Hello Eric,

On 11.01.2017 10:41, Eric Auger wrote:
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:

Best Regards


Git: complete series available at

I tested the series on ThunderX with internal 10G VNIC and Intel IXGBE NIC. Please feel free to add my:
Tested-by: Tomasz Nowicki <tomasz.nowi...@caviumnetworks.com>


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