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=-3.8 required=3.0 tests=BAYES_00, 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 BC430C433E0 for ; Mon, 15 Feb 2021 10:24:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 78F8E64E27 for ; Mon, 15 Feb 2021 10:24:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229943AbhBOKYE (ORCPT ); Mon, 15 Feb 2021 05:24:04 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57576 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229627AbhBOKYB (ORCPT ); Mon, 15 Feb 2021 05:24:01 -0500 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 891A3C061756 for ; Mon, 15 Feb 2021 02:23:20 -0800 (PST) Received: from gallifrey.ext.pengutronix.de ([2001:67c:670:201:5054:ff:fe8d:eefb] helo=[IPv6:::1]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lBb2C-0002vs-Le; Mon, 15 Feb 2021 11:23:16 +0100 Message-ID: <188afd4d2e299652da33ad5d4ea743f02fb2ffc5.camel@pengutronix.de> Subject: Re: [PATCH] kernel: Expose SYS_kcmp by default From: Lucas Stach To: Pavel Machek , Chris Wilson Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, Kees Cook , Andy Lutomirski , Will Drewry , Andrew Morton , Dave Airlie , Daniel Vetter Date: Mon, 15 Feb 2021 11:23:11 +0100 In-Reply-To: <20210213174000.GA31409@duo.ucw.cz> References: <20210205163752.11932-1-chris@chris-wilson.co.uk> <20210213174000.GA31409@duo.ucw.cz> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.38.3 (3.38.3-1.fc33) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 2001:67c:670:201:5054:ff:fe8d:eefb X-SA-Exim-Mail-From: l.stach@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am Samstag, dem 13.02.2021 um 18:40 +0100 schrieb Pavel Machek: > Hi! > > > Userspace has discovered the functionality offered by SYS_kcmp and has > > started to depend upon it. In particular, Mesa uses SYS_kcmp for > > os_same_file_description() in order to identify when two fd (e.g. device > > or dmabuf) point to the same struct file. Since they depend on it for > > core functionality, lift SYS_kcmp out of the non-default > > CONFIG_CHECKPOINT_RESTORE into the selectable syscall category. > > Is it good idea to enable everything because Mesa uses it for file > descriptors? > > This is really interesting syscall... As Debian/Ubuntu and Fedora are already shipping with CONFIG_CHECKPOINT_RESTORE=y in their kernel configs, I don't really see the need to add further restrictions here. Or this discussion should have happened a while ago... Regards, Lucas