esize parameter. libata shouldn't call blk_queue_max_phys_segments. Now LIBATA_MAX_PRD is equal to SCSI_MAX_PHYS_SEGMENTS by default (both is 128), so everything is fine. But if they are changed, some code (like the scsi mid layer, sg chaining, etc) might not work properly. (Addition from Jens) The basic issue is that the physical segment setting is purely a driver issue. And since SCSI is managing the sglist, libata has no business changing the setting. All libata should care about is the hw segment setting. Signed-off-by: FUJITA Tomonori Signed-off-by: Jens Axboe ˜¤iê“