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
```

{
    if (pos.IsNull())
        return NULL;
    boost::filesystem::path path = GetBlockPosFilename(pos, prefix);
    boost::filesystem::create_directories(path.parent_path());
    FILE* file = fopen(path.string().c_str(), "rb+");
    if (!file && !fReadOnly)
        file = fopen(path.string().c_str(), "wb+");
    if (!file) {
        LogPrintf("Unable to open file %s\n", path.string());
        return NULL;
    }
    if (pos.nPos) {
        if (fseek(file, pos.nPos, SEEK_SET)) {
            LogPrintf("Unable to seek to position %u of %s\n", pos.nPos, path.string());
            fclose(file);
            return NULL;
        }
    }
    return file;
}
FILE* OpenBlockFile(const CDiskBlockPos &pos, bool fReadOnly) {
    return OpenDiskFile(pos, "blk", fReadOnly);
}
FILE* OpenUndoFile(const CDiskBlockPos &pos, bool fReadOnly) {
    return OpenDiskFile(pos, "rev", fReadOnly);
}
boost::filesystem::path GetBlockPosFilename(const CDiskBlockPos &pos, const char *prefix)