From mboxrd@z Thu Jan 1 00:00:00 1970 From: will.deacon@arm.com (Will Deacon) Date: Tue, 13 Jan 2015 15:24:45 +0000 Subject: [PATCH 2/2] ARM: dma-mapping: don't detach devices without an IOMMU during teardown In-Reply-To: <2890986.UZklX6cuTS@avalon> References: <1421083413-24798-1-git-send-email-will.deacon@arm.com> <1421083413-24798-3-git-send-email-will.deacon@arm.com> <2890986.UZklX6cuTS@avalon> Message-ID: <20150113152445.GD31784@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tue, Jan 13, 2015 at 02:53:44PM +0000, Laurent Pinchart wrote: > 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 :-) D'oh, fat fingers. Sorry! > > 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 ? I just wanted to hide the archdata access, since we shouldn't really care where it's stored. I could do it as a seperate patch, but I was in the area... Will