[PANIC] RELENG_6: Memory modified after free

Hi,

sometimes I am gettings this panic while booting.

I had several times tried to get a core dump, but savecore(8) tells me

| savecore: unable to open bounds file, using 0


| Memory modified after free 0xc15fc000(4092) val=0 _at_ 0xc15fc000
|
|
| Fatal trap 12: page fault while in kernel mode
| cpuid = 0; apic id = 00
| fault virtual address   = 0xffff0020
| fault code              = supervisor read, page not present
| instruction pointer     = 0x20:0xc06018a7
| stack pointer           = 0x28:0xc0c20920
| frame pointer           = 0x28:0xc0c2093c
| 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         = 0 (swapper)
| panic: from debugger
| cpuid = 0
| Uptime: 1s
| Automatic reboot in 15 seconds - press a key on the console to abort
| --> Press a key on the console to reboot,
| --> or switch off the system now.

regards,

    Gordon