From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932534Ab1I1Wnd (ORCPT ); Wed, 28 Sep 2011 18:43:33 -0400 Received: from cantor2.suse.de ([195.135.220.15]:54198 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932500Ab1I1WnY (ORCPT ); Wed, 28 Sep 2011 18:43:24 -0400 X-Mailbox-Line: From gregkh@clark.kroah.org Wed Sep 28 15:01:37 2011 Message-Id: <20110928220137.657830411@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Wed, 28 Sep 2011 15:01:21 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Geert Uytterhoeven , linux-m68k@vger.kernel.org, Thomas Gleixner Subject: [117/244] genirq: Make irq_shutdown() symmetric vs. irq_startup again In-Reply-To: <20110928220225.GA27128@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.0-stable review patch. If anyone has any objections, please let us know. ------------------ From: Geert Uytterhoeven commit ed585a651681e822089087b426e6ebfb6d3d9873 upstream. If an irq_chip provides .irq_shutdown(), but neither of .irq_disable() or .irq_mask(), free_irq() crashes when jumping to NULL. Fix this by only trying .irq_disable() and .irq_mask() if there's no .irq_shutdown() provided. This revives the symmetry with irq_startup(), which tries .irq_startup(), .irq_enable(), and irq_unmask(), and makes it consistent with the comment for irq_chip.irq_shutdown() in , which says: * @irq_shutdown: shut down the interrupt (defaults to ->disable if NULL) This is also how __free_irq() behaved before the big overhaul, cfr. e.g. 3b56f0585fd4c02d047dc406668cb40159b2d340 ("genirq: Remove bogus conditional"), where the core interrupt code always overrode .irq_shutdown() to .irq_disable() if .irq_shutdown() was NULL. Signed-off-by: Geert Uytterhoeven Cc: linux-m68k@lists.linux-m68k.org Link: http://lkml.kernel.org/r/1315742394-16036-2-git-send-email-geert@linux-m68k.org Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman --- kernel/irq/chip.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -178,7 +178,7 @@ void irq_shutdown(struct irq_desc *desc) desc->depth = 1; if (desc->irq_data.chip->irq_shutdown) desc->irq_data.chip->irq_shutdown(&desc->irq_data); - if (desc->irq_data.chip->irq_disable) + else if (desc->irq_data.chip->irq_disable) desc->irq_data.chip->irq_disable(&desc->irq_data); else desc->irq_data.chip->irq_mask(&desc->irq_data);