hi,
as for my other thread posted yesterday (kernel: block nbd0: shutting down sockets), I don't know if the problem is directly related to qemu-nbd but I post on this one because it occurs during its use : thank you for redirecting me if needed.
my system is a Linux (5.10.83) with SystemD (249.7) and Qemu (6.1.0).
when I connect my blank (zeroized) disk /dev/sdb to /dev/nbd0 and disconnect it the next moment, I get I/O error messages even though nothing has been done between these two moments on the disk or on the nbd node (no process such as udisk, no automatic mounting, etc...).
qemu-nbd -r -s -f raw -c /dev/nbd0 /dev/sdb
# some seconds
qemu-nbd -d /dev/nbd0
and in journalctl :
block nbd0: NBD_DISCONNECT
block nbd0: Disconnected due to user request.
blk_update_request: I/O error, dev nbd0, sector 524160 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 0
blk_update_request: I/O error, dev nbd0, sector 524160 op 0x0:(READ) flags 0x0 phys_seg 8 prio class 0
Buffer I/O error on dev nbd0, logical block 524160, async page read
Buffer I/O error on dev nbd0, logical block 524161, async page read
Buffer I/O error on dev nbd0, logical block 524162, async page read
Buffer I/O error on dev nbd0, logical block 524163, async page read
Buffer I/O error on dev nbd0, logical block 524164, async page read
Buffer I/O error on dev nbd0, logical block 524165, async page read
Buffer I/O error on dev nbd0, logical block 524166, async page read
Buffer I/O error on dev nbd0, logical block 524167, async page read
why these I/O errors occur (blk_update_request) ? especially since they are not systematic (some disconnections occur without error).
regards, lacsaP.