Just updated a node to current master (+https://github.com/bitcoin/bitcoin/pull/7685), the node ran successfully for a couple of weeks, shortly after updating to current master, I ran in a deadlock assertion:
I think the possible deadlock is not related to the PR which I'm running on top.

```
2016-08-26 07:50:29 POTENTIAL DEADLOCK DETECTED
2016-08-26 07:50:29 Previous lock order was:
2016-08-26 07:50:29  pnode->cs_vRecvMsg  net.cpp:1885 (TRY)
2016-08-26 07:50:29  cs_main  main.cpp:4726
2016-08-26 07:50:29  (1) pfrom->cs_filter  main.cpp:4784
2016-08-26 07:50:29  (2) cs_vSend  net.cpp:2683
2016-08-26 07:50:29 Current lock order is:
2016-08-26 07:50:29  (2) pnode->cs_vSend  net.cpp:1904 (TRY)
2016-08-26 07:50:29  cs_main  main.cpp:6343 (TRY)
2016-08-26 07:50:29  pto->cs_inventory  main.cpp:6563
2016-08-26 07:50:29  (1) pto->cs_filter  main.cpp:6586
```

for (int fileNumber = 0; fileNumber < nLastBlockFile; fileNumber++) {
            nBytesToPrune = vinfoBlockFile[fileNumber].nSize + vinfoBlockFile[fileNumber].nUndoSize;
            if (vinfoBlockFile[fileNumber].nSize == 0)
                continue;
            if (nCurrentUsage + nBuffer < nPruneTarget)  
                break;
            
            if (vinfoBlockFile[fileNumber].nHeightLast > nLastBlockWeCanPrune)
                continue;
            PruneOneBlockFile(fileNumber);
            
            setFilesToPrune.insert(fileNumber);
            nCurrentUsage -= nBytesToPrune;
            count++;
        }
    }
    LogPrint("prune", "Prune: target=%dMiB actual=%dMiB diff=%dMiB max_prune_height=%d removed %d blk/rev pairs\n",
           nPruneTarget/1024/1024, nCurrentUsage/1024/1024,
           ((int64_t)nPruneTarget - (int64_t)nCurrentUsage)/1024/1024,
           nLastBlockWeCanPrune, count);
}
bool CheckDiskSpace(uint64_t nAdditionalBytes)
{
    uint64_t nFreeBytesAvailable = boost::filesystem::space(GetDataDir()).available;
    
    if (nFreeBytesAvailable < nMinDiskSpace + nAdditionalBytes)
        return AbortNode("Disk space is low!", _("Error: Disk space is low!"));
    return true;
}
FILE* OpenDiskFile(const CDiskBlockPos &pos, const char *prefix, bool fReadOnly)