search for: pasid

...versions will extend it. > > >> * Simplify PROBE request by removing the ack part, and flattening RESV > > >> properties. > > >> * Rename "address space" to "domain". The change might seem futile but > > >> allows to introduce PASIDs and other features cleanly in the next > > >> versions. In the same vein, the few remaining "device" occurrences were > > >> replaced by "endpoint", to avoid any confusion with "the device" > > >> referring to the virtio devic...

...t; >> future versions will extend it. > >> * Simplify PROBE request by removing the ack part, and flattening RESV > >> properties. > >> * Rename "address space" to "domain". The change might seem futile but > >> allows to introduce PASIDs and other features cleanly in the next > >> versions. In the same vein, the few remaining "device" occurrences were > >> replaced by "endpoint", to avoid any confusion with "the device" > >> referring to the virtio device across the do...

...t; >> future versions will extend it. > >> * Simplify PROBE request by removing the ack part, and flattening RESV > >> properties. > >> * Rename "address space" to "domain". The change might seem futile but > >> allows to introduce PASIDs and other features cleanly in the next > >> versions. In the same vein, the few remaining "device" occurrences were > >> replaced by "endpoint", to avoid any confusion with "the device" > >> referring to the virtio device across the do...

...lt pending. Given that the PCI spec does not indicate a timeout, the guest can wait as long as it wants to complete the fault (and 100ms may even be reasonable on an emulator, who knows how many layers and context switches the fault has to go through). Another outstanding issue was what to do for PASID stop. When the guest device driver stops using a PASID it issues a PASID stop request to the device (a device-specific mechanism). If the device is not using PRI stop markers it waits for pending PRs to complete and we're fine. Otherwise it sends a stop marker which is flushed to the PRI queue,...

...s will extend it. >>>>> * Simplify PROBE request by removing the ack part, and flattening RESV >>>>> properties. >>>>> * Rename "address space" to "domain". The change might seem futile but >>>>> allows to introduce PASIDs and other features cleanly in the next >>>>> versions. In the same vein, the few remaining "device" occurrences were >>>>> replaced by "endpoint", to avoid any confusion with "the device" >>>>> referring to the virtio...

...t; >>>>> * Simplify PROBE request by removing the ack part, and flattening RESV > >>>>> properties. > >>>>> * Rename "address space" to "domain". The change might seem futile but > >>>>> allows to introduce PASIDs and other features cleanly in the next > >>>>> versions. In the same vein, the few remaining "device" occurrences were > >>>>> replaced by "endpoint", to avoid any confusion with "the device" > >>>>> referrin...

...t; >>>>> * Simplify PROBE request by removing the ack part, and flattening RESV > >>>>> properties. > >>>>> * Rename "address space" to "domain". The change might seem futile but > >>>>> allows to introduce PASIDs and other features cleanly in the next > >>>>> versions. In the same vein, the few remaining "device" occurrences were > >>>>> replaced by "endpoint", to avoid any confusion with "the device" > >>>>> referrin...

...ults are available but >> future versions will extend it. >> * Simplify PROBE request by removing the ack part, and flattening RESV >> properties. >> * Rename "address space" to "domain". The change might seem futile but >> allows to introduce PASIDs and other features cleanly in the next >> versions. In the same vein, the few remaining "device" occurrences were >> replaced by "endpoint", to avoid any confusion with "the device" >> referring to the virtio device across the document. >&gt...

...e at the device which is also allowed by the IOMMU to poke at kernel memory (needed for kernel driver to work). Yes, maybe if device is not buggy it's all fine, but it's better if we do not have to trust the device otherwise the security picture becomes more murky. I suggested attaching a PASID to (some) queues - see my old post "using PASIDs to enable a safe variant of direct ring access". Then using IOMMU with VFIO to limit access through queue to corrent ranges of memory. -- MST

...e at the device which is also allowed by the IOMMU to poke at kernel memory (needed for kernel driver to work). Yes, maybe if device is not buggy it's all fine, but it's better if we do not have to trust the device otherwise the security picture becomes more murky. I suggested attaching a PASID to (some) queues - see my old post "using PASIDs to enable a safe variant of direct ring access". Then using IOMMU with VFIO to limit access through queue to corrent ranges of memory. -- MST

...nly unrecoverable faults are available but > future versions will extend it. > * Simplify PROBE request by removing the ack part, and flattening RESV > properties. > * Rename "address space" to "domain". The change might seem futile but > allows to introduce PASIDs and other features cleanly in the next > versions. In the same vein, the few remaining "device" occurrences were > replaced by "endpoint", to avoid any confusion with "the device" > referring to the virtio device across the document. > * Add implemen...

...driver. For the moment only unrecoverable faults are available but future versions will extend it. * Simplify PROBE request by removing the ack part, and flattening RESV properties. * Rename "address space" to "domain". The change might seem futile but allows to introduce PASIDs and other features cleanly in the next versions. In the same vein, the few remaining "device" occurrences were replaced by "endpoint", to avoid any confusion with "the device" referring to the virtio device across the document. * Add implementation notes for RES...

...driver. For the moment only unrecoverable faults are available but future versions will extend it. * Simplify PROBE request by removing the ack part, and flattening RESV properties. * Rename "address space" to "domain". The change might seem futile but allows to introduce PASIDs and other features cleanly in the next versions. In the same vein, the few remaining "device" occurrences were replaced by "endpoint", to avoid any confusion with "the device" referring to the virtio device across the document. * Add implementation notes for RES...

...IOMMU > drivers don't support mdev bus. > > > > > Yes, maybe if device is not buggy it's all fine, but it's better if we > > do not have to trust the device otherwise the security picture becomes > > more murky. > > > > I suggested attaching a PASID to (some) queues - see my old post > > "using PASIDs to enable a safe variant of direct ring access". > Ideally we can have a device binding with normal driver in host, meanwhile support to allocate a few queues attaching with PASID on-demand. By vhost mdev transport channel, th...

...ected translation failure (dev=00:03:00, iova=0x1d40000030c0) qemu-system-x86_64: New fault is not recorded due to compression of faults Guest kernel messages: [ 44.940872] DMAR: DRHD: handling fault status reg 2 [ 44.941989] DMAR: [DMA Read] Request device [00:03.0] PASID ffffffff fault addr ffff88W [ 49.785884] DMAR: DRHD: handling fault status reg 2 [ 49.788874] DMAR: [DMA Read] Request device [00:03.0] PASID ffffffff fault addr ffff88W QEMU: b149dea55c Merge remote-tracking branch 'remotes/cschoenebeck/tags/pull-9p-20201102' i...

...> > Introducing a probe request is more flexible than advertising those > features in virtio config, because capabilities are dynamic, and depend on > which devices are attached to an address space. Within a single address > space, devices may support different numbers of contexts (PASIDs), and > some may not support recoverable faults. > > (3) Device responds success with all page table formats implemented by the > physical IOMMU in pg_format. 'model' 0 is invalid, so driver can > initialize the array to 0 and deduce from there which entries have &g...

...> > Introducing a probe request is more flexible than advertising those > features in virtio config, because capabilities are dynamic, and depend on > which devices are attached to an address space. Within a single address > space, devices may support different numbers of contexts (PASIDs), and > some may not support recoverable faults. > > (3) Device responds success with all page table formats implemented by the > physical IOMMU in pg_format. 'model' 0 is invalid, so driver can > initialize the array to 0 and deduce from there which entries have &g...

...t on top of VFIO for sure. So kernel memory were perfectly isolated in this case. > > Yes, maybe if device is not buggy it's all fine, but > it's better if we do not have to trust the device > otherwise the security picture becomes more murky. > > I suggested attaching a PASID to (some) queues - see my old post "using > PASIDs to enable a safe variant of direct ring access". > > Then using IOMMU with VFIO to limit access through queue to corrent > ranges of memory. Well userspace driver could benefit from this too. And we can even go further by us...

...userspace directly is that, currently IOMMU drivers don't support mdev bus. > > Yes, maybe if device is not buggy it's all fine, but > it's better if we do not have to trust the device > otherwise the security picture becomes more murky. > > I suggested attaching a PASID to (some) queues - see my old post "using > PASIDs to enable a safe variant of direct ring access". It's pretty cool. We also have some similar ideas. Cunming will talk more about this. Best regards, Tiwei Bie > > Then using IOMMU with VFIO to limit access through queue t...

...host1x/cdma.c | 2 +- drivers/infiniband/hw/usnic/usnic_uiom.c | 4 +- drivers/iommu/dma-iommu.c | 11 ++--- drivers/iommu/intel/iommu.c | 36 +++++++++------- drivers/iommu/intel/iommu.h | 2 +- drivers/iommu/intel/pasid.c | 2 +- drivers/iommu/iommu.c | 43 +++++-------------- drivers/iommu/iommufd/pages.c | 6 ++- drivers/iommu/s390-iommu.c | 15 ++++--- drivers/media/platform/qcom/venus/firmware.c | 2 +- drivers/net/ipa/ipa_mem.c...