uvm_fault(0xfffffd807362d560, 0x4, 0, 1) -> e
kernel: page fault trap, code=0
Stopped at      igmp_leavegroup+0x80:   movl    0x4(%rax),%r12d
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
igmp_leavegroup(ffff800000d04d00) at igmp_leavegroup+0x80 sys/netinet/igmp.c:521
in_delmulti(ffff800000d04d00) at in_delmulti+0xb7 sys/netinet/in.c:920
ip_freemoptions(ffff800000c1e730) at ip_freemoptions+0x4d sys/netinet/ip_output.c:1764
in_pcbdetach(fffffd80671ccbf0) at in_pcbdetach+0xf3 sys/netinet/in_pcb.c:584
udp_detach(fffffd806ee6b008) at udp_detach+0x3b sys/netinet/udp_usrreq.c:1249
soclose(fffffd806ee6b008,0) at soclose+0x245 sys/kern/uipc_socket.c:351
soo_close(fffffd8068f98900,ffff8000230e1cf0) at soo_close+0x40
fdrop(fffffd8068f98900,ffff8000230e1cf0) at fdrop+0xc7 sys/kern/kern_descrip.c:1279
closef(fffffd8068f98900,ffff8000230e1cf0) at closef+0x117 sys/kern/kern_descrip.c:1263
fdfree(ffff8000230e1cf0) at fdfree+0xf3 sys/kern/kern_descrip.c:1195
exit1(ffff8000230e1cf0,0,0,1) at exit1+0x35d sys/kern/kern_exit.c:202
sys_exit(ffff8000230e1cf0,ffff80002b4d52d0,ffff80002b4d5330) at sys_exit+0x16 sys/kern/kern_exit.c:95
syscall(ffff80002b4d53a0) at syscall+0x44e sys/arch/amd64/amd64/trap.c:585
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7f7ffffed9e0, count: 1
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