| Message ID | 2f5833b7639543d614095cd3f5ab0dc0274e26d6.1548081277.git.robin.murphy@arm.com (mailing list archive) |
|---|---|
| State | Mainlined, archived |
| Commit | fc67e6f120a388b611d94cc40baf99a5cc56b283 |
| Headers | show |
| Series | ARM: dma-mapping: Clear DMA ops on teardown | expand |
On Mon, Jan 21, 2019 at 02:52:16PM +0000, Robin Murphy wrote: > Installing the appropriate non-IOMMU DMA ops in arm_iommu_detch_device() > serves the case where IOMMU-aware drivers choose to control their own > mapping but still make DMA API calls, however it also affects the case > when the arch code itself tears down the mapping upon driver unbinding, > where the ops now get left in place and can inhibit arch_setup_dma_ops() > on subsequent re-probe attempts. > > Fix the latter case by making sure that arch_teardown_dma_ops() cleans > up whenever the ops were automatically installed by its counterpart. > > Reported-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de> > Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> > Fixes: 1874619a7df4 "ARM: dma-mapping: Set proper DMA ops in arm_iommu_detach_device()" > Tested-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de> > Signed-off-by: Robin Murphy <robin.murphy@arm.com> > --- > > Sorry for the delay - there was a giant email infrastructure cock-up just > at the point I wanted to go back through my archive and double-check the > discussion around the original commit... > > Robin. > > arch/arm/mm/dma-mapping.c | 2 ++ > 1 file changed, 2 insertions(+) I had also tested your draft on Tegra last week and this looks identical, so: Tested-by: Thierry Reding <treding@nvidia.com>
Hi Robin, On 2019-01-21 15:52, Robin Murphy wrote: > Installing the appropriate non-IOMMU DMA ops in arm_iommu_detch_device() > serves the case where IOMMU-aware drivers choose to control their own > mapping but still make DMA API calls, however it also affects the case > when the arch code itself tears down the mapping upon driver unbinding, > where the ops now get left in place and can inhibit arch_setup_dma_ops() > on subsequent re-probe attempts. > > Fix the latter case by making sure that arch_teardown_dma_ops() cleans > up whenever the ops were automatically installed by its counterpart. > > Reported-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de> > Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> > Fixes: 1874619a7df4 "ARM: dma-mapping: Set proper DMA ops in arm_iommu_detach_device()" > Tested-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de> > Signed-off-by: Robin Murphy <robin.murphy@arm.com> > --- > > Sorry for the delay - there was a giant email infrastructure cock-up just > at the point I wanted to go back through my archive and double-check the > discussion around the original commit... No problem, could you also upload it to rmk's patch tracking system? IMHO rmk's tree will be the best place to handle this fix. > Robin. > > arch/arm/mm/dma-mapping.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c > index f1e2922e447c..1e3e08a1c456 100644 > --- a/arch/arm/mm/dma-mapping.c > +++ b/arch/arm/mm/dma-mapping.c > @@ -2390,4 +2390,6 @@ void arch_teardown_dma_ops(struct device *dev) > return; > > arm_teardown_iommu_dma_ops(dev); > + /* Let arch_setup_dma_ops() start again from scratch upon re-probe */ > + set_dma_ops(dev, NULL); > } Best regards
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index f1e2922e447c..1e3e08a1c456 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -2390,4 +2390,6 @@ void arch_teardown_dma_ops(struct device *dev) return; arm_teardown_iommu_dma_ops(dev); + /* Let arch_setup_dma_ops() start again from scratch upon re-probe */ + set_dma_ops(dev, NULL); }