Tested the current series of patches, mixed with patches from series [1] and [2], and the virtio-net regression tests passed. I also tested local VM migration under multiple NIC queues enabled and disabled, it also passed.
[1] https://patchwork.ozlabs.org/project/qemu-devel/cover/[email protected]/ [2] https://patchwork.ozlabs.org/project/qemu-devel/cover/[email protected]/ Tested-by: Lei Yang <[email protected]> On Wed, Sep 3, 2025 at 9:37 PM Vladimir Sementsov-Ogievskiy <[email protected]> wrote: > > Hi all! > > Here is a new migration capability "local-tap", which > allows local migration of TAP device, including its properties > and open fds. > > With this new option, management software doesn't need to > initialize new TAP and do a switch to it. Nothing should be > done around virtio-net in local migration: it just migrates > and continues to use same TAP device. So we avoid extra logic > in management software, extra allocations in kenel (for new TAP), > and corresponding extra delay in migration downtime. > > Note that patch 07 is reused from > [PATCH 00/33] vhost-user-blk: live-backend local migration > to not create extra dependency on a big series. > > Based on [PATCH v3 00/19] TAP initialization refactoring, or in other > words: > Based-on: <[email protected]> > > Vladimir Sementsov-Ogievskiy (8): > net/tap: add some trace points > net/tap: keep exit notifier only when downscript set > net/tap: refactor net_tap_setup_vhost() > qapi: add interface for local TAP migration > net/tap: implement interfaces for local migration > virtio-net: support local tap migration > test/functional: exec_command_and_wait_for_pattern: add vm arg > tests/functional: add test_x86_64_tap_fd_migration > > hw/net/virtio-net.c | 100 ++++- > include/hw/virtio/virtio-net.h | 2 + > include/net/tap.h | 4 + > migration/options.c | 7 + > migration/options.h | 1 + > net/tap.c | 323 ++++++++++++---- > net/trace-events | 7 + > qapi/migration.json | 9 +- > qapi/net.json | 12 +- > tests/functional/qemu_test/cmd.py | 7 +- > .../test_x86_64_tap_fd_migration.py | 347 ++++++++++++++++++ > 11 files changed, 734 insertions(+), 85 deletions(-) > create mode 100644 tests/functional/test_x86_64_tap_fd_migration.py > > -- > 2.48.1 >
