mirror of
https://github.com/tailscale/tailscale.git
synced 2025-12-23 00:56:20 +00:00
d199ecac80
Previously, callers of (*LocalBackend).resetControlClientLocked were supposed to call Shutdown on the returned controlclient.Client after releasing b.mu. In #17804, we started calling Shutdown while holding b.mu, which caused deadlocks during profile switches due to the (*ExecQueue).RunSync implementation. We first patched this in #18053 by calling Shutdown in a new goroutine, which avoided the deadlocks but made TestStateMachine flaky because the shutdown order was no longer guaranteed. In #18070, we updated (*ExecQueue).RunSync to allow shutting down the queue without waiting for RunSync to return. With that change, shutting down the control client while holding b.mu became safe. Therefore, this PR updates (*LocalBackend).resetControlClientLocked to shut down the old client synchronously during the reset, instead of returning it and shifting that responsibility to the callers. This fixes the flaky tests and simplifies the code. Fixes #18052 Signed-off-by: Nick Khyl <nickk@tailscale.com>