iSCSI hook and IOMMU

[parthy]

Well, the situation is that the kernel does not have a NIC driver, but configures the IOMMU. The INT13 hook is transparent and continues to function if the IOMMU is configured correctly. The way to report this would be the RMRR descriptors in the DMAR table. I suspect that is how hardware iSCSI mechanisms provided by the firmware do it. The VT-d specification says:

Quote:Section 3.15 described the details of BIOS allocated reserved memory ranges that may be DMA targets. BIOS may report each such reserved memory region through the RMRR structures, along with the devices that requires access to the specified reserved memory region.

This sounds like the appropriate mechanism, if iPXE is viewed as part of the "BIOS".