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For this to work, we need to reset >> the device ownership on the source side by calling RESET_OWNER, and then >> claim it on the dest side by calling SET_OWNER. We expect not to lose any >> AF_VSOCK connection while this happens. >> >> To that end, unlike the release path, RESET_OWNER keeps the guest CID >> hashed: established connections survive, and host sends issued while >> the device is between owners simply stay on send_pkt_queue until the >> next device start drains them. >> >> Since the device stays reachable through the CID hash, the lockless >> send/cancel paths can race with the worker teardown in >> vhost_workers_free(). The previous commit ("vhost: synchronize with >> RCU readers when freeing workers") makes that safe. >> >> Signed-off-by: Pavel Tikhomirov >> Signed-off-by: Andrey Drobyshev >> --- >> drivers/vhost/vsock.c | 32 ++++++++++++++++++++++++++++++++ >> 1 file changed, 32 insertions(+) > > I thought I had already reviewed this, but anyway: > > Reviewed-by: Stefano Garzarella > I explicitly dropped your R-b since the logic was slightly altered as noted in the cover letter: Patch 5: add 'sync' param to vhost_dev_reset_owner() call. Thank you, Andrey