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=-3.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 CF1EDC433B4 for ; Fri, 14 May 2021 03:23:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 93B1F6143E for ; Fri, 14 May 2021 03:23:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231609AbhENDYt (ORCPT ); Thu, 13 May 2021 23:24:49 -0400 Received: from terminus.zytor.com ([198.137.202.136]:55575 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230202AbhENDYs (ORCPT ); Thu, 13 May 2021 23:24:48 -0400 Received: from [IPv6:2607:fb90:8499:54e2:5b10:3bfe:8ae:a691] ([IPv6:2607:fb90:8499:54e2:5b10:3bfe:8ae:a691]) (authenticated bits=0) by mail.zytor.com (8.16.1/8.15.2) with ESMTPSA id 14E3NK3j3045135 (version=TLSv1.3 cipher=TLS_AES_128_GCM_SHA256 bits=128 verify=NO); Thu, 13 May 2021 20:23:21 -0700 DKIM-Filter: OpenDKIM Filter v2.11.0 mail.zytor.com 14E3NK3j3045135 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zytor.com; s=2021042801; t=1620962602; bh=8ynf+5yIPfkNq8YcZl5TieOBXA43cui1r+6yFVD+gO8=; h=Date:In-Reply-To:References:Subject:To:CC:From:From; b=AeOEYqb9+kkf8bTzwy4w2F5d6iM2z4NizowWTSxFPH07fj5KS3w+puziaveDKXwXD /Yz7jw5ja6MlpYtIgzQquDuW2WkaQr95c16af+CtA4w6wxLL8J3Djojb9av36HbG2j UmIc1uCPHD0vWD7W0xZGDVrzP63TgD5fAx4SVdcV+OuzY6MCjD8qieBMafirxhfHG9 JxN+MSwL9kvQfpgcgv6MVs/dEWX//g6ibKzJL7DGCWaGooanNNanSE7qgAKCS1p4dH y4slwDbLP0I2X995QyLYaZiF2sRVS1G6WhrsRO9QyJcnlyv9D8PKWCbTSy6M1Xdh+x hjhTgNIoAOtBw== Date: Thu, 13 May 2021 20:23:17 -0700 User-Agent: K-9 Mail for Android In-Reply-To: <57bf2ff9-11ff-0907-975e-15177df72144@linux.luto.us> References: <871racf928.ffs@nanos.tec.linutronix.de> <60495dd3-ea68-4db3-47ad-b7b45796bf76@zytor.com> <87o8dfer7k.ffs@nanos.tec.linutronix.de> <87mtsz619u.ffs@nanos.tec.linutronix.de> <57bf2ff9-11ff-0907-975e-15177df72144@linux.luto.us> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [RFC v2 PATCH 7/7] x86/entry: use int for syscall number; handle all invalid syscall nrs To: Andy Lutomirski , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Andy Lutomirski CC: Linux Kernel Mailing List From: "H. Peter Anvin" Message-ID: <486B4C98-FFD1-40B9-B7AF-5323DE07A0FE@zytor.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Yeah=2E Also, x32 long is 32 bits=2E=2E=2E On May 13, 2021 8:18:37 PM PDT, Andy Lutomirski w= rote: >On 5/13/21 5:38 PM, H=2E Peter Anvin wrote: >> On 5/12/21 3:22 PM, Thomas Gleixner wrote: >>>> >>>> As far as this being a user ABI change, this is actually a revert >to the >>>> original x86-64 ABI; see my message to Ingo=2E >>> >>> I'm not against that change, but it has to be well justified and the >>> reasoning wants to be in the changelog=2E You know the drill :) >>> >>=20 >> FYI: >>=20 >> So in the process of breaking up and better document this patch, I >have >> looked at the syscall_numbering_64 (and have rewritten it to be more >> complete=2E) >>=20 >> I found that running it under strace fails, as strace (possibly >ptrace, >> possibly the strace binary) causes %rax =3D 2^32 to be clobbered to >zero >> already=2E=2E=2E >>=20 >> More motivation, I guess=2E >>=20 > >Indeed=2E > >I would love to go back in time and switch to long, but there are >plenty >of things that use int now=2E I suppose we could try to make it long for >real, but seccomp has u32 baked into its ABI=2E --=20 Sent from my Android device with K-9 Mail=2E Please excuse my brevity=2E