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=-4.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 25B2AC433DF for ; Thu, 16 Jul 2020 07:58:19 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 7B5C520775 for ; Thu, 16 Jul 2020 07:58:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="TZzTFaLg" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7B5C520775 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-19342-kernel-hardening=archiver.kernel.org@lists.openwall.com Received: (qmail 22089 invoked by uid 550); 16 Jul 2020 07:58:11 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Received: (qmail 22051 invoked from network); 16 Jul 2020 07:58:10 -0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=GFw2paDr6x0B7btxhYa6Jgza9jDSX5w0Syg6HAfqvAU=; b=TZzTFaLgoCrDFyD2Ef7BIGlBta PcBSBGGB+L1ZGg/6TvwqEVkDwtJvPMwytSYQGDp70iFs3HYFtUzixiCUJBCw87DTMJBfIXHnvvfnd 6ameDw70kTnMCMShOJMLxtGhSyz6kY4hrpUUBjp0ui+1HVAj0Hay4YgN/lD2M/s7p7WsPZX2sJgpx m0smx2K4jAlv5k8raCR6nfmWAqaiI+XQ35t9LL9ZDp7G/Bd6Xv6xN/1+oU2M1YPrCDGAKZNt5KRft m+Xhvn6+OLAoQcGmFJfkRhrkSCPQ3enbR99hEbretKEtzPoWiv9AHO8kAFyBzSXUqnNW18hpG0dgz Y6UHjSQA==; Date: Thu, 16 Jul 2020 09:57:18 +0200 From: Peter Zijlstra To: Kees Cook Cc: Greg Kroah-Hartman , Thomas Gleixner , Allen Pais , Oscar Carter , Romain Perier , Dmitry Torokhov , Kevin Curtis , "David S. Miller" , Jakub Kicinski , Harald Freudenberger , Heiko Carstens , Vasily Gorbik , Christian Borntraeger , Jiri Slaby , Felipe Balbi , Jason Wessel , Daniel Thompson , Douglas Anderson , Mitchell Blank Jr , Julian Wiedmann , Karsten Graul , Ursula Braun , Jaroslav Kysela , Takashi Iwai , Christian Gromm , Nishka Dasgupta , Masahiro Yamada , Stephen Boyd , "Matthew Wilcox (Oracle)" , Wambui Karuga , Guenter Roeck , Chris Packham , Kyungtae Kim , Kuppuswamy Sathyanarayanan , Sebastian Andrzej Siewior , "Rafael J. Wysocki" , Jonathan Corbet , Will Deacon , linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, linux-s390@vger.kernel.org, devel@driverdev.osuosl.org, linux-usb@vger.kernel.org, kgdb-bugreport@lists.sourceforge.net, alsa-devel@alsa-project.org, kernel-hardening@lists.openwall.com Subject: Re: [PATCH 0/3] Modernize tasklet callback API Message-ID: <20200716075718.GM10769@hirez.programming.kicks-ass.net> References: <20200716030847.1564131-1-keescook@chromium.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200716030847.1564131-1-keescook@chromium.org> On Wed, Jul 15, 2020 at 08:08:44PM -0700, Kees Cook wrote: > Hi, > > This is the infrastructure changes to prepare the tasklet API for > conversion to passing the tasklet struct as the callback argument instead > of an arbitrary unsigned long. The first patch details why this is useful > (it's the same rationale as the timer_struct changes from a bit ago: > less abuse during memory corruption attacks, more in line with existing > ways of doing things in the kernel, save a little space in struct, > etc). Notably, the existing tasklet API use is much less messy, so there > is less to clean up. I would _MUCH_ rather see tasklets go the way of the dodo, esp. given that: > drivers/input/keyboard/omap-keypad.c | 2 +- > drivers/input/serio/hil_mlc.c | 2 +- > drivers/net/wan/farsync.c | 4 +-- > drivers/s390/crypto/ap_bus.c | 2 +- > drivers/staging/most/dim2/dim2.c | 2 +- > drivers/staging/octeon/ethernet-tx.c | 2 +- > drivers/tty/vt/keyboard.c | 2 +- > drivers/usb/gadget/udc/snps_udc_core.c | 6 ++--- > drivers/usb/host/fhci-sched.c | 2 +- > include/linux/interrupt.h | 37 ++++++++++++++++++++++---- > kernel/backtracetest.c | 2 +- > kernel/debug/debug_core.c | 2 +- > kernel/irq/resend.c | 2 +- > kernel/softirq.c | 18 ++++++++++++- > net/atm/pppoatm.c | 2 +- > net/iucv/iucv.c | 2 +- > sound/drivers/pcsp/pcsp_lib.c | 2 +- > 17 files changed, 66 insertions(+), 25 deletions(-) there appear to be hardly any users left.. Can't we stage an extinction event here instead?