DF-0860 leaked heap bytes (arglen=128, run on unpatched 6.5-DEVELOPMENT #0)
Three consecutive runs as root. The leaked region (bytes 52..179 of the reply)
is genuine kernel heap residue: contains canonical kernel pointers and residual
strings from other allocations. Non-zero byte counts vary across fresh boots.

run.log (leak_bytes=128): non-zero=84/128, pointers 0xfffff800_4f1643c0 etc,
  ASCII "rcng_automountd","disabled","/usr"
run.2.log (leak_bytes=128): non-zero=84/128, same slab neighbourhood
run.3.log (leak_bytes=64):  non-zero=40/64
baseline_run.log (post-reset reconfirm): non-zero=3/128, leading ASCII "hcp"
  (different residue after the vm.sh reset wiped the slab neighbourhood)