Enable debugging of DMA-API usage

modulename: debug.ko


Linux Kernel Configuration
└─>Library routines
└─>Enable debugging of DMA-API usage
In linux kernel since version 2.6.30 (release Date: 2009-06-09)  
Enable this option to debug the use of the DMA API by device drivers.
With this option you will be able to detect common bugs in device
drivers like double-freeing of DMA mappings or freeing mappings that
were never allocated.

This option causes a performance degradation. Use only if you want to
debug device drivers and dma interactions.

If unsure, say N.

source code: