Guest environment for DF-5590 verification (2026-10-08)

uname -a:
DragonFly dfbsd 6.5-DEVELOPMENT DragonFly 6.5-DEVELOPMENT #0: Thu Jul  2 06:02:54 UTC 2026     root@dfbsd:/usr/obj/usr/src/sys/X86_64_GENERIC  x86_64

Kernel: X86_64_GENERIC (in-tree build; vga compiled in via `device vga0 at isa?`,
sys/config/X86_64_GENERIC:155; NOT a module — kldstat shows only kernel + usbhci KLDs)

Relevant live state:
  sc0: <System console> on motherboard
  sc0: VGA <16 virtual consoles, flags=0x100>
  isa1: <ISA bus> on isab1
  vgapci0: <VGA-compatible display> mem 0xfebd0000-0xfebd0fff,0xfd000000-0xfdffffff at device 2.0 on pci0
  vgapci0: Boot video device
  vga0: <Generic ISA VGA> at port 0x3c0-0x3df iomem 0xa0000-0xbffff on isa1

  Bochs/QEMU VGA (vendor 0x1234 device 0x1111) — ISA twin (vga0) attaches live
  alongside the PCI one (vgapci0); verify_adapter() write/read test at the
  0xa0000 window passes on this rig.

  /dev/vga0 does not exist (GENERIC does not compile FB_INSTALL_CDEV;
  sys/conf/options:404 — LINT64 only), so the cdev half of the finding is
  compiled out on this guest.

Guest dirtiness at end of verification: none (read-only introspection:
dmesg/devinfo/ls/pciconf/kldstat queries only).