Re: [PATCH v8 00/18] KVM PCIe/MSI passthrough on ARM/ARM64 and IOVA reserved regions

[Auger Eric <eric.auger@redhat.com>]

Hi Bharat,
On 12/01/2017 04:59, Bharat Bhushan wrote:
> 
> 
>> -----Original Message-----
>> From: Eric Auger [mailto:eric.auger@redhat.com]
>> Sent: Wednesday, January 11, 2017 3:12 PM
>> To: eric.auger@redhat.com; eric.auger.pro@gmail.com;
>> christoffer.dall@linaro.org; marc.zyngier@arm.com;
>> robin.murphy@arm.com; alex.williamson@redhat.com;
>> will.deacon@arm.com; joro@8bytes.org; tglx@linutronix.de;
>> jason@lakedaemon.net; linux-arm-kernel@lists.infradead.org
>> Cc: kvm@vger.kernel.org; drjones@redhat.com; linux-
>> kernel@vger.kernel.org; pranav.sawargaonkar@gmail.com;
>> iommu@lists.linux-foundation.org; punit.agrawal@arm.com; Diana Madalina
>> Craciun <diana.craciun@nxp.com>; gpkulkarni@gmail.com;
>> shankerd@codeaurora.org; Bharat Bhushan <bharat.bhushan@nxp.com>;
>> geethasowjanya.akula@gmail.com
>> Subject: [PATCH v8 00/18] KVM PCIe/MSI passthrough on ARM/ARM64 and
>> IOVA reserved regions
>>
>> Following LPC discussions, we now report reserved regions through the
>> iommu-group sysfs reserved_regions attribute file.
>>
>> Reserved regions are populated through the IOMMU get_resv_region
>> callback (former get_dm_regions), now implemented by amd-iommu, intel-
>> iommu and arm-smmu:
>> - the intel-iommu reports the [0xfee00000 - 0xfeefffff] MSI window
>>   as a reserved region and RMRR regions as direct-mapped regions.
>> - the amd-iommu reports device direct mapped regions, the MSI region
>>   and HT regions.
>> - the arm-smmu reports the MSI window (arbitrarily located at
>>   0x8000000 and 1MB large).
>>
>> Unsafe interrupt assignment is tested by enumerating all MSI irq domains
>> and checking MSI remapping is supported in the above hierarchy.
>> This check is done in case we detect the iommu translates MSI (an
>> IOMMU_RESV_MSI window exists). Otherwise the IRQ remapping capability
>> is checked at IOMMU level. Obviously this is a defensive IRQ safety
>> assessment: Assuming there are several MSI controllers in the system and at
>> least one does not implement IRQ remapping, the assignment will be
>> considered as unsafe (even if this controller is not acessible from the
>> assigned devices).
>>
>> The series first patch stems from Robin's branch:
>> http://linux-arm.org/git?p=linux-
>> rm.git;a=shortlog;h=refs/heads/iommu/misc
>>
>> Best Regards
>>
>> Eric
>>
>> Git: complete series available at
>> https://github.com/eauger/linux/tree/v4.10-rc3-reserved-v8
> 
> This series is tested on NXP platform, if you want you can add my tested by
> Tested-by: Bharat Bhushan <bharat.bhushan@nxp.com>
Thank you for this!

Best Regards

Eric
> 
> Thanks
> -Bharat
> 
>>
>> istory:
>>
>> PATCHv7 -> PATCHv8
>> - take into account Marc's comments and apply his R-b
>> - remove iommu_group_remove_file call in iommu_group_release
>> - add Will's A-b
>> - removed [PATCH v7 01/19] iommu/dma: Implement PCI allocation
>>   optimisation and updated iommu/dma: Allow MSI-only cookies
>>   as per Robin's indications
>>
>> PATCHv6 -> PATCHv7:
>> - iommu/dma: Implement PCI allocation optimisation was added to apply
>>   iommu/dma: Allow MSI-only cookies
>> - report Intel RMRR as direct-mapped regions
>> - report the type in the iommu group sysfs reserved_regions file
>> - do not merge regions of different types when building the list
>>   of reserved regions
>> - intgeration Robin's "iommu/dma: Allow MSI-only cookies" last
>>   version
>> - update Documentation/ABI/testing/sysfs-kernel-iommu_groups
>> - rename IOMMU_RESV_NOMAP into IOMMU_RESV_RESERVED
>>
>> PATCHv5 -> PATCHv6
>> - Introduce IRQ_DOMAIN_FLAG_MSI as suggested by Marc
>> - irq_domain_is_msi, irq_domain_is_msi_remap,
>>   irq_domain_hierarchical_is_msi_remap,
>> - set IRQ_DOMAIN_FLAG_MSI in msi_create_irq_domain
>> - fix compil issue on i386
>> - rework test at VFIO level
>>
>> RFCv4 -> PATCHv5
>> - fix IRQ security assessment by looking at irq domain parents
>> - check DOMAIN_BUS_FSL_MC_MSI irq domains
>> - AMD MSI and HT regions are exposed in iommu group sysfs
>>
>> RFCv3 -> RFCv4:
>> - arm-smmu driver does not register PCI host bridge windows as
>>   reserved regions anymore
>> - Implement reserved region get/put callbacks also in arm-smmuv3
>> - take the iommu_group lock on iommu_get_group_resv_regions
>> - add a type field in iommu_resv_region instead of using prot
>> - init the region list_head in iommu_alloc_resv_region, also
>>   add type parameter
>> - iommu_insert_resv_region manage overlaps and sort reserved
>>   windows
>> - address IRQ safety assessment by enumerating all the MSI irq
>>   domains and checking the MSI_REMAP flag
>> - update Documentation/ABI/testing/sysfs-kernel-iommu_groups
>>
>> RFC v2 -> v3:
>> - switch to an iommu-group sysfs API
>> - use new dummy allocator provided by Robin
>> - dummy allocator initialized by vfio-iommu-type1 after enumerating
>>   the reserved regions
>> - at the moment ARM MSI base address/size is left unchanged compared
>>   to v2
>> - we currently report reserved regions and not usable IOVA regions as
>>   requested by Alex
>>
>> RFC v1 -> v2:
>> - fix intel_add_reserved_regions
>> - add mutex lock/unlock in vfio_iommu_type1
>>
>>
>> Eric Auger (17):
>>   iommu: Rename iommu_dm_regions into iommu_resv_regions
>>   iommu: Add a new type field in iommu_resv_region
>>   iommu: iommu_alloc_resv_region
>>   iommu: Only map direct mapped regions
>>   iommu: iommu_get_group_resv_regions
>>   iommu: Implement reserved_regions iommu-group sysfs file
>>   iommu/vt-d: Implement reserved region get/put callbacks
>>   iommu/amd: Declare MSI and HT regions as reserved IOVA regions
>>   iommu/arm-smmu: Implement reserved region get/put callbacks
>>   iommu/arm-smmu-v3: Implement reserved region get/put callbacks
>>   irqdomain: Add irq domain MSI and MSI_REMAP flags
>>   genirq/msi: Set IRQ_DOMAIN_FLAG_MSI on MSI domain creation
>>   irqdomain: irq_domain_check_msi_remap
>>   irqchip/gicv3-its: Sets IRQ_DOMAIN_FLAG_MSI_REMAP
>>   vfio/type1: Allow transparent MSI IOVA allocation
>>   vfio/type1: Check MSI remapping at irq domain level
>>   iommu/arm-smmu: Do not advertise IOMMU_CAP_INTR_REMAP anymore
>>
>> Robin Murphy (1):
>>   iommu/dma: Allow MSI-only cookies
>>
>>  .../ABI/testing/sysfs-kernel-iommu_groups          |  12 ++
>>  drivers/iommu/amd_iommu.c                          |  54 ++++---
>>  drivers/iommu/arm-smmu-v3.c                        |  30 +++-
>>  drivers/iommu/arm-smmu.c                           |  30 +++-
>>  drivers/iommu/dma-iommu.c                          | 119 +++++++++++---
>>  drivers/iommu/intel-iommu.c                        |  92 ++++++++---
>>  drivers/iommu/iommu.c                              | 177 +++++++++++++++++++--
>>  drivers/irqchip/irq-gic-v3-its.c                   |   1 +
>>  drivers/vfio/vfio_iommu_type1.c                    |  37 ++++-
>>  include/linux/dma-iommu.h                          |   6 +
>>  include/linux/iommu.h                              |  46 ++++--
>>  include/linux/irqdomain.h                          |  36 +++++
>>  kernel/irq/irqdomain.c                             |  36 +++++
>>  kernel/irq/msi.c                                   |   4 +-
>>  14 files changed, 587 insertions(+), 93 deletions(-)
>>
>> --
>> 1.9.1
>