Re: [Libguestfs] nbdkit error: "write reply: NBD_CMD_WRITE: Broken pipe"

On May 03 2022, rjones at redhat.com (Richard W.M. Jones) wrote: >> So I tried to reproduce this, and noticed something odd. It seems I can >> disconnect the nbd device (nbd-client -d) while there are still requests >> in flight: >> >> May 02 15:20:50 vostro.rath.org kernel: nbd1: detected capacity change from 0 to 52428800 >> May 02 15:20:50 vostro.rath.org kernel: block nbd1: NBD_DISCONNECT >> May 02 15:20:50 vostro.rath.org kernel: block nbd1: Disconnected due to user request. >> May 02 15:20:50 vostro.rath.org kernel: block nbd1: shutting down sockets >> May 02 15:20:50 vostro.rath.org kernel: I/O error, dev nbd1, sector 776 op 0x0:(READ) >> flags 0x80700 phys_seg 29 prio class 0 >> May 02 15:20:50 vostro.rath.org kernel: I/O error, dev nbd1, sector 776 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 0 >> May 02 15:20:50 vostro.rath.org kernel: Buffer I/O error on dev nbd1, logical block 97, async page read >> May 02 15:20:50 vostro.rath.org kernel: block nbd1: Attempted send on invalid socket >> May 02 15:20:50 vostro.rath.org kernel: I/O error, dev nbd1, sector 0 op 0x1:(WRITE) flags 0x800 phys_seg 0 prio class 0 >> May 02 15:20:50 vostro.rath.org kernel: block nbd1: Attempted send on invalid socket >> May 02 15:20:50 vostro.rath.org kernel: I/O error, dev nbd1, sector 0 op 0x1:(WRITE) flags 0x800 phys_seg 0 prio class 0 >> >> This was generated by running: >> >> $ nbd-client localhost /dev/nbd1 && mkfs.ext4 /dev/nbd1 && nbd-client -d >> /dev/nbd1 >> >> Is that expected behavior? > > It's a bit unexpected to me. Adding Wouter to the thread - he might > have an idea here, especially if there's a way to have "nbd-client -d" > wait for pending requests to finish before disconnecting. > > I don't use the kernel client very much myself. We mostly use either > libnbd or the qemu client. Did you Cc Wouter to your email? I didn't see a Cc header, but perhaps this was stripped by the mailing list software? Or is there a more appropriate list where I could follow-up on this?