Hello, Can anyone help me try and work out what went wrong here? I am running on 7.0-PRERELEASE on amd64. However, the file kern_event.c hasn't changed anytime since then in 7-STABLE. Fatal trap 12: page fault while in kernel mode cpuid = 2; apic id = 02 fault virtual address = 0x9a050 fault code = supervisor write data, page not present instruction pointer = 0x8:0xffffffff8027f877 stack pointer = 0x10:0xffffffffb4c0a9e0 frame pointer = 0x10:0xffffff005c0ccda0 code segment = base 0x0, limit 0xfffff, type 0x1b = DPL 0, pres 1, long 1, def32 0, gran 1 processor eflags = interrupt enabled, resume, IOPL = 0 current process = 12949 (smtpd) trap number = 12 panic: page fault cpuid = 2 Uptime: 6d11h8m19s Physical memory: 8183 MB (kgdb) bt #0 doadump () at pcpu.h:194 #1 0x0000000000000004 in ?? () #2 0xffffffff8029e6ef in boot (howto=260) at /usr/src/sys/kern/kern_shutdown.c:409 #3 0xffffffff8029eb37 in panic (fmt=Variable "fmt" is not available. ) at /usr/src/sys/kern/kern_shutdown.c:563 #4 0xffffffff803df54e in trap_fatal (frame=0xc, eva=Variable "eva" is not available. ) at /usr/src/sys/amd64/amd64/trap.c:724 #5 0xffffffff803df903 in trap_pfault (frame=0xffffffffb4c0a930, usermode=0) at /usr/src/sys/amd64/amd64/trap.c:641 #6 0xffffffff803e00a1 in trap (frame=0xffffffffb4c0a930) at /usr/src/sys/amd64/amd64/trap.c:410 #7 0xffffffff803c6fde in calltrap () at /usr/src/sys/amd64/amd64/exception.S:169 #8 0xffffffff8027f877 in kqueue_close (fp=0xffffff0114352000, td=0xffffff003bcb3680) at /usr/src/sys/kern/kern_event.c:1457 #9 0xffffffff802762cf in fdrop (fp=0xffffff0114352000, td=0xffffff003bcb3680) at file.h:297 #10 0xffffffff802775cd in closef (fp=0xffffff0114352000, td=0xffffff003bcb3680) at /usr/src/sys/kern/kern_descrip.c:1958 #11 0xffffffff80277d3e in kern_close (td=0xffffff003bcb3680, fd=Variable "fd" is not available. ) at /usr/src/sys/kern/kern_descrip.c:1054 #12 0xffffffff803dfaeb in syscall (frame=0xffffffffb4c0ac70) at /usr/src/sys/amd64/amd64/trap.c:852 #13 0xffffffff803c71eb in Xfast_syscall () at /usr/src/sys/amd64/amd64/exception.S:290 #14 0x0000000800bee16c in ?? () Previous frame inner to this frame (corrupt stack?) The offending line: #8 0xffffffff8027f877 in kqueue_close (fp=0xffffff0114352000, td=0xffffff003bcb3680) at /usr/src/sys/kern/kern_event.c:1457 1457 while ((kn = SLIST_FIRST(&kq->kq_knlist[i])) != NULL) { The process that made the syscall was a postfix smtpd inside a jail. It had been running fine for almost a week before this. Any hints appreciated, - Andrew