Re: Boot VM from a zvol using qemu and nvmm?

[Greg Troxel <gdt%lexort.com@localhost>]

I have a xen system with images on zfs, and have also been able to boot
GENERIC instead of xen, and then run qemu, using the same image zvols.

from my qemu script

IMG=/dev/zvol/rdsk/tank0/vm/n9-amd64

/usr/pkg/bin/qemu-system-x86_64 \
    -m 3000 \
    -vnc 127.0.0.1:${vnc_port} \
    -nographic \
    -drive format=raw,file=${IMG},if=none,id=hd0 \
    -device virtio-blk-pci,drive=hd0 \
    -netdev tap,id=${IFACE},ifname=${IFACE},script=no \
    -device virtio-net-pci,netdev=${IFACE},mac=${MAC}


and

$ zfs get all tank0/vm/n9-amd64
tank0/vm/n9-amd64  volblocksize          8K                     -

I am fuzzy on the blocksize issues, and haven't tried to do anything
special.  My pool is on a disklabel partition on a 1T ssd, with the
partition and zvol created:

2021-02-11.19:27:50 zpool create pool1 /dev/wd0f
2023-07-08.08:54:25 zfs create -p -V 32G tank0/vm/n9-amd64

according to `zpool history`.  All of my zvols are the volblocksize 8K.