Bug 31367

Copyright (c) 1992-2001 The FreeBSD Project.
Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994    
The Regents of the University of California. All rights reserved.
FreeBSD 4.4-RELEASE #0: Sun Oct  7 02:13:45 EEST 2001
root@:/usr/src/sys/compile/KRULE
Timecounter "i8254"  frequency 1193182 Hz
CPU: AMD Duron(tm) processor (704.73-MHz 686-class CPU)
Origin = "AuthenticAMD"  Id = 0x631  Stepping = 1
Features=0x183f9ff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,MMX,FXSR>
AMD Features=0xc0440000<<b18>,AMIE,DSP,3DNow!>
real memory  = 268369920 (262080K bytes)
config> en apm0
config> f apm0 0x31
avail memory = 257294336 (251264K bytes)
Preloaded elf kernel "kernel" at 0xc03f1000.
Preloaded userconfig_script "/boot/kernel.conf" at 0xc03f109c.
VESA: v3.0, 4096k memory, flags:0x1, mode table:0xc0376fe2 (1000022)
VESA: NVidia
Pentium Pro MTRR support enabled
md0: Malloc disk
Using $PIR table, 7 entries at 0xc00fdf00
apm0: <APM BIOS> on motherboard
apm: found APM BIOS v1.2, connected at v1.2
npx0: <math processor> on motherboard
npx0: INT 16 interface
pcib0: <Host to PCI bridge> on motherboard
pci0: <PCI bus> on pcib0
pcib1: <PCI to PCI bridge (vendor=1106 device=8305)> at device 1.0 on pci0
pci1: <PCI bus> on pcib1
pci1: <NVidia Riva TNT2 graphics accelerator> at 0.0 irq 10
isab0: <VIA 82C686 PCI-ISA bridge> at device 7.0 on pci0
isa0: <ISA bus> on isab0
atapci0: <VIA 82C686 ATA100 controller> port 0xd000-0xd00f at device 7.1 on pci0
ata0: at 0x1f0 irq 14 on atapci0
ata1: at 0x170 irq 15 on atapci0
uhci0: <VIA 83C572 USB controller> port 0xd400-0xd41f irq 0 at device 7.2 on pci0
pci_cfgintr_virgin: using routable PCI-only interrupt 5
pci_cfgintr: ROUTE_INTERRUPT failed.
usb0: <VIA 83C572 USB controller> on uhci0
usb0: USB revision 1.0
uhub0: VIA UHCI root hub, class 9/0, rev 1.00/1.00, addr 1
uhub0: 2 ports with 2 removable, self powered
chip1: <VIA 82C686 ACPI interface> at device 7.4 on pci0
pcm0: <Creative EMU10K1> port 0xdc00-0xdc1f irq 5 at device 9.0 on pci0
xl0: <3Com 3c905C-TX Fast Etherlink XL> port 0xe400-0xe47f mem 0xe7000000-0xe700007f irq 11 at device 11.0 on pci0
xl0: Ethernet address: 00:50:da:46:e8:80
miibus0: <MII bus> on xl0
xlphy0: <3c905C 10/100 internal PHY> on miibus0
xlphy0:  10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
orm0: <Option ROM> at iomem 0xc0000-0xca7ff on isa0
fdc0: <NEC 72065B or clone> at port 0x3f0-0x3f5,0x3f7 irq 6 drq 2 on isa0
fdc0: FIFO enabled, 8 bytes threshold
fd0: <1440-KB 3.5" drive> on fdc0 drive 0
atkbdc0: <Keyboard controller (i8042)> at port 0x60,0x64 on isa0
atkbd0: <AT Keyboard> flags 0x1 irq 1 on atkbdc0
kbd0 at atkbd0
psm0: <PS/2 Mouse> irq 12 on atkbdc0
psm0: model IntelliMouse, device ID 3
vga0: <Generic ISA VGA> at port 0x3c0-0x3df iomem 0xa0000-0xbffff on isa0
sc0: <System console> at flags 0x100 on isa0
sc0: VGA <16 virtual consoles, flags=0x300>
sio0 at port 0x3f8-0x3ff irq 4 on isa0
sio0: type 16550A
sio1 at port 0x2f8-0x2ff irq 3 on isa0
sio1: type 16550A
ppc0: <Parallel port> at port 0x378-0x37f irq 7 on isa0
ppc0: SMC-like chipset (ECP/EPP/PS2/NIBBLE) in COMPATIBLE mode
ppc0: FIFO with 16/16/8 bytes threshold
plip0: <PLIP network interface> on ppbus0
lpt0: <Printer> on ppbus0
lpt0: Interrupt-driven port
ppi0: <Parallel I/O> on ppbus0
IPsec: Initialized Security Association Processing.
ad0: 29311MB <Maxtor 5T030H3> [59554/16/63] at ata0-master UDMA100
acd0: CDROM <FX4820T> at ata1-master using PIO4
Mounting root from ufs:/dev/ad0s2a

And system freezen. Rebooting not helps. 
Also system freezen while booting from original CD-ROM REALESE-4.4, and  REALESE-4.4 floppies !

Fix: 

Fix kernel 4.4 source !
How-To-Repeat: Boot system on 686b + KT133A motherboard with 4.4-REALESE kernel