On Thu, Jan 25, 2024 at 11:28:22AM +0000, John Garry wrote: > We have limits checks in XFS iomap and fops.c, but we would also want to > ensure that the the block layer is not doing anything it shouldn't be doing > after submit_bio_noacct(), like merging atomic write BIOs which straddle a > boundary or exceed atomic_max (if there were any merging). > > The SCSI standard already has provision for error'ing an atomic write > command which exceeds the target atomic write capabilities, while NVMe > doesn't. Can you get Oracle to propose this for NVMe? It always helps if these suggestions come from a large buyer of NVMe equipment. > BTW, Christoph did mention that he would like to see this: > https://lore.kernel.org/linux-nvme/20231109153603.GA2188@xxxxxx/ I can probably live with a sufficiently low-level block layer check.