the shr mount is linked into the Mhead with m->to initially nil. only
after the the server has been attached is m->to set. just check for
it in createdir().
closechanq() is unable to fork a new closeproc when palloc
is locked. so we spawn a closeproc early in chandevinit()
and make sure theres always one process arround to handle
the queue.
catch potential interrupt error from kproc(). this can happen when
we run out of processes, then newproc() will call rsrcwait()
which does tsleep(). if the process gets a note, this might
raise a interrupt error.
kstrcpy() did not null terminate for < 4 byte buffers. fixed,
but i dont think there is any case where this can happen in
practice.
always set malloctag in kstrdup(), cleanup.
always use ERRMAX bounded kstrcpy() to set up->errstr, q->err
and note[]->msg. paranoia.
instead of silently truncating interface name in netifinit(),
panic the kernel if interface name is too long as this case
is clearly a mistake.
panic kernel when filename is too long for addbootfile() in
devroot. this might happen if your kernel configuration is
messed up.
