uvm_fault(fffffd806c098ad0,400000000000,0,2) at uvm_fault+0x272 upageflttrap(ffff80002a45e0d0,400000000100) at upageflttrap+0xa9 sys/arch/amd64/amd64/trap.c:188 usertrap(ffff80002a45e0d0) at usertrap+0x2d8 sys/arch/amd64/amd64/trap.c:436 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x6ff3d7419020, count: -21 ddb{0}> machine ddbcpu 1 Stopped at savectx+0xae: movl $0,%gs:0x680 savectx() at savectx+0xae end of kernel end trace frame: 0x759c42248170, count: 14 ddb{1}> trace savectx() at savectx+0xae end of kernel end trace frame: 0x759c42248170, count: -1