uvm_fault(0xffffffff82e4e748, 0x7f8570a10248, 0, 2) -> e
kernel: page fault trap, code=2
Stopped at      pmap_page_remove+0x33d: xchgq   %rax,0(%r14,%rcx,1)
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*122981  25755      0     0x14000      0x200    1  reaper
pmap_page_remove(fffffd8006fe1fa0) at pmap_page_remove+0x33d _atomic_swap_64 machine/atomic.h:117 [inline]
pmap_page_remove(fffffd8006fe1fa0) at pmap_page_remove+0x33d sys/arch/amd64/amd64/pmap.c:1990
uvm_anfree_list(fffffd807a99d6a8,0) at uvm_anfree_list+0x98
amap_wipeout(fffffd80619c00b0) at amap_wipeout+0x1af sys/uvm/uvm_amap.c:502
uvm_unmap_detach(ffff80002a155450,1) at uvm_unmap_detach+0x7d sys/uvm/uvm_map.c:1354
uvm_map_teardown(fffffd80686f0540) at uvm_map_teardown+0x2f8 sys/uvm/uvm_map.c:2554
uvmspace_free(fffffd80686f0540) at uvmspace_free+0xa6 sys/uvm/uvm_map.c:3461
reaper(ffff80002a149718) at reaper+0x197 sys/kern/kern_exit.c:463
end trace frame: 0x0, count: 8
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