Comment # 6 on bug 1200162 from Luis Henriques

(In reply to S������awomir Lach from comment #5)
> Attached, but I do not known if it contains useful information.

Actually, it does.  I think 'lsof' doesn't work the way you expect it to.

It looks like the 1st thing lsof is doing on your 2nd call ("lsof /etc") is to
walk through all the mount points on your system and it is blocking in your
filesystem's mount point "/vsimple-ipc" (see the end of the strace output).

So, I don't think this is a fuse issue but something missing/bogus in your
implementation.  And yes, "lsof" is not very intuitive -- everytime I need to
use it I need to spend a lot of time going through it's manpage several times.