[ 237.3530897] panic: kernel diagnostic assertion "sn->sn_opencnt" failed: file "/syzkaller/managers/ci2-netbsd/kernel/sys/miscfs/specfs/spec_vnops.c", line 1665 
[ 237.3749417] cpu0: Begin traceback...
[ 237.3830813] vpanic() at netbsd:vpanic+0x282 sys/kern/subr_prf.c:293
[ 237.4230789] _sub_D_65535_0() at netbsd:_sub_D_65535_0+-0x34c4
[ 237.4530789] spec_close() at netbsd:spec_close+0x632 sys/miscfs/specfs/spec_vnops.c:1665
[ 237.4830816] VOP_CLOSE() at netbsd:VOP_CLOSE+0xfc sys/kern/vnode_if.c:605
[ 237.5130790] cnclose() at netbsd:cnclose+0xa7 sys/dev/cons.c:159
[ 237.5430789] cdev_close() at netbsd:cdev_close+0x1c9 sys/kern/subr_devsw.c:1200
[ 237.5730796] spec_close() at netbsd:spec_close+0x3d9 sys/miscfs/specfs/spec_vnops.c:1710
[ 237.6130786] VOP_CLOSE() at netbsd:VOP_CLOSE+0xfc sys/kern/vnode_if.c:605
[ 237.6430769] vn_close() at netbsd:vn_close+0x52 sys/kern/vfs_vnops.c:480
[ 237.6730766] closef() at netbsd:closef+0x152 sys/kern/kern_descrip.c:832
[ 237.7030799] fd_free() at netbsd:fd_free+0x528 sys/kern/kern_descrip.c:1571
[ 237.7330781] exit1() at netbsd:exit1+0x306 sys/kern/kern_exit.c:301
[ 237.7630764] sys_exit() at netbsd:sys_exit+0x92 sys/kern/kern_exit.c:180
[ 237.7930776] syscall() at netbsd:syscall+0x25a sy_call sys/sys/syscallvar.h:65 [inline]
[ 237.7930776] syscall() at netbsd:syscall+0x25a sy_invoke sys/sys/syscallvar.h:94 [inline]
[ 237.7930776] syscall() at netbsd:syscall+0x25a sys/arch/x86/x86/syscall.c:138
[ 237.8043071] --- syscall (number 1) ---
[ 237.8160487] netbsd:syscall+0x25a:
[ 237.8249995] cpu0: End traceback...
[ 237.8249995] fatal breakpoint trap in supervisor mode
[ 237.8340953] trap type 1 code 0 rip 0xffffffff80220a4d cs 0x8 rflags 0x282 cr2 0x786500a7cc50 ilevel 0 rsp 0xffffd781a6cfd650
[ 237.8452716] curlwp 0xffffd78012cbb180 pid 14054.14054 lowest kstack 0xffffd781a6cf62c0
[ 237.8531533] uvm_fault(0xffffd78012c8a740, 0xffff900000000000, 1) -> e
[ 237.8531533] fatal page fault in supervisor mode
[ 237.8531533] trap type 6 code 0 rip 0xffffffff81b8407b cs 0x8 rflags 0x10283 cr2 0xffff90000000003d ilevel 0x8 rsp 0xffffd781a6cfd170
[ 237.8531533] curlwp 0xffffd78012cbb180 pid 14054.14054 lowest kstack 0xffffd781a6cf62c0
kernel: page fault trap, code=0
[ 237.8531533] uvm_fault(0xffffd78012c8a740, 0xffff900000000000, 1) -> e
[ 237.8531533] fatal page fault in supervisor mode
[ 237.8531533] trap type 6 code 0 rip 0xffffffff81b8407b cs 0x8 rflags 0x10283 cr2 0xffff90000000003d ilevel 0x8 rsp 0xffffd781a6cfcc90
[ 237.8531533] curlwp 0xffffd78012cbb180 pid 14054.14054 lowest kstack 0xffffd781a6cf62c0
kernel: page fault trap, code=0
[ 237.8531533] uvm_fault(0xffffd78012c8a740, 0xffff900000000000, 1) -> e
[ 237.8531533] fatal page fault in supervisor mode
[ 237.8531533] trap type 6 code 0 rip 0xffffffff81b8407b cs 0x8 rflags 0x10283 cr2 0xffff90000000003d ilevel 0x8 rsp 0xffffd781a6cfc7b0
[ 237.8531533] curlwp 0xffffd78012cbb180 pid 14054.14054 lowest kstack 0xffffd781a6cf62c0
kernel: page fault trap, code=0
[ 237.8531533] uvm_fault(0xffffd78012c8a740, 0xffff900000000000, 1) -> e
[ 237.8531533] fatal page fault in supervisor mode
[ 237.8531533] trap type 6 code 0 rip 0xffffffff81b8407b cs 0x8 rflags 0x10283 cr2 0xffff90000000003d ilevel 0x8 rsp 0xffffd781a6cfc2d0
[ 237.8531533] curlwp 0xffffd78012cbb180 pid 14054.14054 lowest kstack 0xffffd781a6cf62c0
kernel: page fault trap, code=0
[ 237.8531533] uvm_fault(0xffffd78012c8a740, 0xffff900000000000, 1) -> e
[ 237.8531533] fatal page fault in supervisor mode
[ 237.8531533] trap type 6 code 0 rip 0xffffffff81b8407b cs 0x8 rflags 0x10283 cr2 0xffff90000000003d ilevel 0x8 rsp 0xffffd781a6cfbdf0
[ 237.8531533] curlwp 0xffffd78012cbb180 pid 14054.14054 lowest kstack 0xffffd781a6cf62c0
kernel: page fault trap, code=0
[ 237.8531533] uvm_fault(0xffffd78012c8a740, 0xffff900000000000, 1) -> e
[ 237.8531533] fatal page fault in supervisor mode
[ 237.8531533] trap type 6 code 0 rip 0xffffffff81b8407b cs 0x8 rflags 0x10283 cr2 0xffff90000000003d ilevel 0x8 rsp 0xffffd781a6cfb910
[ 237.8531533] curlwp 0xffffd78012cbb180 pid 14054.14054 lowest kstack 0xffffd781a6cf62c0
kernel: page fault trap, code=0
[ 237.8531533] uvm_fault(0xffffd78012c8a740, 0xffff900000000000, 1) -> e
[ 237.8531533] fatal page fault in supervisor mode
[ 237.8531533] trap type 6 code 0 rip 0xffffffff81b8407b cs 0x8 rflags 0x10283 cr2 0xffff90000000003d ilevel 0x8 rsp 0xffffd781a6cfb430
[ 237.8531533] curlwp 0xffffd78012cbb180 pid 14054.14054 lowest kstack 0xffffd781a6cf62c0
kernel: page fault trap, code=0
[ 237.8531533] uvm_fault(0xffffd78012c8a740, 0xffff900000000000, 1) -> e
[ 237.8531533] fatal page fault in supervisor mode
[ 237.8531533] trap type 6 code 0 rip 0xffffffff81b8407b cs 0x8 rflags 0x10283 cr2 0xffff90000000003d ilevel 0x8 rsp 0xffffd781a6cfaf50
[ 237.8531533] curlwp 0xffffd78012cbb180 pid 14054.14054 lowest kstack 0xffffd781a6cf62c0
kernel: page fault trap, code=0
[ 237.8531533] uvm_fault(0xffffd78012c8a740, 0xffff900000000000, 1) -> e
[ 237.8531533] fatal page fault in supervisor mode
[ 237.8531533] trap type 6 code 0 rip 0xffffffff81b8407b cs 0x8 rflags 0x10283 cr2 0xffff90000000003d ilevel 0x8 rsp 0xffffd781a6cfaa70
[ 237.8531533] curlwp 0xffffd78012cbb180 pid 14054.14054 lowest kstack 0xffffd781a6cf62c0
kernel: page fault trap, code=0
[ 237.8531533] uvm_fault(0xffffd78012c8a740, 0xffff900000000000, 1) -> e
[ 237.8531533] fatal page fault in supervisor mode
[ 237.8531533] trap type 6 code 0 rip 0xffffffff81b8407b cs 0x8 rflags 0x10283 cr2 0xffff90000000003d ilevel 0x8 rsp 0xffffd781a6cfa590
[ 237.8531533] curlwp 0xffffd78012cbb180 pid 14054.14054 lowest kstack 0xffffd781a6cf62c0
kernel: page fault trap, code=0
[ 237.8531533] uvm_fault(0xffffd78012c8a740, 0xffff900000000000, 1) -> e
[ 237.8531533] fatal page fault in supervisor mode
[ 237.8531533] trap type 6 code 0 rip 0xffffffff81b8407b cs 0x8 rflags 0x10283 cr2 0xffff90000000003d ilevel 0x8 rsp 0xffffd781a6cfa0b0
[ 237.8531533] curlwp 0xffffd78012cbb180 pid 14054.14054 lowest kstack 0xffffd781a6cf62c0
kernel: page fault trap, code=0
[ 237.8531533] uvm_fault(0xffffd78012c8a740, 0xffff900000000000, 1) -> e
[ 237.8531533] fatal page fault in supervisor mode
[ 237.8531533] trap type 6 code 0 rip 0xffffffff81b8407b cs 0x8 rflags 0x10283 cr2 0xffff90000000003d ilevel 0x8 rsp 0xffffd781a6cf9bd0
[ 237.8531533] curlwp 0xffffd78012cbb180 pid 14054.14054 lowest kstack 0xffffd781a6cf62c0
kernel: page fault trap, code=0
[ 237.8531533] uvm_fault(0xffffd78012c8a740, 0xffff900000000000, 1) -> e
[ 237.8531533] fatal page fault in supervisor mode
[ 237.8531533] trap type 6 code 0 rip 0xffffffff81b8407b cs 0x8 rflags 0x10283 cr2 0xffff90000000003d ilevel 0x8 rsp 0xffffd781a6cf96f0
[ 237.8531533] curlwp 0xffffd78012cbb180 pid 14054.14054 lowest kstack 0xffffd781a6cf62c0
kernel: page fault trap, code=0
[ 237.8531533] uvm_fault(0xffffd78012c8a740, 0xffff900000000000, 1) -> e
[ 237.8531533] fatal page fault in supervisor mode
[ 237.8531533] trap type 6 code 0 rip 0xffffffff81b8407b cs 0x8 rflags 0x10283 cr2 0xffff90000000003d ilevel 0x8 rsp 0xffffd781a6cf9210
[ 237.8531533] curlwp 0xffffd78012cbb180 pid 14054.14054 lowest kstack 0xffffd781a6cf62c0
kernel: page fault trap, code=0
[ 237.8531533] uvm_fault(0xffffd78012c8a740, 0xffff900000000000, 1) -> e
[ 237.8531533] fatal page fault in supervisor mode
[ 237.8531533] trap type 6 code 0 rip 0xffffffff81b8407b cs 0x8 rflags 0x10283 cr2 0xffff90000000003d ilevel 0x8 rsp 0xffffd781a6cf8d30
[ 237.8531533] curlwp 0xffffd78012cbb180 pid 14054.14054 lowest kstack 0xffffd781a6cf62c0
kernel: page fault trap, code=0