Device Family: Intel® Arria® 10 GX

Intel Software: Quartus Prime Pro

Type: Answers, Errata

Area: Embedded


Last Modified: April 09, 2018
Version Found: v17.0
Bug ID: FB: 537520;

Why does my OPAE driver stop working after an invalid IOMMU read?

Description

Due to a problem in the 1.0 release of the Intel® Acceleration Stack for Intel Xeon® CPU with FPGAs, if the AFU reads host memory at an invalid address, then the FPGA stops responding. 

Workaround/Fix

Verify your AFU is reading a valid host region.  See Shared Memory APIs for a description of how to allocate and share system memory with an AFU.  See the hello_fpga code example which shows use of these APIs. 

If this condition occurs, then a power cycle of the system is required to recover. 

A future release of the Intel® Acceleration Stack for Intel Xeon® CPU with FPGAs will allow the FPGA to continue to respond when the AFU reads an invalid host memory location.