v3:
- Added patch 1 (v2: [1]) since it is a prerequisite for other patches
- Patch 1:
- added virtio_legacy_check_disabled() helper
- moved warning where error was returned [Cornelia]
- Patches 2 & 4:
- forced virtio version 1 only with new machine types
- removed Cornelia's R-b since I changed these patches
v2: https://lists.gnu.org/archive/html/qemu-devel/2020-08/msg04437.html
v1: https://lists.gnu.org/archive/html/qemu-devel/2020-08/msg04373.html
Recently changes in QEMU 5.1 requires to set 'disable-legacy=on'
on vhost-vsock-pci and vhost-user-vsock-pci devices:
$ ./qemu-system-x86_64 ... -device vhost-vsock-pci,guest-cid=5
qemu-system-x86_64: -device vhost-vsock-pci,guest-cid=5:
device is modern-only, use disable-legacy=on
As discussed with Cornelia [2], this series forces virtio version 1
to vhost-vsock-pci, vhost-user-vsock-pci, and vhost-vsock-ccw devices.
virtio-vsock was introduced after the release of VIRTIO 1.0 specifications,
so it should be 'modern-only'.
In addition Cornelia verified that forcing a legacy mode on vhost-vsock-pci
device using x86-64 host and s390x guest, so with different endianness,
produces strange behaviours.
This series should be merged in stable branch since it fixes migration issues
with QEMU 5.1:
- we skip legacy support check in the old machine types (< 5.1)
- we force virtio version 1 for vhost-vsock-pci and vhost-vsock-ccw devices
only in the new machine types (>= 5.1). vhost-user-vsock-pci was introduced
in 5.1 and doesn't support migration, so we forced virtio version 1 in any
case,
Thanks,
Stefano
[1] https://lists.gnu.org/archive/html/qemu-devel/2020-09/msg05312.html
[2] https://lists.gnu.org/archive/html/qemu-devel/2020-08/msg02515.html
Stefano Garzarella (4):
virtio: skip legacy support check on machine types less than 5.1
vhost-vsock-pci: force virtio version 1
vhost-user-vsock-pci: force virtio version 1
vhost-vsock-ccw: force virtio version 1
include/hw/virtio/virtio.h | 2 ++
hw/core/machine.c | 1 +
hw/s390x/vhost-vsock-ccw.c | 12 ++++++++++++
hw/s390x/virtio-ccw.c | 15 ++++++++++++---
hw/virtio/vhost-user-vsock-pci.c | 2 +-
hw/virtio/vhost-vsock-pci.c | 10 +++++++++-
hw/virtio/virtio-pci.c | 14 ++++++++++++--
hw/virtio/virtio.c | 7 +++++++
8 files changed, 56 insertions(+), 7 deletions(-)
--
2.26.2