From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joerg Roedel Subject: Re: [GIT PULL] iommu/arm-smmu: Fixes for 4.9 Date: Thu, 3 Nov 2016 17:29:43 +0100 Message-ID: <20161103162943.GS3541@8bytes.org> References: <20161028160148.GD1076@arm.com> <20161103153303.GA837@8bytes.org> <20161103160006.GS22791@arm.com> <20161103161407.GR3541@8bytes.org> <0dbf2665-4292-d49a-b9e7-688bcdf29c6e@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <0dbf2665-4292-d49a-b9e7-688bcdf29c6e-5wv7dgnIgG8@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Robin Murphy Cc: iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, Will Deacon , linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: iommu@lists.linux-foundation.org On Thu, Nov 03, 2016 at 04:22:04PM +0000, Robin Murphy wrote: > But bus_set_iommu() is already checking whether another SMMU (in this > case) has probed, by virtue of bus->iommu_ops being non-NULL, and > returning without doing anything if so. What's the value of adding a > whole bunch more code to effectively duplicate that in a less elegant > manner? No, bus_set_iommu() checks whether there is _any_ other IOMMU already registered. This doesn't need to be an smmu. So I think the return value of bus_set_iommu shouldn't be generally ignored. Joerg