Quoting John Kohl,

> >Number:         2065
> >Category:       port-i386
> >Synopsis:       i386 calls tss_free() in a context with no curproc, leading to faults

> I'm not sure this is quite the right thing, but it seems like we need to
> get curproc set to something acceptable before calling tss_free.  I
> haven't tested this yet (I wanted to file the bug so that other folks
> will be aware and might figure out how to fix it), but my first guess
> is:
[...]

See my PR port-i386/1964 about the same bug. I actually (quickly) tried the
same patch as you propose here, but I didn't work as far as I remember.

- Frank