DF-2505 fix validation run -- PATCHED kernel 'DragonFly 6.5-DEVELOPMENT #1: Thu Oct 15 23:37:29 UTC 2026'
(fix.diff applied; rig rebuilt against patched /usr/src; all four tests re-run)

0
  BCA: s=0xfffff8008dbe5200 sizeof(struct dvd_struct)=2060 s->length=188 (drive-claimed, ntohs)
  data window [0,188): payload 0xC3 x188, guard-marker 0xAA x0, other-nonzero x0
  destination side: 0/10 0xBB guard chunks after s smashed
  NOTE: no 0xAA beyond 188 (markers absent -- placement missed?); non-payload-nonzero x0
last_rc=0


  BCA: s=0xfffff8008dbe4000 sizeof(struct dvd_struct)=2060 s->length=188 (drive-claimed, ntohs)
  data window [0,188): payload 0xC3 x188, guard-marker 0xAA x0, other-nonzero x0
  destination side: 0/10 0xBB guard chunks after s smashed
  NOTE: no 0xAA beyond 188 (markers absent -- placement missed?); non-payload-nonzero x0
last_rc=0


  data window [0,2048): payload 0xC3 x2048, guard-marker 0xAA x0, other-nonzero x0
  destination side: 0/10 0xBB guard chunks after s smashed
  NOTE: no 0xAA beyond 2048 (markers absent -- placement missed?); non-payload-nonzero x0
gave up after 6 tries (kmalloc placement kept missing)
last_rc=0


production acd_read_structure() rc=0; d=0xfffff8004f2308d0 (want hole 0xfffff8004f2308d0, HIT) transfer 192 bytes; s=0xfffff80118620000 (2060-byte M_IOCTLOPS, big container)
  BCA: s=0xfffff80118620000 sizeof(struct dvd_struct)=2060 s->length=188 (drive-claimed, ntohs)
  data window [0,188): payload 0xC3 x188, guard-marker 0xAA x0, other-nonzero x0
  NOTE: no 0xAA beyond 188 (markers absent -- placement missed?); non-payload-nonzero x0
last_rc=0