Relevant crash report parts.
Backtrace:
db:0:kdb.enter.default> bt
Tracing pid 11 tid 100003 td 0xfffff8000721c000
kdb_enter() at kdb_enter+0x3b/frame 0xfffffe0228ae2520
vpanic() at vpanic+0x19b/frame 0xfffffe0228ae2580
panic() at panic+0x43/frame 0xfffffe0228ae25e0
trap_pfault() at trap_pfault/frame 0xfffffe0228ae2630
trap_pfault() at trap_pfault+0x49/frame 0xfffffe0228ae2690
trap() at trap+0x29d/frame 0xfffffe0228ae27a0
calltrap() at calltrap+0x8/frame 0xfffffe0228ae27a0
--- trap 0xc, rip = 0xffffffff80cd5353, rsp = 0xfffffe0228ae2870, rbp = 0xfffffe0228ae2870 ---
runq_add() at runq_add+0x43/frame 0xfffffe0228ae2870
sched_add() at sched_add+0x150/frame 0xfffffe0228ae28b0
intr_event_schedule_thread() at intr_event_schedule_thread+0xa0/frame 0xfffffe0228ae28e0
intr_event_handle() at intr_event_handle+0xce/frame 0xfffffe0228ae2930
intr_execute_handlers() at intr_execute_handlers+0x48/frame 0xfffffe0228ae2960
lapic_handle_intr() at lapic_handle_intr+0x3e/frame 0xfffffe0228ae2980
Xapic_isr1() at Xapic_isr1+0xd3/frame 0xfffffe0228ae2980
--- interrupt, rip = 0xffffffff803f18c2, rsp = 0xfffffe0228ae2a50, rbp = 0xfffffe0228ae2a90 ---
acpi_cpu_idle() at acpi_cpu_idle+0x342/frame 0xfffffe0228ae2a90
cpu_idle_acpi() at cpu_idle_acpi+0x3f/frame 0xfffffe0228ae2ab0
cpu_idle() at cpu_idle+0x94/frame 0xfffffe0228ae2ad0
sched_idletd() at sched_idletd+0x476/frame 0xfffffe0228ae2bb0
fork_exit() at fork_exit+0x83/frame 0xfffffe0228ae2bf0
fork_trampoline() at fork_trampoline+0xe/frame 0xfffffe0228ae2bf0
--- trap 0, rip = 0, rsp = 0, rbp = 0 ---
Panic:
Fatal trap 12: page fault while in kernel mode
cpuid = 0; apic id = 00
fault virtual address = 0xffffff378335cdc8
fault code = supervisor write data, page not present
instruction pointer = 0x20:0xffffffff80cd5353
stack pointer = 0x28:0xfffffe0228ae2870
frame pointer = 0x28:0xfffffe0228ae2870
code segment = base 0x0, limit 0xfffff, type 0x1b
= DPL 0, pres 1, long 1, def32 0, gran 1
processor eflags = resume, IOPL = 0
current process = 11 (idle: cpu0)
trap number = 12
panic: page fault
cpuid = 0
KDB: enter: panic
Do all the crash reports you see look like that?
If you had a hardware issue like RAM I would expect random crashes.
Steve