Can't find subsystem in Qsys

[Altera_Forum]

I've got a hierarchical subblock in Qsys (15.1, 64-bit Linux) that after much debugging I'm finally ready to incorporate into my higher level design. No luck; it's not turning up in the IP window. All the other .qsys files in the same directory do, and I have no .ipx files anywhere. 

 The screenshot's pretty clear. All of the .qsys files in ./src/cores are appearing under System except for dma.qsys. I checked the .qsys files, and dma.qsys is the same as all the others; UTF-8 encoded, LF only for EOL marker, identical <component> tags.

[Altera_Forum]

Finally figured it out. It didn't like the file name. dma apparantly conflicts with something else in the world, and so Qsys simply chose not to show it to me. No warning message, no nothing. Rename the file to dma2 and it works. Ugh.