5.1-RELEASE-p2 panic

For the last couple weeks, I have been getting a daily panic just before
24 hours uptime.  

Seems to have started after -p2 patches and rebuild.  The system was
solid up until that point.  I know I have seen others complain about
this "24 hr panic" but no suggestions.

[.....]
panic: from debugger
panic messages:
---
Fatal trap 12: page fault while in kernel mode
fault virtual address   = 0xcf41224
fault code              = supervisor read, page not present
instruction pointer     = 0x8:0xc0380a07
stack pointer           = 0x10:0xde0f7b28
frame pointer           = 0x10:0xde0f7b80
code segment            = base 0x0, limit 0xfffff, type 0x1b
                        = DPL 0, pres 1, def32 1, gran 1
processor eflags        = interrupt enabled, resume, IOPL = 0
current process         = 51776 (sudo)
panic: from debugger


Fatal trap 3: breakpoint instruction fault while in kernel mode
instruction pointer     = 0x8:0xc047eb54
stack pointer           = 0x10:0xde0f78a8
frame pointer           = 0x10:0xde0f78b4
code segment            = base 0x0, limit 0xfffff, type 0x1b
                        = DPL 0, pres 1, def32 1, gran 1
processor eflags        = IOPL = 0
current process         = 51776 (sudo)
panic: from debugger            
Uptime: 23h52m33s               
Dumping 511 MB                  
                                
#0  doadump () at /usr/src/sys/kern/kern_shutdown.c:238
238             dumping++;      
(kgdb) bt                       
#0  doadump () at /usr/src/sys/kern/kern_shutdown.c:238
#1  0xc0309828 in boot (howto=260) at
/usr/src/sys/kern/kern_shutdown.c:370
#2  0xc0309b1b in panic () at /usr/src/sys/kern/kern_shutdown.c:543
#3  0xc0162bb2 in db_panic () at /usr/src/sys/ddb/db_command.c:448
#4  0xc0162b32 in db_command (last_cmdp=0xc0518d40, cmd_table=0x0,
    aux_cmd_tablep=0xc050fbbc, aux_cmd_tablep_end=0xc050fbd4)
    at /usr/src/sys/ddb/db_command.c:346
#5  0xc0162c46 in db_command_loop () at
/usr/src/sys/ddb/db_command.c:470
#6  0xc01659da in db_trap (type=12, code=0) at
/usr/src/sys/ddb/db_trap.c:72
#7  0xc047e8b5 in kdb_trap (type=12, code=0, regs=0xde0f7ae8)
    at /usr/src/sys/i386/i386/db_interface.c:170
#8  0xc04905c2 in trap_fatal (frame=0xde0f7ae8, eva=0)
    at /usr/src/sys/i386/i386/trap.c:829
#9  0xc04902d2 in trap_pfault (frame=0xde0f7ae8, usermode=0,
eva=217322020)
    at /usr/src/sys/i386/i386/trap.c:748
#10 0xc048fead in trap (frame=  
      {tf_fs = -569442280, tf_es = 16, tf_ds = -962985968, tf_edi = 152,
tf_esi
= 0, tf_ebp = -569410688, tf_isp = -569410796, tf_ebx = -964577280,
tf_edx = -96
2953984, tf_ecx = -569410664, tf_eax = 217321984, tf_trapno = 12, tf_err
= 0, tf
_eip = -1070069241, tf_cs = 8, tf_eflags = 66182, tf_esp = 12, tf_ss =
-56941074
8}) at /usr/src/sys/i386/i386/trap.c:433
#11 0xc0480208 in calltrap () at {standard input}:96
#12 0xc0380b91 in sysctl_rtsock (oidp=0xc054db40, arg1=0xde0f7cb0,
arg2=4,
---Type <return> to continue, or q <return> to quit---
    req=0x0) at /usr/src/sys/net/rtsock.c:1048
#13 0xc03121ba in sysctl_root (oidp=0x0, arg1=0x98, arg2=0,
req=0xc681b800)
    at /usr/src/sys/kern/kern_sysctl.c:1173
#14 0xc031245d in userland_sysctl (td=0x0, name=0xde0f7ca8, namelen=6,
    old=0x0, oldlenp=0xc681b800, inkernel=0, new=0x98, newlen=0,
    retval=0xde0f7ca4) at /usr/src/sys/kern/kern_sysctl.c:1280
#15 0xc03122a0 in __sysctl (td=0x0, uap=0xde0f7d10)
    at /usr/src/sys/kern/kern_sysctl.c:1210
#16 0xc04908be in syscall (frame=
      {tf_fs = -1078001617, tf_es = 47, tf_ds = -1078001617, tf_edi = 0,
tf_esi
= -1077937156, tf_ebp = -1077937288, tf_isp = -569410188, tf_ebx =
672630356, tf
_edx = 0, tf_ecx = -1077937152, tf_eax = 202, tf_trapno = 12, tf_err =
2, tf_eip
 = 672127299, tf_cs = 31, tf_eflags = 663, tf_esp = -1077937332, tf_ss =
47})
    at /usr/src/sys/i386/i386/trap.c:1021
#17 0xc048025d in Xint0x80_syscall () at {standard input}:138
---Can't read userspace from dump, or kernel process---