Suganath, > + /* > + ** Below code detects gaps/holes in IO data buffers. > + ** What does holes/gaps mean? > + ** Any SGE except first one in a SGL starts at non NVME page size > + ** aligned address OR Any SGE except last one in a SGL ends at > + ** non NVME page size boundary. > + ** > + ** Driver has already informed block layer by setting boundary rules > + ** for bio merging done at NVME page size boundary calling kernel API > + ** blk_queue_virt_boundary inside slave_config. > + ** Still there is possibility of IO coming with holes to driver because > + ** of IO merging done by IO scheduler. All this SGL to PRP code needs to go. If you are seeing anything that's not a valid PRP after setting the queue virt boundary then there's a block layer bug that needs to be debugged and fixed. Regardless of whether you are using an I/O scheduler or not. -- Martin K. Petersen Oracle Linux Engineering