From mboxrd@z Thu Jan 1 00:00:00 1970 From: laurent.pinchart@ideasonboard.com (Laurent Pinchart) Date: Tue, 13 Jan 2015 16:53:44 +0200 Subject: [PATCH 2/2] ARM: dma-mapping: don't detach devices without an IOMMU during teardown In-Reply-To: <1421083413-24798-3-git-send-email-will.deacon@arm.com> References: <1421083413-24798-1-git-send-email-will.deacon@arm.com> <1421083413-24798-3-git-send-email-will.deacon@arm.com> Message-ID: <2890986.UZklX6cuTS@avalon> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Will, Thank you for the patch. On Monday 12 January 2015 17:23:33 Will Deacon wrote: > When tearing down the DMA ops for a device via of_dma_deconfigure, we > unconditionally detach the device from its IOMMU domain. For devices > that aren't actually behind an IOMMU, this produces a "Not attached" > warning message on the console. > > This patch changes the teardown code so that we don't detach from the > IOMMU domain when there isn't an IOMMU dma mapping to start with. > > Repoerted-by: Laurent Pinchart I might have reported the problem, but I haven't repoerted it :-) > Signed-off-by: Will Deacon > --- > arch/arm/mm/dma-mapping.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c > index 7864797609b3..711c3d2802fb 100644 > --- a/arch/arm/mm/dma-mapping.c > +++ b/arch/arm/mm/dma-mapping.c > @@ -2023,7 +2023,10 @@ static bool arm_setup_iommu_dma_ops(struct device > *dev, u64 dma_base, u64 size, > > static void arm_teardown_iommu_dma_ops(struct device *dev) > { > - struct dma_iommu_mapping *mapping = dev->archdata.mapping; > + struct dma_iommu_mapping *mapping = to_dma_iommu_mapping(dev); As the function is already protected by an #ifdef CONFIG_ARM_DMA_USE_IOMMU is there a specific reason for this change ? > + > + if (!mapping) > + return; > > arm_iommu_detach_device(dev); > arm_iommu_release_mapping(mapping); -- Regards, Laurent Pinchart