fix(srv6): synchronize pub/sub handler registrations#31
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RegisterHandler appends to pubSubHandlerRegistrations and SendEvent ranges it with no lock. The srv6egress SR-policy-liveness handler is registered after the route/prefix/peer/routing producers have started calling SendEvent, so the concurrent append+range is a data race that can drop the registration. Guard the slice with an RWMutex; SendEvent snapshots under the read lock and sends off-lock so a slow consumer can't stall a concurrent RegisterHandler.
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What
RegisterHandlerappends topubSubHandlerRegistrationsandSendEventranges it with no lock. The srv6egress SR-policy-liveness handler is registered after the route/prefix/peer/routing producers have started callingSendEvent, so the concurrent append+range is a data race that can drop the registration (steering liveness silently never wired).Fix
Guard the slice with an
RWMutex.SendEventsnapshots under the read lock and sends off-lock, so a slow consumer can't stall a concurrentRegisterHandler.Review finding
Low (concurrency) C2.
Test
GOOS=linux go vet ./calico-vpp-agent/common/...green.