Hmm, I'm a little confused on what this is trying to archive. The io_uring passthrough already does support multipathing, it picks an available path in nvme_ns_head_chr_uring_cmd and uses that. What this does is adding support for requeing on failure or the lack of an available path. Which very strongly is against our passthrough philosophy both in SCSI and NVMe where error handling is left entirely to the userspace program issuing the I/O. So this does radically change behavior in a very unexpected way. Why?