Re: CVS commit: src/sys/kern

[Robert Elz <kre%munnari.OZ.AU@localhost>]

    Date:        Fri, 22 Dec 2017 23:22:37 +0700
    From:        Robert Elz <kre%munnari.OZ.AU@localhost>
    Message-ID:  <1080.1513959757%andromeda.noi.kre.to@localhost>

  | where vm was declared as
  | 
  | 	struct vmspace *vm;
  | 
  | but is not otherwise initialised

Well, not quite, I missed this call in ptrce_doio()

	error = proc_vmspace_getref(l->l_proc, vm);

where proc_vmspace_getref() is ...

        if ((p != curproc && (p->p_sflag & PS_WEXIT) != 0) ||
            (p->p_vmspace->vm_refcnt < 1)) { /* XXX */
                return EFAULT;
        }

        uvmspace_addref(p->p_vmspace);
        *vm = p->p_vmspace;

which is much more complex than the old (and now current way) which
more or less boils down to

	*vm = proc0.p_vmspace;

(except there is no vm to * ... bt for easier comparison.)

The EFAULT that is returned there is probably the one Kamil mentioned.

kre