From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753187AbaIYOr6 (ORCPT ); Thu, 25 Sep 2014 10:47:58 -0400 Received: from 8bytes.org ([81.169.241.247]:58197 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752600AbaIYOr5 (ORCPT ); Thu, 25 Sep 2014 10:47:57 -0400 Date: Thu, 25 Sep 2014 16:47:54 +0200 From: Joerg Roedel To: Mark Salter Cc: iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, Suravee Suthikulpanit Subject: Re: [PATCH] iommu/core: fix bus notifier breakage Message-ID: <20140925144754.GD8306@8bytes.org> References: <1411322304-3925-1-git-send-email-msalter@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1411322304-3925-1-git-send-email-msalter@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Sep 21, 2014 at 01:58:24PM -0400, Mark Salter wrote: > iommu_bus_init() registers a bus notifier on the given bus by using > a statically defined notifier block: > > static struct notifier_block iommu_bus_nb = { > .notifier_call = iommu_bus_notifier, > }; > > This same notifier block is used for all busses. This causes a > problem for notifiers registered after iommu has registered this > callback on multiple busses. The problem is that a subsequent > notifier being registered on a bus which has this iommu notifier > will also get linked in to the notifier list of all other busses > which have this iommu notifier. > > This patch fixes this by allocating the notifier_block at runtime. > Some error checking is also added to catch any allocation failure > or notifier registration error. > > Signed-off-by: Mark Salter > --- > drivers/iommu/iommu.c | 26 ++++++++++++++++---------- > 1 file changed, 16 insertions(+), 10 deletions(-) Makes sense, applied. Where have you hit this condition where IOMMUs for different buses are registered? Joerg