Re: kernel trap 12 with interrupts disabled

On  9 Nov, I wrote:
> I just got one of these shortly after I rebooted my November 7th
> -CURRENT box. DDB doesn't show much interesting.
> 
>  kernel trap 12 with interrupts disabled
> 
> 
> Fatal trap 12: page fault while in kernel mode
> cpuid = 0; apic id = 00
> fault virtual address   = 0xbc04d753
> fault code              = supervisor read, page not present
> instruction pointer     = 0x8:0xc0685ddf
> stack pointer           = 0x10:0xe5f3bca8
> frame pointer           = 0x10:0xe5f3bcfc
> code segment            = base 0x0, limit 0xfffff, type 0x1b
>                         = DPL 0, pres 1, def32 1, gran 1
> processor eflags        = resume, IOPL = 0
> current process         = 519 (setiathome)
> kernel: type 12 trap, code=0
> Stopped at      mi_switch+0xcf: cmpl    0x8(%esi),%ebx
> db> tr
> mi_switch(c6bbc500,df,c08a3da3,f8,0) at mi_switch+0xcf
> ast(e5f3bd48) at ast+0x3f2
> doreti_ast() at doreti_ast+0x17
> 
> Alas, I didn't have enough free space to capture a core file B-(

This problem doesn't appear to be reproduceable and doesn't seem to be
load dependent.  I had portupgrade cranking for many hours yesterday
without a hiccup.  I cleaned up a bunch of old distfiles and packages,
so I should have sufficient space to get a core dump in case this
problem happens again.

I forgot to include the vital statistics.  BTW, the RAM is ECC.

Copyright (c) 1992-2003 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 5.1-CURRENT #35: Fri Nov  7 14:50:18 PST 2003
    dl_at_scratch.catspoiler.org:/usr/obj/usr/src/sys/GENERICSMB
Preloaded elf kernel "/boot/kernel/kernel" at 0xc0a9e000.
Preloaded elf module "/boot/kernel/aout.ko" at 0xc0a9e244.
ACPI APIC Table: <GBT    AWRDACPI>
Timecounter "i8254" frequency 1193182 Hz quality 0
CPU: AMD Athlon(tm) XP 1900+ (1608.23-MHz 686-class CPU)
  Origin = "AuthenticAMD"  Id = 0x662  Stepping = 2
  Features=0x383fbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,MMX,FXSR,SSE>
  AMD Features=0xc0480000<MP,AMIE,DSP,3DNow!>
real memory  = 1073676288 (1023 MB)
avail memory = 1033592832 (985 MB)
ioapic0 <Version 1.1> irqs 0-23 on motherboard
Pentium Pro MTRR support enabled
acpi0: <GBT    AWRDACPI> on motherboard
pcibios: BIOS version 2.10
Using $PIR table, 11 entries at 0xc00fdc30
acpi0: Power Button (fixed)
Timecounter "ACPI-fast" frequency 3579545 Hz quality 1000
acpi_timer0: <24-bit timer at 3.579545MHz> port 0x4008-0x400b on acpi0
acpi_cpu0: <CPU> on acpi0
acpi_button0: <Power Button> on acpi0
acpi_button1: <Sleep Button> on acpi0
pcib0: <ACPI Host-PCI bridge> port 0x6000-0x607f,0x5000-0x500f,0x4080-0x40ff,0x4000-0x407f,0xcf8-0xcff on acpi0
pci0: <ACPI PCI bus> on pcib0
pcib0: slot 7 INTD is routed to irq 10
pcib0: slot 7 INTD is routed to irq 10
agp0: <AMD 761 host to AGP bridge> port 0xc000-0xc003 mem 0xef020000-0xef020fff,0xe8000000-0xebffffff at device 0.0 on pci0
pcib1: <PCIBIOS PCI-PCI bridge> at device 1.0 on pci0
pci1: <PCI bus> on pcib1
pci_cfgintr: 1:5 INTA BIOS irq 15
pci1: <display, VGA> at device 5.0 (no driver attached)
isab0: <PCI-ISA bridge> at device 7.0 on pci0
isa0: <ISA bus> on isab0
atapci0: <VIA 82C686B UDMA100 controller> port 0xc400-0xc40f at device 7.1 on pci0
ata0: at 0x1f0 irq 14 on atapci0
ata0: [MPSAFE]
ata1: at 0x170 irq 15 on atapci0
ata1: [MPSAFE]
uhci0: <VIA 83C572 USB controller> port 0xc800-0xc81f irq 10 at device 7.2 on pci0
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
uhub0: port error, restarting port 1
uhub0: port error, giving up port 1
uhub0: port error, restarting port 2
uhub0: port error, giving up port 2
uhci1: <VIA 83C572 USB controller> port 0xcc00-0xcc1f irq 10 at device 7.3 on pci0
usb1: <VIA 83C572 USB controller> on uhci1
usb1: USB revision 1.0
uhub1: VIA UHCI root hub, class 9/0, rev 1.00/1.00, addr 1
uhub1: 2 ports with 2 removable, self powered
uhub1: port error, restarting port 1
uhub1: port error, giving up port 1
uhub1: port error, restarting port 2
uhub1: port error, giving up port 2
viapropm0: SMBus I/O base at 0x5000
viapropm0: <VIA VT82C686A Power Management Unit> port 0x5000-0x500f at device 7.4 on pci0
viapropm0: SMBus revision code 0x40
smbus0: <System Management Bus> on viapropm0
smb0: <SMBus generic I/O> on smbus0
fxp0: <Intel 82550 Pro/100 Ethernet> port 0xe000-0xe03f mem 0xef000000-0xef01ffff,0xef021000-0xef021fff irq 18 at device 10.0 on pci0
fxp0: Ethernet address 00:02:b3:5c:8c:e0
miibus0: <MII bus> on fxp0
inphy0: <i82555 10/100 media interface> on miibus0
inphy0:  10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
ahc0: <Adaptec 19160B Ultra160 SCSI adapter> port 0xe400-0xe4ff mem 0xef022000-0xef022fff irq 16 at device 12.0 on pci0
aic7892: Ultra160 Wide Channel A, SCSI Id=7, 32/253 SCBs
fdc0: <Enhanced floppy controller (i82077, NE72065 or clone)> port 0x3f7,0x3f0-0x3f5 irq 6 drq 2 on acpi0
fdc0: FIFO enabled, 8 bytes threshold
fd0: <1440-KB 3.5" drive> on fdc0 drive 0
sio0 port 0x3f8-0x3ff irq 4 on acpi0
sio0: type 16550A, console
sio1 port 0x2f8-0x2ff irq 3 on acpi0
sio1: type 16550A
ppc0 port 0x778-0x77b,0x378-0x37f irq 7 drq 3 on acpi0
ppc0: SMC-like chipset (ECP/EPP/PS2/NIBBLE) in COMPATIBLE mode
ppc0: FIFO with 16/16/8 bytes threshold
ppbus0: <Parallel port bus> on ppc0
plip0: <PLIP network interface> on ppbus0
lpt0: <Printer> on ppbus0
lpt0: Interrupt-driven port
ppi0: <Parallel I/O> on ppbus0
atkbdc0: <Keyboard controller (i8042)> port 0x64,0x60 irq 1 on acpi0
atkbd0: <AT Keyboard> flags 0x1 irq 1 on atkbdc0
kbd0 at atkbd0
psm0: <PS/2 Mouse> irq 12 on atkbdc0
psm0: model IntelliMouse Explorer, device ID 4
npx0: [FAST]
npx0: <math processor> on motherboard
npx0: INT 16 interface
orm0: <Option ROM> at iomem 0xc0000-0xcc7ff on isa0
pmtimer0 on isa0
sc0: <System console> at flags 0x100 on isa0
sc0: VGA <16 virtual consoles, flags=0x100>
vga0: <Generic ISA VGA> at port 0x3c0-0x3df iomem 0xa0000-0xbffff on isa0
Timecounter "TSC" frequency 1608225604 Hz quality 800
Timecounters tick every 10.000 msec
Waiting 3 seconds for SCSI devices to settle
acpi_cpu: throttling enabled, 2 steps (100% to 50.0%), currently 100.0%
GEOM: create disk cd0 dp=0xc690ce00
GEOM: create disk da0 dp=0xc699e450
da0 at ahc0 bus 0 target 0 lun 0
da0: <SEAGATE ST336706LW 010A> Fixed Direct Access SCSI-3 device 
da0: 160.000MB/s transfers (80.000MHz, offset 63, 16bit), Tagged Queueing Enabled
da0: 35003MB (71687370 512 byte sectors: 255H 63S/T 4462C)
cd0 at ahc0 bus 0 target 6 lun 0
cd0: <NEC CD-ROM DRIVE:462 1.14> Removable CD-ROM SCSI-2 device 
cd0: 10.000MB/s transfers (10.000MHz, offset 15)
cd0: Attempt to query device size failed: NOT READY, Medium not present
Mounting root from ufs:/dev/da0s1a
WARNING: / was not properly dismounted