Fix a jetStream / jsAccount lock ordering violation#7710
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neilalexander merged 1 commit intomainfrom Jan 9, 2026
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| // Add created timestamp used for the store, must match that of the stream assignment if it exists. | ||
| if sa != nil { | ||
| js.mu.RLock() | ||
| mset.created = sa.Created |
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I assume this is safe because sa.Created is a special-case field whose value never changes, if so it might be worth adding a comment to that effect.
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Yes, the field appears to be immutable.
Running BenchmarkJetStreamCreate under -race shows no problems.
(BenchmakrJetStreamCreate would reliably fall into the deadlock execution)
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Added a comment in the code to clarify that.
Method `addStreamWithAssignment` could cause a deadlock when
acquiring the jetStream lock while holding the jsAccount lock,
a lock ordering violation.
This would cause a deadlock when attempting to shutdown and a
a stream was created concurrrently. Easiliy reproduced when
running `BenchmarkJetStreamCreate` benchmark.
The jetstream lock was acquired to protect the following
assignment:
```
mset.create = sa.Created
```
It appears unnecessary to lock jetstream for that, so the fix
removes the locking.
Signed-off-by: Daniele Sciascia <daniele@nats.io>
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This was referenced Jan 15, 2026
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Method
addStreamWithAssignmentcould cause a deadlock when acquiring the jetStream lock while holding the jsAccount lock, a lock ordering violation.This would cause a deadlock when attempting to shutdown and a a stream was created concurrrently. Easiliy reproduced when running
BenchmarkJetStreamCreatebenchmark.The jetstream lock was acquired to protect the following assignment:
It appears unnecessary to lock jetstream for that, so the fix removes the locking.
Signed-off-by: Daniele Sciascia daniele@nats.io