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=-7.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 54EFEC433ED for ; Fri, 9 Apr 2021 11:57:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2D16461178 for ; Fri, 9 Apr 2021 11:57:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233426AbhDIL5l (ORCPT ); Fri, 9 Apr 2021 07:57:41 -0400 Received: from mail.kernel.org ([198.145.29.99]:51472 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231611AbhDIL5k (ORCPT ); Fri, 9 Apr 2021 07:57:40 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id ABD266115B; Fri, 9 Apr 2021 11:57:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1617969447; bh=xWpZMs8SF1KeRP75gFOHcEWwPPGqR29BI1NfJEUZSpM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=p5nvaFt2mOhhxiQsclwdeybVrho712FuWXR+NV8KhOzB2O7xRD4wLfZHp4HgW3ypz h6y1CTRkgOerE2hXcrD9b6oXIUxy4NRLcPnhmzkxyfix2DIFv2d9z/20+3QwcB7uTF j6QHEE7lXRZkW8rU7pVWXcyRBwFxUduEJ1uyGcwfevQISRDSN++5xjTdu7G6a0a7Zm JiSaOVX+TTq5oUkdkA/QsRSxqfP6E5paBUgkm0J6wGGead2CHJkVWACA2ValNdbUVW 875sa8vPjaBibm7/DvjjFV5ZVwbB7RXDXWSTa1yv2xgI1BnkXF8DgpsRDIgHnSulfH jaNIv44yfKZsw== Date: Fri, 9 Apr 2021 12:57:08 +0100 From: Mark Brown To: "Madhavan T. Venkataraman" Cc: mark.rutland@arm.com, jpoimboe@redhat.com, jthierry@redhat.com, catalin.marinas@arm.com, will@kernel.org, linux-arm-kernel@lists.infradead.org, live-patching@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH v2 1/4] arm64: Implement infrastructure for stack trace reliability checks Message-ID: <20210409115708.GB4499@sirena.org.uk> References: <705993ccb34a611c75cdae0a8cb1b40f9b218ebd> <20210405204313.21346-1-madvenka@linux.microsoft.com> <20210405204313.21346-2-madvenka@linux.microsoft.com> <20210408171715.GQ4516@sirena.org.uk> <69b6924b-88f6-6c40-7b18-8cdf15d92bd1@linux.microsoft.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="GID0FwUMdk1T2AWN" Content-Disposition: inline In-Reply-To: X-Cookie: Ring around the collar. User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --GID0FwUMdk1T2AWN Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Thu, Apr 08, 2021 at 06:30:22PM -0500, Madhavan T. Venkataraman wrote: > On 4/8/21 2:30 PM, Madhavan T. Venkataraman wrote: > > 1. Create a common section (I will have to come up with an appropriate name) and put > > all such functions in that one section. > > 2. Create one section for each logical type (exception section, ftrace section and > > kprobe section) or some such. > For now, I will start with idea 2. I will create a special section for each class of > functions (EL1 exception handlers, FTRACE trampolines, KPROBE trampolines). Instead of a > special functions array, I will implement a special_sections array. The rest of the code > should just fall into place. > Let me know if you prefer something different. It might be safer to start off by just putting all SYM_CODE into a section then pulling bits we know to be safe out of the section as needed - we know that anything that's SYM_CODE is doing something non-standard and needs checking to verify that the unwinder will be happy with it and I that should cover most if not all of the cases above as well as anything else we didn't explicitly think of. --GID0FwUMdk1T2AWN Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAmBwQRMACgkQJNaLcl1U h9CDkAf+M7uGGOV6l9nKclvAJwd8o31oulE0GngUxx7kQvOsTZvVfWVJOR921/x/ 42gh2W7vxL7LOfQ37vMafyz3BtoO+aX29aRSfSfqskqufOk4KmbqZ2YmMTs5iiwy r8Dr0POZ9NYuie7+f+aYLbYaLBStriNn6VamKJlomBaXmiZdvsEmmif8IrjrLLnR Sz6+G0qFRd6VK30NB0dbpjLQzzHFDN8gc0IpPjmgSMysz+/Oe8XqGgdhq6Xti6Bl T/A/VeO/+E3xDTwIooXm0pk95tRg8ef+gmYpFi01C63F6zEUk7/frUC/g0VZGzPL 7lxu5UFkpo8Bi9bvHxhk6LaTXjMAxw== =y0XZ -----END PGP SIGNATURE----- --GID0FwUMdk1T2AWN--