBot7pt9xMVVWyElyfZ2HaLOTDBXKw6LT1sKFNtSVv K0FyTc3CrHPdihKlcrdCwvtRGiGW5N9SHHECUBAEU3dyBavLcZ2/dQHf5TbyDZQLr/Sg/e2OBjPHe 1CcdCirdh+6guwTksKJ4oiBrokGgsWlf+7qZMReV2iZCWXGzTvbSiuObLm3Ta1fdoRRz0NTBVg0eM pUX0VabwQ==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1l6wbk-0000bH-Ix; Tue, 02 Feb 2021 14:24:44 +0000 Received: from eu-smtp-delivery-151.mimecast.com ([207.82.80.151]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1l6wbh-0000aH-P1 for linux-arm-kernel@lists.infradead.org; Tue, 02 Feb 2021 14:24:43 +0000 Received: from AcuMS.aculab.com (156.67.243.126 [156.67.243.126]) (Using TLS) by relay.mimecast.com with ESMTP id uk-mta-274-flNrt4sAPICkZEemnUm5Og-1; Tue, 02 Feb 2021 14:24:34 +0000 X-MC-Unique: flNrt4sAPICkZEemnUm5Og-1 Received: from AcuMS.Aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) by AcuMS.aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Tue, 2 Feb 2021 14:24:32 +0000 Received: from AcuMS.Aculab.com ([fe80::43c:695e:880f:8750]) by AcuMS.aculab.com ([fe80::43c:695e:880f:8750%12]) with mapi id 15.00.1347.000; Tue, 2 Feb 2021 14:24:32 +0000 From: David Laight To: 'Josh Poimboeuf' , Nick Desaulniers Subject: RE: [RFC PATCH 12/17] gcc-plugins: objtool: Add plugin to detect switch table on arm64 Thread-Topic: [RFC PATCH 12/17] gcc-plugins: objtool: Add plugin to detect switch table on arm64 Thread-Index: AQHW+Pb1TwqrTbfiDUONrIh7m3kiG6pE6I/Q Date: Tue, 2 Feb 2021 14:24:32 +0000 Message-ID: <7c14b5b8b11241cd8271ba5b3f785c51@AcuMS.aculab.com> References: <20210120173800.1660730-13-jthierry@redhat.com> <20210127221557.1119744-1-ndesaulniers@google.com> <20210127232651.rj3mo7c2oqh4ytsr@treble> <20210201214423.dhsma73k7ccscovm@treble> <20210202000203.rk7lh5mx4aflgkwr@treble> In-Reply-To: <20210202000203.rk7lh5mx4aflgkwr@treble> Accept-Language: en-GB, en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] MIME-Version: 1.0 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=C51A453 smtp.mailfrom=david.laight@aculab.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: aculab.com Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210202_092441_995447_58F415B6 X-CRM114-Status: GOOD ( 11.44 ) 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 , Bill Wendling , linux-efi , Julien Thierry , clang-built-linux , Peter Zijlstra , Catalin Marinas , Masahiro Yamada , LKML , Michal Marek , "raphael.gault@arm.com" , Mark Brown , "linux-hardening@vger.kernel.org" , Will Deacon , Ard Biesheuvel , Linux ARM , Kees Cook 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 Stirring more goop into the hole .... Requiring gcc-plugins, matching compiler versions and the same 'dwarf' format for OOT modules is probably very painful. In many cases (and this may include drivers released by some distributions) an OOT driver has two separate parts. One part is C source that is compiled when the module is built on the target system and against the installed kernel headers. Getting this to match 'just' relies on having the correct compiler (etc) installed and in $PATH. The second part is much more problematic. This is just an object file compiled by a third party. It doesn't directly depend on anything defined in the kernel headers - so can (currently) be linked into any kernel version. In the past some graphics drivers have had a third party object file. I think some of the laptop wifi drivers might as well. Now I some people think everything should be free source. But there are various commercial and practical reasons for both OOT drivers and object file 'blobs' in OOT drivers. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales) _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel