I think the metadata size check is too strict. Commands where the metadata size is too small should result in errors but when the metadata size is larger than needed they should still go through. In any case, I tested this patch on a QEMU NVMe device (which supports PI by default). I formatted the device with a 512+16 lbaf with a separate buffer for metadata: nvme format /dev/ng0n1 -m 0 -i 1 -p 0 --lbaf 2 --force Using the latest fio I wrote some data to it: ./fio --name=difdix --ioengine=io_uring_cmd --cmd_type=nvme \ --filename=/dev/ng0n1 --rw=write --bs=512 --md_per_io_size=16 --pi_act=1 \ --pi_chk=APPTAG --apptag=0x8888 --apptag_mask=0xFFFF --number_ios=128 Then I wrote a small program to read 4096 bytes from the device with only a 16-byte (instead of 64-byte) metadata buffer. Without this patch the kernel crashes. With the patch the read fails with an error message in the kernel log. Tested-by: Vincent Fu <vincent.fu@xxxxxxxxxxx>
