On Fri, Jul 18, 2025 at 4:48 PM Lei Yang <leiy...@redhat.com> wrote: > > Hi Steve > > I tested your patch which hit a problem under enable/disable nic mq > state(The full test scenario is live migration vm at local under > enable/disable vm nic mq state): > Run command: /qemu-img info /home/images/vm1.qcow2 --output=json > Error info: qemu-img: Could not open '/home/images/vm1.qcow2': Failed > to get shared "write" lock > > In the same environment if I remove the enable/disable nic mq steps, > it can work well. > > Note: This issue has not been reproduced 100%, but in order to confirm > this is really a bug, I test the following: > 1. Live migration vm at local under enable/disable nic mq state: 3/5 > reproduce ratio > 2. Only live migration 5 times are all passed. > After double confirm tests, the above mentioned problem should not be related to the current series of patches, because I also hit this problem after multiple tests using the upstream master branch.
Tested-by: Lei Yang <leiy...@redhat.com> > Thanks > Lei > > On Fri, Jul 18, 2025 at 4:48 AM Steve Sistare <steven.sist...@oracle.com> > wrote: > > > > Tap and vhost devices can be preserved during cpr-transfer using > > traditional live migration methods, wherein the management layer > > creates new interfaces for the target and fiddles with 'ip link' > > to deactivate the old interface and activate the new. > > > > However, CPR can simply send the file descriptors to new QEMU, > > with no special management actions required. The user enables > > this behavior by specifing '-netdev tap,cpr=on'. The default > > is cpr=off. > > > > Steve Sistare (8): > > migration: stop vm earlier for cpr > > migration: cpr setup notifier > > vhost: reset vhost devices for cpr > > cpr: delete all fds > > Revert "vhost-backend: remove vhost_kernel_reset_device()" > > tap: common return label > > tap: cpr support > > tap: postload fix for cpr > > > > qapi/net.json | 5 +- > > include/hw/virtio/vhost.h | 1 + > > include/migration/cpr.h | 3 +- > > include/net/tap.h | 1 + > > hw/net/virtio-net.c | 20 +++++++ > > hw/vfio/device.c | 2 +- > > hw/virtio/vhost-backend.c | 6 ++ > > hw/virtio/vhost.c | 32 +++++++++++ > > migration/cpr.c | 24 ++++++-- > > migration/migration.c | 38 ++++++++----- > > net/tap-win32.c | 5 ++ > > net/tap.c | 141 > > +++++++++++++++++++++++++++++++++++----------- > > 12 files changed, 223 insertions(+), 55 deletions(-) > > > > -- > > 1.8.3.1 > > > >
