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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id F28A6D3C92D for ; Sat, 19 Oct 2024 22:30:48 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 7232D6B0089; Sat, 19 Oct 2024 18:30:48 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 6D2CC6B008A; Sat, 19 Oct 2024 18:30:48 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 59A2D6B008C; Sat, 19 Oct 2024 18:30:48 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 41F736B0089 for ; Sat, 19 Oct 2024 18:30:48 -0400 (EDT) Received: from smtpin21.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 9E302140E45 for ; Sat, 19 Oct 2024 22:30:33 +0000 (UTC) X-FDA: 82691797356.21.560DE58 Received: from nyc.source.kernel.org (nyc.source.kernel.org [147.75.193.91]) by imf06.hostedemail.com (Postfix) with ESMTP id EF7DD18000A for ; Sat, 19 Oct 2024 22:30:36 +0000 (UTC) Authentication-Results: imf06.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b="CErL8/nt"; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf06.hostedemail.com: domain of mcgrof@kernel.org designates 147.75.193.91 as permitted sender) smtp.mailfrom=mcgrof@kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1729376937; a=rsa-sha256; cv=none; b=ypYu7ajyf97GSnhqNET4q6qTTPNN16I2Oy8xhiIvIK16E6Kv757m9mRH/iICCClDAT4HUE aetwelm+l48NSi8dTQrWFIZPHTnF4eaFz45zyW1kxJx9Y2jBYMlHzvP/CoGk1Y9bsjt6r0 0XXtNgPYEwhcHmgyC73oBQWpE8WURZQ= ARC-Authentication-Results: i=1; imf06.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b="CErL8/nt"; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf06.hostedemail.com: domain of mcgrof@kernel.org designates 147.75.193.91 as permitted sender) smtp.mailfrom=mcgrof@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1729376937; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=VuHy1HrHdhUjSm/D9WaG63hW9NcA1Axd/7XrPQvY+Bo=; b=vo4wMJHkLCMzpC9yQOgAfCDMoF4EMav/S0aeIRxaUnhR9lEsCEFWkpDgUrPmRjzPfbrDFf 1aaCmyn6CLJgZV/zh0icRJqB5NFF4WFL3ekp5XoBIZ+FPHbYSjEkR+6k8lcKIpMLglUkkv zBod+F1wDj5KNfI+JCVbaJyZ7ic3VnI= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by nyc.source.kernel.org (Postfix) with ESMTP id 0111FA40448; Sat, 19 Oct 2024 22:30:35 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CF36EC4CEC5; Sat, 19 Oct 2024 22:30:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1729377044; bh=QyfIXk+096xDFBJfNhGtA+h7+x144NJyXqGZEWCxEbA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=CErL8/nta/6r/1WJkkwG/t5evnd+rztuMKPvEAcvD2SnHlbG8tiM8oebQum4YnbtM jKRTZBaC+ATcd4VCxL5682bSGxbHvqjRzPrn6cR/xecdWEBWr3gweQycvt1RfyCGs7 MiXNOy+V4Fewi4RfizJAsZmsup5CQWNXqWmaamyVMyXGW/hUqx3sW49nhqNlGd3ZzY ETj4BkT4BYSwhfn/AQ96YSvs+Sq6IlTIlZXVNMpeHMX+0ZQjv+FZRA/RKrz+t3dZ4u 1qH1N38SWuCE3fte75V0TIkKwCKF9lts668sBgQlwW5eAV1dEKJXhxg+1WEdnmmBQI jKYmcc+lcknEw== Date: Sat, 19 Oct 2024 15:30:41 -0700 From: Luis Chamberlain To: Mike Rapoport Cc: Andrew Morton , Andreas Larsson , Andy Lutomirski , Ard Biesheuvel , Arnd Bergmann , Borislav Petkov , Brian Cain , Catalin Marinas , Christoph Hellwig , Christophe Leroy , Dave Hansen , Dinh Nguyen , Geert Uytterhoeven , Guo Ren , Helge Deller , Huacai Chen , Ingo Molnar , Johannes Berg , John Paul Adrian Glaubitz , Kent Overstreet , "Liam R. Howlett" , Mark Rutland , Masami Hiramatsu , Matt Turner , Max Filippov , Michael Ellerman , Michal Simek , Oleg Nesterov , Palmer Dabbelt , Peter Zijlstra , Richard Weinberger , Russell King , Song Liu , Stafford Horne , Steven Rostedt , Suren Baghdasaryan , Thomas Bogendoerfer , Thomas Gleixner , Uladzislau Rezki , Vineet Gupta , Will Deacon , bpf@vger.kernel.org, linux-alpha@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org, linux-kernel@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-mm@kvack.org, linux-modules@vger.kernel.org, linux-openrisc@vger.kernel.org, linux-parisc@vger.kernel.org, linux-riscv@lists.infradead.org, linux-sh@vger.kernel.org, linux-snps-arc@lists.infradead.org, linux-trace-kernel@vger.kernel.org, linux-um@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, loongarch@lists.linux.dev, sparclinux@vger.kernel.org, x86@kernel.org Subject: Re: [PATCH v6 4/8] module: prepare to handle ROX allocations for text Message-ID: References: <20241016122424.1655560-1-rppt@kernel.org> <20241016122424.1655560-5-rppt@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20241016122424.1655560-5-rppt@kernel.org> X-Rspamd-Queue-Id: EF7DD18000A X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: x3nq7ezkzkh7go53m1bh7urrg1pw7sej X-HE-Tag: 1729377036-723861 X-HE-Meta: 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 goc/eDy7 TT7Qb3TzlS3vlIr6eYyoEIrVZKlyks5t4fxpkAlkZCThWqT0xc0TPorzLJb4S4vtLRJk5WtLop+vr2x49WIP2c1AHAtJl17MLDy+cpV1BAqfI8kqjMf7amvpspBjPwZxp7+c2SQQqVAR5sO0IwGGN0aicm67+r9HT0nHnKpIGXwzSNktDwD0vaxx3mBR3WogemSlwxc5OOWCmEZhBIatY+rvQlcKSjBQ6BtOt0pYi4n3GXqo= 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: List-Subscribe: List-Unsubscribe: On Wed, Oct 16, 2024 at 03:24:20PM +0300, Mike Rapoport wrote: > From: "Mike Rapoport (Microsoft)" > > In order to support ROX allocations for module text, it is necessary to > handle modifications to the code, such as relocations and alternatives > patching, without write access to that memory. > > One option is to use text patching, but this would make module loading > extremely slow and will expose executable code that is not finally formed. > > A better way is to have memory allocated with ROX permissions contain > invalid instructions and keep a writable, but not executable copy of the > module text. The relocations and alternative patches would be done on the > writable copy using the addresses of the ROX memory. > Once the module is completely ready, the updated text will be copied to ROX > memory using text patching in one go and the writable copy will be freed. > > Add support for that to module initialization code and provide necessary > interfaces in execmem. > > Signed-off-by: Mike Rapoport (Microsoft) Reviewd-by: Luis Chamberlain Luis