We found some strange devices in HP C7000 and Huawei Server. These devices
can not be enumerated by OS, but they still did DMA read/write without OS
management. Because iommu will not create the DMA mapping for these devices,
the DMA read/write will be blocked by iommu hardware.
Eg.
On Mon, 2014-08-11 at 10:54 +0800, Yijing Wang wrote:
We found some strange devices in HP C7000 and Huawei Server. These devices
can not be enumerated by OS, but they still did DMA read/write without OS
management. Because iommu will not create the DMA mapping for these devices,
the DMA
Hi Yijing,
These devices don't support Phantom Function (PhantFunc 0).
Could you please help to provide full dmesg, /proc/iomem, and ACPI
DMAR table? You may get DMAR table by:
acpidump acpi.bin
acpixtract -a acpib.bin
iasl -d DMAR.dat
Thanks!
Gerry
On 2014/8/11 11:46, Yijing Wang wrote: