Kernel panic and general question on stability for FreeBSD 8 xen domU

[Fred Crandall]

Hi there all,

I have a paravirtualized  FreeBSD 8 xen domU going that I have
intermittent and repeatable kernel panic issues with. This is using a
i386 xen paravirtualized kernel from up to date (as of this morning at
the latest try) RELENG_8 sources. Ive tried this on a linux 64bit dom0
and 32bit dom0 both running xen 3.4.2.  The kernel will panic at
random from anywhere form a few hours to a few days with:

panic: mutex vm page queue mutex not owned at
/usr/src/sys/i386/xen/xen_machdep.c:431
KDB: enter: panic

Fairly low load when this happens, currently the domU machine only
runs some minor sendmail load. I can also get the domU virtual to
kernel panic in the same way on demand by having the configure script
run on the libgcrypt port or by running and exiting memtest. The
libgcrypt issue being the same as described in PR 140313.

Also tried running the domU kernel without SMP support, I see the same results.

So curious if anyone has any ideas on something Im missing or if
others see similar issues on a RELENG_8 i386 xen kernel.

Below, is also my current kernel configuration.

cpu		I686_CPU
ident		XEN

makeoptions	DEBUG=-g		# Build kernel with gdb(1) debug symbols
makeoptions	MODULES_OVERRIDE=""

options 	SCHED_ULE		# ULE scheduler
options 	PREEMPTION		# Enable kernel thread preemption
#options 	SCHED_4BSD		

options 	INET			# InterNETworking
options 	INET6			# IPv6 communications protocols
options 	SCTP			# Stream Control Transmission Protocol
options 	FFS			# Berkeley Fast Filesystem
options 	SOFTUPDATES		# Enable FFS soft updates support
options 	UFS_ACL			# Support for access control lists
options 	UFS_DIRHASH		# Improve performance on big directories
options 	UFS_GJOURNAL		# Enable gjournal-based UFS journaling
options 	NFSCLIENT		# Network Filesystem Client
options 	NFSSERVER		# Network Filesystem Server
options 	NFSLOCKD		# Network Lock Manager
options 	NFS_ROOT		# NFS usable as /, requires NFSCLIENT
options 	MSDOSFS			# MSDOS Filesystem
options 	CD9660			# ISO 9660 Filesystem
options 	PROCFS			# Process filesystem (requires PSEUDOFS)
options 	PSEUDOFS		# Pseudo-filesystem framework
options 	GEOM_PART_GPT		# GUID Partition Tables.
options 	GEOM_LABEL		# Provides labelization
options 	COMPAT_43TTY		# BSD 4.3 TTY compat (sgtty)
options 	COMPAT_FREEBSD4		# Compatible with FreeBSD4
options 	COMPAT_FREEBSD5		# Compatible with FreeBSD5
options 	COMPAT_FREEBSD6		# Compatible with FreeBSD6
options 	COMPAT_FREEBSD7		# Compatible with FreeBSD7
options 	KTRACE			# ktrace(1) support
options 	STACK			# stack(9) support
options 	SYSVSHM			# SYSV-style shared memory
options 	SYSVMSG			# SYSV-style message queues
options 	SYSVSEM			# SYSV-style semaphores
options 	_KPOSIX_PRIORITY_SCHEDULING # POSIX P1003_1B real-time extensions
options 	KBD_INSTALL_CDEV	# install a CDEV entry in /dev
options 	AUDIT			# Security event auditing

# Debugging for use in -current
options 	KDB			# Enable kernel debugger support.
options 	DDB			# Support DDB.
options 	GDB			# Support remote GDB.
options 	INVARIANTS		# Enable calls of extra sanity checking
options 	INVARIANT_SUPPORT	# Extra sanity checks of internal
structures, required by INVARIANTS
options 	WITNESS			# Enable checks to detect deadlocks and cycles
options 	WITNESS_SKIPSPIN	# Don't run witness on spinlocks for speed

options 	PAE
nooption	NATIVE
option		XEN
nodevice	atpic
nodevice	isa
options 	MCLSHIFT=12

options         IPFIREWALL
# To make an SMP kernel, the next two lines are needed
#options 	SMP			# Symmetric MultiProcessor Kernel
#device		apic			# I/O APIC


device		atkbdc		# AT keyboard controller
device		atkbd		# AT keyboard
device		psm		# PS/2 mouse
device		pci

device		kbdmux		# keyboard multiplexer

# Pseudo devices.
device		loop		# Network loopback
device		random		# Entropy device
device		ether		# Ethernet support
device		tun		# Packet tunnel.
device		pty		# Pseudo-ttys (telnet etc)
device		md		# Memory "disks"
device		gif		# IPv6 and IPv4 tunneling
device		faith		# IPv6-to-IPv4 relaying (translation)

# The `bpf' device enables the Berkeley Packet Filter.
# Be aware of the administrative consequences of enabling this!
# Note that 'bpf' is required for DHCP.
device		bpf		# Berkeley packet filter


The domU kernel is booted via pvgrub, ther kernel called via:

kernel /boot/kernel/kernel
vfs.root.mountfrom=ufs:xbd0s1a,kern.hz=100,xencons=tty


Thanks all,

Fred