Why fcs_client app resulted in page allocation failure and unable to proceed when executing on Agilex™ 5 SoC FPGA Devices?

Description

Due to a problem with limited HPS memory resources on the Agilex™ 5 FPGA device (e.g., when deploying it with 1GB RAM or less), kernel memory allocation failures may occur, particularly when invoking crypto services operations via the HPS on a system with fragmented memory. Memory fragmentation can result from repeated crypto services operations, prolonged system uptime, or other workloads that dynamically allocate and free memory.

Resolution

To work around this problem, consider that the crypto services driver requires 4MB of contiguous memory for each encryption/decryption transaction in the kernel. While tuning parameters such as min_free_kbytes may help by encouraging earlier flushing of buffers or caches, they do not guarantee the reservation of contiguous memory. The Contiguous Memory Allocator (CMA) is enabled in the system, and its reserved size can be increased through kernel boot arguments to improve robustness against fragmentation-related failures. Users and system integrators are responsible for ensuring that the operating system is configured to meet the memory requirements of their expected workloads. Failure to do so may result in degraded performance, application instability, or functional failures.