[Qemu-devel] [PATCH 0/9] virtio-serial fixes, ABI updates

[Amit Shah]

Hello,

This series fixes a few issues pointed out by Avi and Juan. Avi
pointed out we should do full scatter/gather processing of guest data
even if current (well-behaved) guests don't send multiple iovs per
element.

Juan pointed out a few migration-related bugs.

In handling the migration fixes, I noticed hot-plug/unplug isn't
handled perfectly for the migration case: ports are enumerated and the
port numbering has to be consistent with the guest's numbering. If
there's a mismatch, control messages meant for one port could be
interpreted for another.

To solve this issue, I go back to maintaining a bitmap in the config
space for active ports. Hot-plug and unplug can be added easily via
the config space as a result.

The kernel driver has to be changed as well so that the changes are in
sync with the changes here.

I've tested these patches on my test suite that tests for correctness
and also hot-plug/unplug cases and fixes presented here.

Amit Shah (9):
  virtio-serial-bus: save/load: Ensure target has enough ports
  virtio-serial-bus: save/load: Ensure nr_ports on src and dest are
    same.
  virtio-serial: save/load: Ensure we have hot-plugged ports
    instantiated
  virtio-serial: Handle scatter-gather buffers for control messages
  virtio-serial: Handle scatter/gather input from the guest
  virtio-serial: Remove redundant check for 0-sized write request
  virtio-serial: Update copyright year to 2010
  virtio-serial-bus: Use a bitmap in virtio config space for active
    ports
  virtio-serial-bus: Let the guest know of host connection changes
    after migration

 hw/virtio-console.c    |    4 +-
 hw/virtio-serial-bus.c |  205 ++++++++++++++++++++++++++++++++++++------------
 hw/virtio-serial.h     |    8 +-
 3 files changed, 161 insertions(+), 56 deletions(-)