Bug 123689

If a USB device is inserted into my system after it has booted up, the kernel panics.  USB devices that are inserted before bootup do not cause a panic.  This ONLY occurs if usb is loaded via a kernel module (in my case from loader.conf).  If I had devices ehci, uhci, and usb to my kernel config then the problem goes away.

The panic screen:

Fatal trap 12: page fault while in kernel mode
cpuid = 0; apic id = 00
fault virtual address    = 0x290
fault code               = supervisor read data, page not present
instruction pointer      = 0x8:0xffffffff8061b1e5
stack pointer            = 0x10:0xffffffffaad95dd0
frame pointer            = 0x10:0xffffffffaad95e10
code segment             = base rx0, limit 0xfffff, type 0x1b
                         = DPL 0, pres 1, long 1, def32 0, gran 1
processor eflags         = interrupt enabled, resume, IOPL = 0
current process          = 31 (usb3)
trap number              = 12
panic: page fault

I have tried to get something that can be debugged, but when this crash occurs no dump gets written.  The system completely hangs at this point and requires a hard reset.

If I enable KDB/DDB in the kernel then the problem goes away!

I am not sure how to debug this further - open to suggestions.

My kernel config:

ident		IGOR
maxusers	256
makeoptions	DEBUG=-g


####################################################################
# SCHEDULER OPTIONS

options 	SCHED_ULE		#ULE scheduler


#####################################################################
# COMPATIBILITY OPTIONS

options		COMPAT_43TTY
options		COMPAT_IA32
options 	COMPAT_FREEBSD4		#Compatible with FreeBSD4
options		COMPAT_FREEBSD5
options		COMPAT_FREEBSD6
options 	SYSVSHM			#SYSV-style shared memory
options 	SYSVMSG			#SYSV-style message queues
options 	SYSVSEM			#SYSV-style semaphores


#####################################################################
# CPU OPTIONS

cpu		HAMMER
device		acpi
options		SMP
options		PREEMPTION
options		ADAPTIVE_GIANT
options		STOP_NMI


#####################################################################
# NETWORKING OPTIONS

options 	INET			#InterNETworking
device		loop		# Network loopback
device		ether		# Ethernet support
device		bpf		# Berkeley packet filter


#####################################################################
# FILESYSTEM OPTIONS

options 	FFS			#Berkeley Fast Filesystem
options 	SOFTUPDATES		#Enable FFS soft updates support
options 	UFS_DIRHASH		#Improve performance on big directories
options		UFS_GJOURNAL
device		random		# Entropy device


#####################################################################
# MISCELLANEOUS DEVICES AND OPTIONS

device		pty		# Pseudo-ttys (telnet etc)


#####################################################################
# HARDWARE BUS CONFIGURATION

device		pci


#####################################################################
# HARDWARE DEVICE CONFIGURATION

device		atkbdc		# AT keyboard controller
device		atkbd		# AT keyboard
options		KBD_INSTALL_CDEV
device		kbdmux
device		psm
device		vga		# VGA video card driver
device		sc
options		SC_HISTORY_SIZE=1000
device		ata
device		atadisk			# ATA disk drives
device		atapicd			# ATAPI CDROM drives
options 	ATA_STATIC_ID		#Static device numbering

options 	_KPOSIX_PRIORITY_SCHEDULING #Posix P1003_1B real-time extensions
options		CONSPEED=115200

#device		uhci
#device		ehci
#device		usb


dmesg:

Copyright (c) 1992-2008 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 is a registered trademark of The FreeBSD Foundation.
FreeBSD 7.0-STABLE #4: Thu May 15 00:09:56 SAST 2008
    root@igor.geek.sh:/usr/obj/usr/src/sys/IGOR
Timecounter "i8254" frequency 1193182 Hz quality 0
CPU: Intel(R) Core(TM)2 Duo CPU     E8500  @ 3.16GHz (3185.32-MHz K8-class CPU)
  Origin = "GenuineIntel"  Id = 0x10676  Stepping = 6
  Features=0xbfebfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CLFLUSH,DTS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE>
  Features2=0x8e3fd<SSE3,RSVD2,MON,DS_CPL,VMX,SMX,EST,TM2,SSSE3,CX16,xTPR,PDCM,<b19>>
  AMD Features=0x20100800<SYSCALL,NX,LM>
  AMD Features2=0x1<LAHF>
  Cores per package: 2
usable memory = 8509706240 (8115 MB)
avail memory  = 8224993280 (7843 MB)
ACPI APIC Table: <INTEL  DG33BU  >
FreeBSD/SMP: Multiprocessor System Detected: 2 CPUs
 cpu0 (BSP): APIC ID:  0
 cpu1 (AP): APIC ID:  1
ioapic0: Changing APIC ID to 2
ioapic0 <Version 2.0> irqs 0-23 on motherboard
kbd1 at kbdmux0
acpi0: <INTEL DG33BU> on motherboard
acpi0: [ITHREAD]
acpi0: Power Button (fixed)
Timecounter "ACPI-fast" frequency 3579545 Hz quality 1000
acpi_timer0: <24-bit timer at 3.579545MHz> port 0x408-0x40b on acpi0
acpi_hpet0: <High Precision Event Timer> iomem 0xfed00000-0xfed003ff on acpi0
Timecounter "HPET" frequency 14318180 Hz quality 900
cpu0: <ACPI CPU> on acpi0
est0: <Enhanced SpeedStep Frequency Control> on cpu0
est0: Setting 3163 MHz
p4tcc0: <CPU Frequency Thermal Control> on cpu0
cpu1: <ACPI CPU> on acpi0
est1: <Enhanced SpeedStep Frequency Control> on cpu1
est1: Setting 3163 MHz
p4tcc1: <CPU Frequency Thermal Control> on cpu1
acpi_button0: <Sleep Button> on acpi0
pcib0: <ACPI Host-PCI bridge> port 0xcf8-0xcff on acpi0
pci0: <ACPI PCI bus> on pcib0
pcib1: <ACPI PCI-PCI bridge> at device 1.0 on pci0
pci1: <ACPI PCI bus> on pcib1
vgapci0: <VGA-compatible display> port 0x3000-0x30ff mem 0xd0000000-0xdfffffff,0xe0200000-0xe020ffff irq 16 at device 0.0 on pci1
pci1: <multimedia> at device 0.1 (no driver attached)
pci0: <simple comms> at device 3.0 (no driver attached)
em0: <Intel(R) PRO/1000 Network Connection Version - 6.7.3> port 0x4400-0x441f mem 0xe0300000-0xe031ffff,0xe0324000-0xe0324fff irq 20 at device 25.0 on pci0
em0: Using MSI interrupt
em0: Ethernet address: 00:1c:c0:30:9b:91
em0: [FILTER]
uhci0: <UHCI (generic) USB controller> port 0x40e0-0x40ff irq 18 at device 26.0 on pci0
uhci0: [GIANT-LOCKED]
uhci0: [ITHREAD]
usb0: <UHCI (generic) USB controller> on uhci0
usb0: USB revision 1.0
uhub0: <Intel UHCI root hub, class 9/0, rev 1.00/1.00, addr 1> on usb0
uhub0: 2 ports with 2 removable, self powered
uhci1: <UHCI (generic) USB controller> port 0x40c0-0x40df irq 21 at device 26.1 on pci0
uhci1: [GIANT-LOCKED]
uhci1: [ITHREAD]
usb1: <UHCI (generic) USB controller> on uhci1
usb1: USB revision 1.0
uhub1: <Intel UHCI root hub, class 9/0, rev 1.00/1.00, addr 1> on usb1
uhub1: 2 ports with 2 removable, self powered
uhci2: <UHCI (generic) USB controller> port 0x40a0-0x40bf irq 17 at device 26.2 on pci0
uhci2: [GIANT-LOCKED]
uhci2: [ITHREAD]
usb2: <UHCI (generic) USB controller> on uhci2
usb2: USB revision 1.0
uhub2: <Intel UHCI root hub, class 9/0, rev 1.00/1.00, addr 1> on usb2
uhub2: 2 ports with 2 removable, self powered
ehci0: <EHCI (generic) USB 2.0 controller> mem 0xe0325c00-0xe0325fff irq 17 at device 26.7 on pci0
ehci0: [GIANT-LOCKED]
ehci0: [ITHREAD]
usb3: EHCI version 1.0
usb3: companion controllers, 2 ports each: usb0 usb1 usb2
usb3: <EHCI (generic) USB 2.0 controller> on ehci0
usb3: USB revision 2.0
uhub3: <Intel EHCI root hub, class 9/0, rev 2.00/1.00, addr 1> on usb3
uhub3: 6 ports with 6 removable, self powered
pci0: <multimedia> at device 27.0 (no driver attached)
pcib2: <ACPI PCI-PCI bridge> at device 28.0 on pci0
pci2: <ACPI PCI bus> on pcib2
pcib3: <ACPI PCI-PCI bridge> at device 28.1 on pci0
pci3: <ACPI PCI bus> on pcib3
atapci0: <Marvell 88SX6101 UDMA133 controller> port 0x2018-0x201f,0x2024-0x2027,0x2010-0x2017,0x2020-0x2023,0x2000-0x200f mem 0xe0100000-0xe01001ff irq 17 at device 0.0 on pci3
atapci0: [ITHREAD]
ata2: <ATA channel 0> on atapci0
ata2: [ITHREAD]
pcib4: <ACPI PCI-PCI bridge> at device 28.2 on pci0
pci4: <ACPI PCI bus> on pcib4
pcib5: <ACPI PCI-PCI bridge> at device 28.3 on pci0
pci5: <ACPI PCI bus> on pcib5
pcib6: <ACPI PCI-PCI bridge> at device 28.4 on pci0
pci6: <ACPI PCI bus> on pcib6
uhci3: <UHCI (generic) USB controller> port 0x4080-0x409f irq 23 at device 29.0 on pci0
uhci3: [GIANT-LOCKED]
uhci3: [ITHREAD]
usb4: <UHCI (generic) USB controller> on uhci3
usb4: USB revision 1.0
uhub4: <Intel UHCI root hub, class 9/0, rev 1.00/1.00, addr 1> on usb4
uhub4: 2 ports with 2 removable, self powered
uhci4: <UHCI (generic) USB controller> port 0x4060-0x407f irq 19 at device 29.1 on pci0
uhci4: [GIANT-LOCKED]
uhci4: [ITHREAD]
usb5: <UHCI (generic) USB controller> on uhci4
usb5: USB revision 1.0
uhub5: <Intel UHCI root hub, class 9/0, rev 1.00/1.00, addr 1> on usb5
uhub5: 2 ports with 2 removable, self powered
uhci5: <UHCI (generic) USB controller> port 0x4040-0x405f irq 18 at device 29.2 on pci0
uhci5: [GIANT-LOCKED]
uhci5: [ITHREAD]
usb6: <UHCI (generic) USB controller> on uhci5
usb6: USB revision 1.0
uhub6: <Intel UHCI root hub, class 9/0, rev 1.00/1.00, addr 1> on usb6
uhub6: 2 ports with 2 removable, self powered
ehci1: <EHCI (generic) USB 2.0 controller> mem 0xe0325800-0xe0325bff irq 23 at device 29.7 on pci0
ehci1: [GIANT-LOCKED]
ehci1: [ITHREAD]
usb7: EHCI version 1.0
usb7: companion controllers, 2 ports each: usb4 usb5 usb6
usb7: <EHCI (generic) USB 2.0 controller> on ehci1
usb7: USB revision 2.0
uhub7: <Intel EHCI root hub, class 9/0, rev 2.00/1.00, addr 1> on usb7
uhub7: 6 ports with 6 removable, self powered
pcib7: <ACPI PCI-PCI bridge> at device 30.0 on pci0
pci7: <ACPI PCI bus> on pcib7
pci7: <network, ethernet> at device 1.0 (no driver attached)
pci7: <serial bus, FireWire> at device 3.0 (no driver attached)
isab0: <PCI-ISA bridge> at device 31.0 on pci0
isa0: <ISA bus> on isab0
atapci1: <Intel AHCI controller> port 0x4428-0x442f,0x4434-0x4437,0x4420-0x4427,0x4430-0x4433,0x4020-0x403f mem 0xe0325000-0xe03257ff irq 21 at device 31.2 on pci0
atapci1: [ITHREAD]
atapci1: AHCI Version 01.20 controller with 6 ports detected
ata3: <ATA channel 0> on atapci1
ata3: [ITHREAD]
ata4: <ATA channel 1> on atapci1
ata4: [ITHREAD]
ata5: <ATA channel 2> on atapci1
ata5: [ITHREAD]
ata6: <ATA channel 3> on atapci1
ata6: [ITHREAD]
ata7: <ATA channel 4> on atapci1
ata7: [ITHREAD]
ata8: <ATA channel 5> on atapci1
ata8: [ITHREAD]
pci0: <serial bus, SMBus> at device 31.3 (no driver attached)
orm0: <ISA Option ROM> at iomem 0xd2800-0xd3fff on isa0
atkbdc0: <Keyboard controller (i8042)> at port 0x60,0x64 on isa0
atkbd0: <AT Keyboard> irq 1 on atkbdc0
kbd0 at atkbd0
atkbd0: [GIANT-LOCKED]
atkbd0: [ITHREAD]
sc0: <System console> at flags 0x100 on isa0
sc0: VGA <16 virtual consoles, flags=0x300>
vga0: <Generic ISA VGA> at port 0x3c0-0x3df iomem 0xa0000-0xbffff on isa0
ukbd0: <Logitech USB Multimedia Keyboard, class 0/0, rev 1.10/0.70, addr 2> on uhub0
kbd2 at ukbd0
ums0: <Microsoft SideWinder? Mouse, class 0/0, rev 2.00/2.25, addr 2> on uhub2
ums0: 5 buttons and Z dir.
ugen0: <vendor 0x0aa8 product 0x8001, class 0/0, rev 1.10/2.02, addr 2> on uhub6
Timecounters tick every 1.000 msec
acd0: DMA limited to UDMA33, device found non-ATA66 cable
acd0: DVDR <LITE-ON DVDRW SOHW-1653S/CS0T> at ata2-master UDMA33
ad6: 715404MB <Seagate ST3750330AS SD15> at ata3-master SATA300
ad8: 715404MB <Seagate ST3750330AS SD15> at ata4-master SATA300
SMP: AP CPU #1 Launched!
GEOM_MIRROR: Device mirror/gm0 launched (1/2).
GEOM_MIRROR: Device gm0: rebuilding provider ad6s2.
Trying to mount root from ufs:/dev/mirror/gm0a

How-To-Repeat: Load usb drivers as kernel module, boot up, insert usb device.