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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 27106E74903 for ; Tue, 3 Oct 2023 16:55:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240593AbjJCQzg (ORCPT ); Tue, 3 Oct 2023 12:55:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47654 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240501AbjJCQzf (ORCPT ); Tue, 3 Oct 2023 12:55:35 -0400 Received: from wout4-smtp.messagingengine.com (wout4-smtp.messagingengine.com [64.147.123.20]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B5C2ED7; Tue, 3 Oct 2023 09:55:24 -0700 (PDT) Received: from compute5.internal (compute5.nyi.internal [10.202.2.45]) by mailout.west.internal (Postfix) with ESMTP id 70DFF3200B6E; Tue, 3 Oct 2023 12:55:22 -0400 (EDT) Received: from imap51 ([10.202.2.101]) by compute5.internal (MEProxy); Tue, 03 Oct 2023 12:55:24 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arndb.de; h=cc :cc:content-type:content-type:date:date:from:from:in-reply-to :in-reply-to:message-id:mime-version:references:reply-to:sender :subject:subject:to:to; s=fm1; t=1696352121; x=1696438521; bh=bM N3ahYNWDfnd39aNSh3WGWAh25s8Cnm4TD3ZVFC+Qc=; b=We9PtvKNlGv7dvx37W gvw7JROLcaGwJW81HX+bOX0v2ZSUP/FkK60Nja7JSezA8Ob2D0JJaM7KQC/4B6dg 3FkAc8zXsJvBYYrEiEGhlts0rBcAQBkEEkZxcRD8wblX+A+aVbt0zSkJeOlrXFgi dN7ZDRXkZlF1ngYu9L3h3KTZz5wgJT15OaClA6MhdE+Ie2/n9E4FdAEqBCke7V45 qgCQglaN5c/rDOtC4r/ZFMPK1B8A74TPfSdNjeAAtBOx42ADjrvDSWXND2UhaJYD 5YvLx9+ARgBv0tNv8EitzYh4jhk3nwcKhWO2EtFf3FYOQpe+Kzwo0886VIYCSSak FbiQ== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-type:content-type:date:date :feedback-id:feedback-id:from:from:in-reply-to:in-reply-to :message-id:mime-version:references:reply-to:sender:subject :subject:to:to:x-me-proxy:x-me-proxy:x-me-sender:x-me-sender :x-sasl-enc; s=fm2; t=1696352121; x=1696438521; bh=bMN3ahYNWDfnd 39aNSh3WGWAh25s8Cnm4TD3ZVFC+Qc=; b=edST69BZgCUs+ZJ5Nwm6y0b6a7XVj LnT6QaEQ1fCdfOq8oJrgP+uusP0BOtTgrKIYuWxLUTxC9bJzfbgS+bOwL8TkPZ8n gzUIAj61U8YvG4zqACt88GvvJWIHP2aWutbDQ8lpMTCxocYi7tD7Rn5MA0+5no+O 4vmTwvg32YQPkeWZIBdyj8xBY/Emsv1vpyJA73bIy+cjoWSq9VVwuegpBMEIkwY7 2G6ULyIH236et9sQ5eRKYfYs9ktCxNHMF6sR8Sx3PEIPcaCOLvFoJ5UWS/szXZB/ 6SR7SQ+60qLHjSOD8gR/StWwKTyRCCGoLP9UjNXJtYiixRKvOkDMWAG5w== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvkedrfeejgdduhecutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenuc fjughrpefofgggkfgjfhffhffvvefutgesthdtredtreertdenucfhrhhomhepfdetrhhn ugcuuegvrhhgmhgrnhhnfdcuoegrrhhnugesrghrnhgusgdruggvqeenucggtffrrghtth gvrhhnpeevhfffledtgeehfeffhfdtgedvheejtdfgkeeuvefgudffteettdekkeeufeeh udenucffohhmrghinhepkhgvrhhnvghlrdhorhhgnecuvehluhhsthgvrhfuihiivgeptd enucfrrghrrghmpehmrghilhhfrhhomheprghrnhgusegrrhhnuggsrdguvg X-ME-Proxy: Feedback-ID: i56a14606:Fastmail Received: by mailuser.nyi.internal (Postfix, from userid 501) id 48524B60089; Tue, 3 Oct 2023 12:55:21 -0400 (EDT) X-Mailer: MessagingEngine.com Webmail Interface User-Agent: Cyrus-JMAP/3.9.0-alpha0-958-g1b1b911df8-fm-20230927.002-g1b1b911d MIME-Version: 1.0 Message-Id: <231994b0-ca11-4347-8d93-ce66fdbe3d25@app.fastmail.com> In-Reply-To: <487836fc-7c9f-2662-66a4-fa5e3829cf6b@intel.com> References: <20230914185804.2000497-1-sohil.mehta@intel.com> <487836fc-7c9f-2662-66a4-fa5e3829cf6b@intel.com> Date: Tue, 03 Oct 2023 18:54:59 +0200 From: "Arnd Bergmann" To: "Sohil Mehta" , linux-api@vger.kernel.org, Linux-Arch Cc: "Richard Henderson" , "Ivan Kokshaysky" , "Matt Turner" , "Russell King" , "Catalin Marinas" , "Will Deacon" , "Geert Uytterhoeven" , "Michal Simek" , "Thomas Bogendoerfer" , "James E . J . Bottomley" , "Helge Deller" , "Michael Ellerman" , "Nicholas Piggin" , "Christophe Leroy" , "Heiko Carstens" , "Vasily Gorbik" , "Alexander Gordeev" , "Christian Borntraeger" , "Sven Schnelle" , "Yoshinori Sato" , "Rich Felker" , "John Paul Adrian Glaubitz" , "David S . Miller" , "Andy Lutomirski" , "Thomas Gleixner" , "Ingo Molnar" , "Borislav Petkov" , "Dave Hansen" , x86@kernel.org, "H. Peter Anvin" , "Chris Zankel" , "Max Filippov" , "Peter Zijlstra" , "Arnaldo Carvalho de Melo" , "Mark Rutland" , "Alexander Shishkin" , "Jiri Olsa" , "Namhyung Kim" , "Ian Rogers" , "Adrian Hunter" , "Lukas Bulwahn" , "Sergei Trofimovich" , "Andrew Morton" , "Rohan McLure" , "Andreas Schwab" , "Eric W. Biederman" , "Brian Gerst" , "Randy Dunlap" , "Rick Edgecombe" , "Mark Brown" , "Deepak Gupta" , linux-alpha@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-perf-users@vger.kernel.org Subject: Re: [PATCH v2] arch: Reserve map_shadow_stack() syscall number for all architectures Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-api@vger.kernel.org On Tue, Oct 3, 2023, at 18:35, Sohil Mehta wrote: > On 9/14/2023 11:58 AM, Sohil Mehta wrote: >> commit c35559f94ebc ("x86/shstk: Introduce map_shadow_stack syscall") >> recently added support for map_shadow_stack() but it is limited to x86 >> only for now. There is a possibility that other architectures (namely, >> arm64 and RISC-V), that are implementing equivalent support for shadow >> stacks, might need to add support for it. >> >> Independent of that, reserving arch-specific syscall numbers in the >> syscall tables of all architectures is good practice and would help >> avoid future conflicts. map_shadow_stack() is marked as a conditional >> syscall in sys_ni.c. Adding it to the syscall tables of other >> architectures is harmless and would return ENOSYS when exercised. >> >> Note, map_shadow_stack() was assigned #453 during the merge process >> since #452 was taken by fchmodat2(). >> >> For Powerpc, map it to sys_ni_syscall() as is the norm for Powerpc >> syscall tables. >> >> For Alpha, map_shadow_stack() takes up #563 as Alpha still diverges from >> the common syscall numbering system in the other architectures. >> >> Link: https://lore.kernel.org/lkml/20230515212255.GA562920@debug.ba.rivosinc.com/ >> Link: https://lore.kernel.org/lkml/b402b80b-a7c6-4ef0-b977-c0f5f582b78a@sirena.org.uk/ >> >> Signed-off-by: Sohil Mehta >> --- > > Gentle ping... > > Are there any additional comments? It applies cleanly on 6.6-rc4. > > Or does it seem ready to be merged? It has the following > acknowledgements until now: > > Reviewed-by: Rick Edgecombe > Acked-by: Michael Ellerman (powerpc) > Reviewed-by: Arnd Bergmann If you like, I can pick this up for 6.7 through the asm-generic tree. If you think this should be part of 6.6, I would suggest to merge it through the tree that originally contained the syscall code. Arnd