crimson/osd: fix race between AllReplicasRecovered and DeferRecovery
Fixes a crash where AllReplicasRecovered event arrives at NotRecovering
state due to async event delivery race with DeferRecovery preemption.
The issue occurs when:
1. Recovery completes and AllReplicasRecovered is queued asynchronously
2. A higher priority operation (e.g., client I/O) triggers AsyncReserver
to preempt recovery, posting DeferRecovery event
3. DeferRecovery is processed first, transitioning PG to NotRecovering
4. AllReplicasRecovered arrives at wrong state → crash with "bad state
machine event" because NotRecovering doesn't handle it
The fix follows Classic OSD's approach in PrimaryLogPG::start_recovery_ops():
clear PG_STATE_RECOVERING before posting recovery completion events. This
makes the existing safety check in PeeringState::Recovering::react() work:
when DeferRecovery arrives and sees !state_test(PG_STATE_RECOVERING), it
discards itself, preventing the state transition that would cause the crash.
projects / ceph.git / commit