Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934970AbZJNQzc (ORCPT ); Wed, 14 Oct 2009 12:55:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S934954AbZJNQzb (ORCPT ); Wed, 14 Oct 2009 12:55:31 -0400 Received: from mail-fx0-f227.google.com ([209.85.220.227]:49616 "EHLO mail-fx0-f227.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934537AbZJNQza (ORCPT ); Wed, 14 Oct 2009 12:55:30 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlemail.com; s=gamma; h=from:to:subject:date:user-agent:cc:references:in-reply-to :mime-version:content-type:content-transfer-encoding:message-id; b=In7XB/UbkpAX4UIlOiL+ub8e7C8cYBww/StC0M387zTGf9/0h9vFZDoTj06a4KPo9K BEoz/VHcwd86whO0CjmkBBSA4g22wVcKwqbHGFRXXGGjtH1eEl9dyZ05a4ywllbyFxgh oDb2EqVGCnS5UQYDf9HtZhulvjs7H6vdFLW6Q= From: Arnd Bergmann To: Thomas Gleixner Subject: Re: [tip:bkl/drivers] drivers: Remove BKL from misc_open Date: Wed, 14 Oct 2009 18:54:49 +0200 User-Agent: KMail/1.12.1 (Linux/2.6.31-11-generic; KDE/4.3.1; x86_64; ; ) Cc: Alan Cox , mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, gregkh@suse.de, linux-tip-commits@vger.kernel.org References: <20091010153349.237173041@linutronix.de> <20091014171249.57dcdcfc@lxorguk.ukuu.org.uk> In-Reply-To: MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <200910141854.49418.arnd@arndb.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3075 Lines: 97 On Wednesday 14 October 2009, Thomas Gleixner wrote: > on Wed, 14 Oct 2009, Alan Cox wrote: > > You can't simply assume the mutex is enough - you have to either push it > > down or review *every* possible called point below the lock_kernel take. > > > > In this case the open method of the misc devices below sometimes uses the > > BKL. > > The BKL got pushed down into the open methods of misc dev users and we > do not need to take it twice in a row, right ? > I worked on the original pushdown back then and believed it to be complete. New drivers have come in and some obviously unneeded instances got cleared of the BKL usage. The ones with an open method that does not take the BKL are: arch/mips/basler/excite/excite_iodev.c arch/x86/kernel/apm_32.c drivers/buetooth/hci_vhci.c drivers/char/nvram.c drivers/char/rtc.c drivers/gpu/vga/vgaarb.c drivers/hwmon/fschmd.c drivers/hwmon/lis3lv02d.c drivers/infiniband/core/ucma.c drivers/isdn/mISDN/timerdev.c drivers/s390/char/vmcp.c fs/cachefiles/daemon.c fs/dlm/user.c fs/fuse/cuse.c kernel/power/user.c net/rfkill/core.c As well as some drivers from staging and watchdog. I believe the BKL usage in watchdog drivers was removed shortly after the pushdown. Arnd <>< drivers/staging/android/binder.c drivers/staging/dream/qdsp5/audio_aac.c drivers/staging/dream/qdsp5/audio_evrc.c drivers/staging/dream/qdsp5/audio_in.c drivers/staging/dream/qdsp5/audio_out.c drivers/staging/dream/qdsp5/snd.c drivers/staging/dream/smd/smd_qmi.c drivers/staging/panel/panel.c drivers/watchdog/acquirewdt.c drivers/watchdog/adx_wdt.c drivers/watchdog/alim7101_wdt.c drivers/watchdog/at32ap700x_wdt.c drivers/watchdog/at91sam9_wdt.c drivers/watchdog/fin_wdt.c drivers/watchdog/coh901327_wdt.c drivers/watchdog/ep93xx_wdt.c drivers/watchdog/gef_wdt.c drivers/watchdog/geodewdt.c drivers/watchdog/i6300esb.c drivers/watchdog/b700wwdt.c drivers/watchdog/ibmasr.c drivers/watchdog/iop_wdt.c drivers/watchdog/it8_wdt.c drivers/watchdog/ixp4xx_wdt.c drivers/watchdog/machzwd.c drivers/watchdog/mpc5200_wdt.c drivers/watchdog/mpcore_wdt.c drivers/watchdog/mv64x60_wdt.c drivers/watchdog/omap_wdt.c drivers/watchdog/pc87413_wdt.c drivers/watchdog/pcwd.c drivers/watchdog/pcwd_pci.c drivers/watchdog/pcwd_usb.c drivers/watchdog/pnx4008_wdt.c drivers/watchdog/rc32434_wdt.c drivers/watchdog/s3c2410_wdt.c drivers/watchdog/sb_wdog.c drivers/watchdog/sbc7240_wdt.c drivers/watchdog/sbc_epx_c3.c drivers/watchdog/c1200wdt.c drivers/watchdog/sch311x_wdt.c drivers/watchdog/shwdt.c drivers/watchdog/smsc37b787_wdt.c drivers/watchdog/stmp3xxx_wdt.c drivers/watchdog/txx9wdt.c drivers/watchdog/w83697hf_wdt.c drivers/watchdog/w83877f_wdt.c drivers/watchdog/wafer5823wdt.c drivers/watchdog/wdrtas.c drivers/watchdog/wdt.c drivers/watchdog/wdt977.c drivers/watchdog/wdt_pci.c drivers/watchdog/wm8350_wdt.c -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/