On a -current (as of yesterday) 386, my mouse suddenly stopped.  I'm 
running X 4.2.0, with a PS2 mouse.  I have ACPI with all the options 
enabled for this machine, mostly to see what they do:

# Advanced Control and Power Interface

# This option can be used to retrieve CPU and APIC information.
# that I/O APICs can be used if ACPI is enabled below.
# To use the I/O APIC(s), enable the ioapic line above.
options         MPACPI

acpi0           at mainbus0
options         ACPI_PCI_FIXUP          # PCI interrupt routing via ACPI
options         ACPI_ACTIVATE_DEV       # If set, activate inactive devices

# ACPI devices 
acpiacad*       at acpi?                # ACPI AC Adapter
acpibat*        at acpi?                # ACPI Battery
acpibut*        at acpi?                # ACPI Button
acpiec*         at acpi?                # ACPI Embedded Controller
acpilid*        at acpi?                # ACPI Lid Switch
acpitz*         at acpi?                # ACPI Thermal Zone

Restarting X brought it back.

NetBSD 1.6M (CHALLENGER.acpi) #2: Wed Jan 22 20:58:12 EST 2003
    root@challenger.research.att.com:/usr/src/sys/arch/i386/compile/CHALLENGER.acpi
total memory = 255 MB
avail memory = 229 MB
using 3296 buffers containing 13184 KB of memory
BIOS32 rev. 0 found at 0xf0f50
mainbus0 (root)
cpu0 at mainbus0: (uniprocessor)
cpu0: AMD Athlon Model 4 (Thunderbird) (686-class), 756.79 MHz, id 0x642
cpu0: features c1c7f9ff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,SEP,MTRR>
cpu0: features c1c7f9ff<PGE,MCA,CMOV,PAT,PSE36,PN,MMXX,MMX>
cpu0: features c1c7f9ff<FXSR,3DNOW2,3DNOW>
cpu0: I-cache 64 KB 64b/line 2-way, D-cache 64 KB 64b/line 2-way
cpu0: L2 cache 256 KB 64b/line 16-way
cpu0: ITLB 16 4 KB entries fully associative, 8 4 MB entries fully associative
cpu0: DTLB 24 4 KB entries fully associative, 8 4 MB entries 4-way
cpu0: 8 page colors
acpi0 at mainbus0
acpi0: X/RSDT: OemId <ASUS  ,A7Pro   ,30303031>, AslId <MSFT,31313031>
acpi0: SCI interrupting at int 9
acpi0: fixed-feature power button present
ACPI Object Type 'Processor' (0x0c) at acpi0 not configured
acpibut0 at acpi0 (PNP0C0C): ACPI Power Button
PNP0C01 [System Board] at acpi0 not configured
PNP0C0F [PCI interrupt link device] at acpi0 not configured
PNP0C0F [PCI interrupt link device] at acpi0 not configured
PNP0C0F [PCI interrupt link device] at acpi0 not configured
PNP0C0F [PCI interrupt link device] at acpi0 not configured
PNP0A03 [PCI Bus] at acpi0 not configured
PNP0C02 [Plug and Play motherboard register resources] at acpi0 not configured
PNP0C02 [Plug and Play motherboard register resources] at acpi0 not configured
PNP0000 [AT Interrupt Controller] at acpi0 not configured
PNP0200 [AT DMA Controller] at acpi0 not configured
PNP0100 [AT Timer] at acpi0 not configured
PNP0B00 [AT Real-Time Clock] at acpi0 not configured
PNP0800 [AT-style speaker sound] at acpi0 not configured
npx1 at acpi0 (PNP0C04)
npx1: io 0xf0-0xff irq 13
npx1: using exception 16
fdc1 at acpi0 (PNP0700)
fdc1: io 0x3f2-0x3f5,0x3f7 irq 6 drq 2
fd0 at fdc1 drive 0: density unknown
lpt0 at acpi0 (PNP0401)
lpt0: io 0x378-0x37f,0x778-0x77b irq 7 drq 3
com0 at acpi0 (PNP0501-1)
com0: io 0x3f8-0x3ff irq 4
com0: ns16550a, working fifo
com1 at acpi0 (PNP0501-2)
com1: io 0x2f8-0x2ff irq 3
com1: ns16550a, working fifo
pckbc1 at acpi0 (PNP0303): kbd port
pckbc1: io 0x60,0x64 irq 1
pckbc2 at acpi0 (PNP0F13): aux port
pckbc2: irq 12
pckbd0 at pckbc1 (kbd slot)
pckbc1: using irq 1 for kbd slot
wskbd0 at pckbd0: console keyboard
pms0 at pckbc1 (aux slot)
pckbc1: using irq 12 for aux slot
wsmouse0 at pms0 mux 0
pci0 at mainbus0 bus 0: configuration mode 1
pci0: i/o space, memory space enabled, rd/line, rd/mult, wr/inv ok
pchb0 at pci0 dev 0 function 0
pchb0: VIA Technologies VT8363 KT133 System Controller (rev. 0x02)
agp0 at pchb0: aperture at 0xe4000000, size 0x10000000
ppb0 at pci0 dev 1 function 0: VIA Technologies VT8363 KT133 PCI to AGP Bridge (rev. 0x00)
pci1 at ppb0 bus 1
pci1: i/o space, memory space enabled
vga1 at pci1 dev 0 function 0: ATI Technologies Rage XL (AGP) (rev. 0x27)
wsdisplay0 at vga1 kbdmux 1: console (80x25, vt100 emulation), using wskbd0
wsmux1: connecting to wsdisplay0
pcib0 at pci0 dev 4 function 0
pcib0: VIA Technologies VT82C686A (Apollo KX133) PCI-ISA Bridge (rev. 0x22)
pciide0 at pci0 dev 4 function 1: VIA Technologies VT82C686A (Apollo KX133) ATA66 controller
pciide0: bus-master DMA support present
pciide0: primary channel configured to compatibility mode
wd0 at pciide0 channel 0 drive 0: <IBM-DTLA-307075>
wd0: drive supports 16-sector PIO transfers, LBA addressing
wd0: 73308 MB, 16383 cyl, 16 head, 63 sec, 512 bytes/sect x 150136560 sectors
wd0: 32-bit data port
wd0: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 5 (Ultra/100)
pciide0: primary channel interrupting at irq 14
wd0(pciide0:0:0): using PIO mode 4, Ultra-DMA mode 4 (Ultra/66) (using DMA data transfers)
pciide0: secondary channel configured to compatibility mode
atapibus0 at pciide0 channel 1: 2 targets
cd0 at atapibus0 drive 0: <LTN485, , KQ01> cdrom removable
cd0: 32-bit data port
cd0: drive supports PIO mode 4, DMA mode 2
cd1 at atapibus0 drive 1: <Hewlett-Packard CD-Writer Plus 9500, YM5CJ58VA3, 1.0e> cdrom removable
cd1: 32-bit data port
cd1: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 2 (Ultra/33)
pciide0: secondary channel interrupting at irq 15
cd0(pciide0:1:0): using PIO mode 4, DMA mode 2 (using DMA data transfers)
cd1(pciide0:1:1): using PIO mode 4, Ultra-DMA mode 2 (Ultra/33) (using DMA data transfers)
uhci0 at pci0 dev 4 function 2: VIA Technologies VT83C572 USB Controller (rev. 0x10)
uhci0: interrupting at irq 5
usb0 at uhci0: USB revision 1.0
uhub0 at usb0
uhub0: VIA Technologies UHCI root hub, class 9/0, rev 1.00/1.00, addr 1
uhub0: 2 ports with 2 removable, self powered
uhci1 at pci0 dev 4 function 3: VIA Technologies VT83C572 USB Controller (rev. 0x10)
uhci1: interrupting at irq 5
usb1 at uhci1: USB revision 1.0
uhub1 at usb1
uhub1: VIA Technologies UHCI root hub, class 9/0, rev 1.00/1.00, addr 1
uhub1: 2 ports with 2 removable, self powered
viapm0 at pci0 dev 4 function 4
viaenv0 at viapm0: disabled
cbb0 at pci0 dev 11 function 0: Texas Instruments PCI1225 PCI-CardBus Bridge (rev. 0x01)
cbb1 at pci0 dev 11 function 1: Texas Instruments PCI1225 PCI-CardBus Bridge (rev. 0x01)
fxp0 at pci0 dev 12 function 0: i82550 Ethernet, rev 12
fxp0: interrupting at irq 11
fxp0: Ethernet address 00:02:b3:27:9a:2a
inphy0 at fxp0 phy 1: i82555 10/100 media interface, rev. 4
inphy0: 10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
emuxki0 at pci0 dev 13 function 0: Creative Labs SBLive! EMU 10000 (audio multimedia, revision 0x05)
emuxki0: interrupting at irq 5
emuxki0: TriTech TR28602 codec; no 3D stereo
audio0 at emuxki0: full duplex, mmap, independent
joy0 at pci0 dev 13 function 1: Creative Labs PCI Gameport Joystick (rev 0x05)
joy0: joystick not connected
isa0 at pcib0
pcppi0 at isa0 port 0x61
midi0 at pcppi0: PC speaker
sysbeep0 at pcppi0
isapnp0 at isa0 port 0x279: ISA Plug 'n Play device support
isapnp0: no ISA Plug 'n Play devices found
cbb0: interrupting at irq 10
cardslot0 at cbb0 slot 0 flags 0
cardbus0 at cardslot0: bus 0 device 0
pcmcia0 at cardslot0
cbb1: interrupting at irq 10
cardslot1 at cbb1 slot 1 flags 0
cardbus1 at cardslot1: bus 0 device 0
pcmcia1 at cardslot1
Kernelized RAIDframe activated
IPsec: Initialized Security Association Processing.
umass0 at uhub1 port 2 configuration 1 interface 0
umass0: TEAC TEAC FD-05PUB, rev 1.00/0.00, addr 2
umass0: using UFI over CBI
atapibus1 at umass0 channel 0: 2 targets
sd0 at atapibus1 drive 0: <TEAC, FD-05PUB, 1026> disk removable
sd0: drive offline
boot device: wd0
root on wd0a dumps on wd0b
root file system type: ffs
IP Filter: v3.4.29 initialized.  Default = pass all, Logging = enabled
wsdisplay0: screen 1 added (80x25, vt100 emulation)
wsdisplay0: screen 2 added (80x25, vt100 emulation)
wsdisplay0: screen 3 added (80x25, vt100 emulation)
wsdisplay0: screen 4 added (80x25, vt100 emulation)
Accounting started


		--Steve Bellovin, http://www.research.att.com/~smb (me)
		http://www.wilyhacker.com (2nd edition of "Firewalls" book)