Message ID | 1495795417-15177-1-git-send-email-sricharan@codeaurora.org (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Hi Sricharan, Thank you for the patch. On Friday 26 May 2017 16:13:37 Sricharan R wrote: > arch_teardown_dma_ops() being the inverse of arch_setup_dma_ops() > ,dma_ops should be cleared in the teardown path. Currently, only the > device's iommu mapping structures are cleared in arch_teardown_dma_ops, > but not the dma_ops. So on the next reprobe, dma_ops left in place is > stale from the first IOMMU setup, but iommu mappings has been disposed > of. This is a problem when the probe of the device is deferred and > recalled with the IOMMU probe deferral. > > So for fixing this, slightly refactor by moving the code from > __arm_iommu_detach_device to arm_iommu_detach_device and cleanup > the former. This takes care of resetting the dma_ops in the teardown > path. > > Signed-off-by: Sricharan R <sricharan@codeaurora.org> > Fixes: 09515ef5ddad ("of/acpi: Configure dma operations at probe time for > platform/amba/pci bus devices") Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Could you please push this upstream along with "[PATCH] ARM: dma-mapping: Don't tear third-party mappings" ? (And feel free to s/tear/tear down/ in the subject of that patch, I've only noticed now that I forgot one word) > --- > arch/arm/mm/dma-mapping.c | 25 ++++++++++--------------- > 1 file changed, 10 insertions(+), 15 deletions(-) > > diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c > index c742dfd..6e82e87 100644 > --- a/arch/arm/mm/dma-mapping.c > +++ b/arch/arm/mm/dma-mapping.c > @@ -2311,7 +2311,14 @@ int arm_iommu_attach_device(struct device *dev, > } > EXPORT_SYMBOL_GPL(arm_iommu_attach_device); > > -static void __arm_iommu_detach_device(struct device *dev) > +/** > + * arm_iommu_detach_device > + * @dev: valid struct device pointer > + * > + * Detaches the provided device from a previously attached map. > + * This voids the dma operations (dma_map_ops pointer) > + */ > +void arm_iommu_detach_device(struct device *dev) > { > struct dma_iommu_mapping *mapping; > > @@ -2324,22 +2331,10 @@ static void __arm_iommu_detach_device(struct device > *dev) iommu_detach_device(mapping->domain, dev); > kref_put(&mapping->kref, release_iommu_mapping); > to_dma_iommu_mapping(dev) = NULL; > + set_dma_ops(dev, NULL); > > pr_debug("Detached IOMMU controller from %s device.\n", dev_name(dev)); > } > - > -/** > - * arm_iommu_detach_device > - * @dev: valid struct device pointer > - * > - * Detaches the provided device from a previously attached map. > - * This voids the dma operations (dma_map_ops pointer) > - */ > -void arm_iommu_detach_device(struct device *dev) > -{ > - __arm_iommu_detach_device(dev); > - set_dma_ops(dev, NULL); > -} > EXPORT_SYMBOL_GPL(arm_iommu_detach_device); > > static const struct dma_map_ops *arm_get_iommu_dma_map_ops(bool coherent) > @@ -2379,7 +2374,7 @@ static void arm_teardown_iommu_dma_ops(struct device > *dev) if (!mapping) > return; > > - __arm_iommu_detach_device(dev); > + arm_iommu_detach_device(dev); > arm_iommu_release_mapping(mapping); > }
Hi Laurent, On 5/26/2017 7:44 PM, Laurent Pinchart wrote: > Hi Sricharan, > > Thank you for the patch. > > On Friday 26 May 2017 16:13:37 Sricharan R wrote: >> arch_teardown_dma_ops() being the inverse of arch_setup_dma_ops() >> ,dma_ops should be cleared in the teardown path. Currently, only the >> device's iommu mapping structures are cleared in arch_teardown_dma_ops, >> but not the dma_ops. So on the next reprobe, dma_ops left in place is >> stale from the first IOMMU setup, but iommu mappings has been disposed >> of. This is a problem when the probe of the device is deferred and >> recalled with the IOMMU probe deferral. >> >> So for fixing this, slightly refactor by moving the code from >> __arm_iommu_detach_device to arm_iommu_detach_device and cleanup >> the former. This takes care of resetting the dma_ops in the teardown >> path. >> >> Signed-off-by: Sricharan R <sricharan@codeaurora.org> >> Fixes: 09515ef5ddad ("of/acpi: Configure dma operations at probe time for >> platform/amba/pci bus devices") > > Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > > Could you please push this upstream along with "[PATCH] ARM: dma-mapping: > Don't tear third-party mappings" ? > > (And feel free to s/tear/tear down/ in the subject of that patch, I've only > noticed now that I forgot one word) ok, will change the above and post it with the other patches. Regards, Sricharan > >> --- >> arch/arm/mm/dma-mapping.c | 25 ++++++++++--------------- >> 1 file changed, 10 insertions(+), 15 deletions(-) >> >> diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c >> index c742dfd..6e82e87 100644 >> --- a/arch/arm/mm/dma-mapping.c >> +++ b/arch/arm/mm/dma-mapping.c >> @@ -2311,7 +2311,14 @@ int arm_iommu_attach_device(struct device *dev, >> } >> EXPORT_SYMBOL_GPL(arm_iommu_attach_device); >> >> -static void __arm_iommu_detach_device(struct device *dev) >> +/** >> + * arm_iommu_detach_device >> + * @dev: valid struct device pointer >> + * >> + * Detaches the provided device from a previously attached map. >> + * This voids the dma operations (dma_map_ops pointer) >> + */ >> +void arm_iommu_detach_device(struct device *dev) >> { >> struct dma_iommu_mapping *mapping; >> >> @@ -2324,22 +2331,10 @@ static void __arm_iommu_detach_device(struct device >> *dev) iommu_detach_device(mapping->domain, dev); >> kref_put(&mapping->kref, release_iommu_mapping); >> to_dma_iommu_mapping(dev) = NULL; >> + set_dma_ops(dev, NULL); >> >> pr_debug("Detached IOMMU controller from %s device.\n", > dev_name(dev)); >> } >> - >> -/** >> - * arm_iommu_detach_device >> - * @dev: valid struct device pointer >> - * >> - * Detaches the provided device from a previously attached map. >> - * This voids the dma operations (dma_map_ops pointer) >> - */ >> -void arm_iommu_detach_device(struct device *dev) >> -{ >> - __arm_iommu_detach_device(dev); >> - set_dma_ops(dev, NULL); >> -} >> EXPORT_SYMBOL_GPL(arm_iommu_detach_device); >> >> static const struct dma_map_ops *arm_get_iommu_dma_map_ops(bool coherent) >> @@ -2379,7 +2374,7 @@ static void arm_teardown_iommu_dma_ops(struct device >> *dev) if (!mapping) >> return; >> >> - __arm_iommu_detach_device(dev); >> + arm_iommu_detach_device(dev); >> arm_iommu_release_mapping(mapping); >> } >
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index c742dfd..6e82e87 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -2311,7 +2311,14 @@ int arm_iommu_attach_device(struct device *dev, } EXPORT_SYMBOL_GPL(arm_iommu_attach_device); -static void __arm_iommu_detach_device(struct device *dev) +/** + * arm_iommu_detach_device + * @dev: valid struct device pointer + * + * Detaches the provided device from a previously attached map. + * This voids the dma operations (dma_map_ops pointer) + */ +void arm_iommu_detach_device(struct device *dev) { struct dma_iommu_mapping *mapping; @@ -2324,22 +2331,10 @@ static void __arm_iommu_detach_device(struct device *dev) iommu_detach_device(mapping->domain, dev); kref_put(&mapping->kref, release_iommu_mapping); to_dma_iommu_mapping(dev) = NULL; + set_dma_ops(dev, NULL); pr_debug("Detached IOMMU controller from %s device.\n", dev_name(dev)); } - -/** - * arm_iommu_detach_device - * @dev: valid struct device pointer - * - * Detaches the provided device from a previously attached map. - * This voids the dma operations (dma_map_ops pointer) - */ -void arm_iommu_detach_device(struct device *dev) -{ - __arm_iommu_detach_device(dev); - set_dma_ops(dev, NULL); -} EXPORT_SYMBOL_GPL(arm_iommu_detach_device); static const struct dma_map_ops *arm_get_iommu_dma_map_ops(bool coherent) @@ -2379,7 +2374,7 @@ static void arm_teardown_iommu_dma_ops(struct device *dev) if (!mapping) return; - __arm_iommu_detach_device(dev); + arm_iommu_detach_device(dev); arm_iommu_release_mapping(mapping); }
arch_teardown_dma_ops() being the inverse of arch_setup_dma_ops() ,dma_ops should be cleared in the teardown path. Currently, only the device's iommu mapping structures are cleared in arch_teardown_dma_ops, but not the dma_ops. So on the next reprobe, dma_ops left in place is stale from the first IOMMU setup, but iommu mappings has been disposed of. This is a problem when the probe of the device is deferred and recalled with the IOMMU probe deferral. So for fixing this, slightly refactor by moving the code from __arm_iommu_detach_device to arm_iommu_detach_device and cleanup the former. This takes care of resetting the dma_ops in the teardown path. Signed-off-by: Sricharan R <sricharan@codeaurora.org> Fixes: 09515ef5ddad ("of/acpi: Configure dma operations at probe time for platform/amba/pci bus devices") --- arch/arm/mm/dma-mapping.c | 25 ++++++++++--------------- 1 file changed, 10 insertions(+), 15 deletions(-)