Potential deadlock: frozen threads found

It seems that the following threads have not changed their stack for more than 10 seconds.
These threads are possibly (but not necessarily!) in a deadlock or hung.

+-------------------------------------------------------------------------------------------------------------------------------------------+
|                                                                   Name                                                                    |
+-------------------------------------------------------------------------------------------------------------------------------------------+
|  +---Hibernate Search sync consumer thread for index org.openmrs.ConceptComplex Frozen for at least 52m 16s <Ignore a false positive>     |
|  | |                                                                                                                                      |
|  | +---sun.misc.Unsafe.park(boolean, long) Unsafe.java (native)                                                                           |
|  | |                                                                                                                                      |
|  | +---java.util.concurrent.locks.LockSupport.parkNanos(long) LockSupport.java:338                                                        |
|  | |                                                                                                                                      |
|  | +---org.hibernate.search.backend.impl.lucene.SyncWorkProcessor.parkCurrentThread() SyncWorkProcessor.java:179                          |
|  | |                                                                                                                                      |
|  | +---org.hibernate.search.backend.impl.lucene.SyncWorkProcessor.access$300(SyncWorkProcessor) SyncWorkProcessor.java:37                 |
|  | |                                                                                                                                      |
|  | +---org.hibernate.search.backend.impl.lucene.SyncWorkProcessor$Consumer.run() SyncWorkProcessor.java:149                               |
|  | |                                                                                                                                      |
|  | +---java.lang.Thread.run() Thread.java:750                                                                                             |
|  |                                                                                                                                        |
|  +---Hibernate Search sync consumer thread for index org.openmrs.ConceptName Frozen for at least 52m 19s <Ignore a false positive>        |
|  | |                                                                                                                                      |
|  | +---sun.misc.Unsafe.park(boolean, long) Unsafe.java (native)                                                                           |
|  | |                                                                                                                                      |
|  | +---java.util.concurrent.locks.LockSupport.parkNanos(long) LockSupport.java:338                                                        |
|  | |                                                                                                                                      |
|  | +---org.hibernate.search.backend.impl.lucene.SyncWorkProcessor.parkCurrentThread() SyncWorkProcessor.java:179                          |
|  | |                                                                                                                                      |
|  | +---org.hibernate.search.backend.impl.lucene.SyncWorkProcessor.access$300(SyncWorkProcessor) SyncWorkProcessor.java:37                 |
|  | |                                                                                                                                      |
|  | +---org.hibernate.search.backend.impl.lucene.SyncWorkProcessor$Consumer.run() SyncWorkProcessor.java:149                               |
|  | |                                                                                                                                      |
|  | +---java.lang.Thread.run() Thread.java:750                                                                                             |
|  |                                                                                                                                        |
|  +---Hibernate Search sync consumer thread for index org.openmrs.ConceptNumeric Frozen for at least 52m 16s <Ignore a false positive>     |
|  | |                                                                                                                                      |
|  | +---sun.misc.Unsafe.park(boolean, long) Unsafe.java (native)                                                                           |
|  | |                                                                                                                                      |
|  | +---java.util.concurrent.locks.LockSupport.parkNanos(long) LockSupport.java:338                                                        |
|  | |                                                                                                                                      |
|  | +---org.hibernate.search.backend.impl.lucene.SyncWorkProcessor.parkCurrentThread() SyncWorkProcessor.java:179                          |
|  | |                                                                                                                                      |
|  | +---org.hibernate.search.backend.impl.lucene.SyncWorkProcessor.access$300(SyncWorkProcessor) SyncWorkProcessor.java:37                 |
|  | |                                                                                                                                      |
|  | +---org.hibernate.search.backend.impl.lucene.SyncWorkProcessor$Consumer.run() SyncWorkProcessor.java:149                               |
|  | |                                                                                                                                      |
|  | +---java.lang.Thread.run() Thread.java:750                                                                                             |
|  |                                                                                                                                        |
|  +---Hibernate Search sync consumer thread for index org.openmrs.Drug Frozen for at least 52m 16s <Ignore a false positive>               |
|  | |                                                                                                                                      |
|  | +---sun.misc.Unsafe.park(boolean, long) Unsafe.java (native)                                                                           |
|  | |                                                                                                                                      |
|  | +---java.util.concurrent.locks.LockSupport.parkNanos(long) LockSupport.java:338                                                        |
|  | |                                                                                                                                      |
|  | +---org.hibernate.search.backend.impl.lucene.SyncWorkProcessor.parkCurrentThread() SyncWorkProcessor.java:179                          |
|  | |                                                                                                                                      |
|  | +---org.hibernate.search.backend.impl.lucene.SyncWorkProcessor.access$300(SyncWorkProcessor) SyncWorkProcessor.java:37                 |
|  | |                                                                                                                                      |
|  | +---org.hibernate.search.backend.impl.lucene.SyncWorkProcessor$Consumer.run() SyncWorkProcessor.java:149                               |
|  | |                                                                                                                                      |
|  | +---java.lang.Thread.run() Thread.java:750                                                                                             |
|  |                                                                                                                                        |
|  +---Hibernate Search sync consumer thread for index org.openmrs.PatientIdentifier Frozen for at least 52m 16s <Ignore a false positive>  |
|  | |                                                                                                                                      |
|  | +---sun.misc.Unsafe.park(boolean, long) Unsafe.java (native)                                                                           |
|  | |                                                                                                                                      |
|  | +---java.util.concurrent.locks.LockSupport.parkNanos(long) LockSupport.java:338                                                        |
|  | |                                                                                                                                      |
|  | +---org.hibernate.search.backend.impl.lucene.SyncWorkProcessor.parkCurrentThread() SyncWorkProcessor.java:179                          |
|  | |                                                                                                                                      |
|  | +---org.hibernate.search.backend.impl.lucene.SyncWorkProcessor.access$300(SyncWorkProcessor) SyncWorkProcessor.java:37                 |
|  | |                                                                                                                                      |
|  | +---org.hibernate.search.backend.impl.lucene.SyncWorkProcessor$Consumer.run() SyncWorkProcessor.java:149                               |
|  | |                                                                                                                                      |
|  | +---java.lang.Thread.run() Thread.java:750                                                                                             |
|  |                                                                                                                                        |
|  +---Hibernate Search sync consumer thread for index org.openmrs.PersonAttribute Frozen for at least 52m 16s <Ignore a false positive>    |
|  |                                                                                                                                        |
|  +---Hibernate Search sync consumer thread for index org.openmrs.PersonName Frozen for at least 52m 16s <Ignore a false positive>         |
|  |                                                                                                                                        |
|  +---http-nio-8080-exec-10 Frozen for at least 3m 32s <Ignore a false positive>                                                           |
|  |                                                                                                                                        |
|  +---http-nio-8080-exec-15 Frozen for at least 1m 2s <Ignore a false positive>                                                            |
|  |                                                                                                                                        |
|  +---http-nio-8080-exec-18 Frozen for at least 2m 27s <Ignore a false positive>                                                           |
|  |                                                                                                                                        |
|  +---http-nio-8080-exec-19 Frozen for at least 47s <Ignore a false positive>                                                              |
|  |                                                                                                                                        |
|  +---http-nio-8080-exec-21 Frozen for at least 1m 2s <Ignore a false positive>                                                            |
|  |                                                                                                                                        |
|  +---http-nio-8080-exec-22 Frozen for at least 2m 2s <Ignore a false positive>                                                            |
|  |                                                                                                                                        |
|  +---http-nio-8080-exec-26 Frozen for at least 2m 32s <Ignore a false positive>                                                           |
|  |                                                                                                                                        |
|  +---http-nio-8080-exec-3 Frozen for at least 1m 15s <Ignore a false positive>                                                            |
+-------------------------------------------------------------------------------------------------------------------------------------------+