panic: kernel diagnostic assertion "ISSET(p->p_flag, P_SUSPSIG | P_SUSPSINGLE) == 0" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/kern_sig.c", line 1602 Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 311262 26691 0 0 0x4000000 1 syz-executor * 75246 23801 -1 0x40009010 0x8080000 0 syz-executor db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff834bacf2) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff834fdf8b,ffffffff83465120,642,ffffffff83447799) at __assert+0x29 sys/kern/subr_prf.c:-1 process_stop(ffff8000343944f0,8000000,1) at process_stop+0x3fe cursig(ffff800034393778,ffff80003c3edd38,0) at cursig+0x509 x86_atomic_setbits_u32 sys/arch/amd64/compile/SYZKALLER/obj/machine/atomic.h:-1 [inline] cursig(ffff800034393778,ffff80003c3edd38,0) at cursig+0x509 sys/kern/kern_sig.c:1445 userret(ffff800034393778) at userret+0x203 sys/kern/kern_sig.c:2207 syscall(ffff80003c3ede70) at syscall+0x9ce mi_syscall_return sys/sys/syscall_mi.h:203 [inline] syscall(ffff80003c3ede70) at syscall+0x9ce sys/arch/amd64/amd64/trap.c:804 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7ef8692587e0, count: 7 https://www.openbsd.org/ddb.html describes the minimum info required in bug reports. Insufficient info makes it difficult to find and fix bugs. ddb{0}> ddb{0}> set $lines = 0 ddb{0}> set $maxwidth = 0 ddb{0}> show panic *cpu0: kernel diagnostic assertion "ISSET(p->p_flag, P_SUSPSIG | P_SUSPSINGLE) == 0" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/kern_sig.c", line 1602 ddb{0}> show kasan No such command ddb{0}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff834bacf2) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff834fdf8b,ffffffff83465120,642,ffffffff83447799) at __assert+0x29 sys/kern/subr_prf.c:-1 process_stop(ffff8000343944f0,8000000,1) at process_stop+0x3fe cursig(ffff800034393778,ffff80003c3edd38,0) at cursig+0x509 x86_atomic_setbits_u32 sys/arch/amd64/compile/SYZKALLER/obj/machine/atomic.h:-1 [inline] cursig(ffff800034393778,ffff80003c3edd38,0) at cursig+0x509 sys/kern/kern_sig.c:1445 userret(ffff800034393778) at userret+0x203 sys/kern/kern_sig.c:2207 syscall(ffff80003c3ede70) at syscall+0x9ce mi_syscall_return sys/sys/syscall_mi.h:203 [inline] syscall(ffff80003c3ede70) at syscall+0x9ce sys/arch/amd64/amd64/trap.c:804 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7ef8692587e0, count: -8 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff80003c3edb50 rbx 0xffffffff83966e07 cpu_info_full_primary+0x2e07 rdx 0 rcx 0xffff800034393778 rax 0xffffffff83965ff0 cpu_info_full_primary+0x1ff0 r8 0x101010101010101 r9 0x8080808080808080 r10 0x1ce3d801b0e66d17 r11 0x64b1fbf6a99dca1f r12 0xffffffff83966c08 cpu_info_full_primary+0x2c08 r13 0 r14 0 r15 0x1 rip 0xffffffff832aac35 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80003c3edb40 ss 0x10 db_enter+0x25: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor) tid=75246 pid=23801 tcnt=4 stat=onproc flags process=40009010 proc=8080000 runpri=66, usrpri=57, slppri=17, nice=20 wchan=0x0, wmesg=, ps_single=0xffff8000343927e8 scnt=3 ecnt=0 forw=0xffffffffffffffff, list=0xffff800045fef4d8,0xffff8000343934f0 process=0xffff8000343944f0 user=0xffff80003c3e8000, vmspace=0xfffff9806b6ccd78 estcpu=7, cpticks=0, pctcpu=0.0, user=0, sys=0, intr=0 ddb{0}> ps PID TID PPID UID S PRLAGS PFLAGS WAIT COMMAND 26691 398807 28189 0 2 0 0 syz-executor 26691 311262 28189 0 7 0 0x4000000 syz-executor 76490 440625 98251 0 2 0 0 syz-executor 27053 15235 30667 0 2 0 0 syz-executor 27053 348530 30667 0 2 0 0x4000000 syz-executor 13599 62958 80801 0 2 0 0 syz-executor 13599 310082 80801 0 3 0 0x4000080 fsleep syz-executor 13599 489902 80801 0 2 0 0x4000000 syz-executor 22127 224325 75025 0 2 0 0 syz-executor 22127 388323 75025 0 3 0 0x4000080 fsleep syz-executor 49750 132607 86610 0 2 0x1000000 0 syz-executor 49750 208398 86610 0 2 0x1000000 0x4000000 syz-executor *23801 75246 46212 -1 7 0x40009010 0x8080000 syz-executor 23801 400509 46212 -1 2 0x40009010 0xc080000 syz-executor 23801 311407 46212 -1 2 0x40009010 0xc080080 syz-executor 23801 82428 46212 -1 3 0x40009010 0x4002000 suspend syz-executor 65425 227156 88552 0 3 0x100002 0x80 sbwait arp 88552 451145 23271 0 3 0x100002 0x88 sigsusp sh 98251 323698 21760 0 2 0x2 0 syz-executor 86610 493587 21760 0 3 0x2 0x80 nanoslp syz-executor 23271 119479 21760 0 3 0x2 0x80 wait syz-executor 80801 19566 21760 0 3 0x2 0x80 nanoslp syz-executor 46212 103746 21760 0 3 0x2 0x80 wait syz-executor 28189 115912 21760 0 3 0x2 0x80 nanoslp syz-executor 75025 48306 21760 0 3 0x2 0x80 nanoslp syz-executor 30667 449905 21760 0 3 0x2 0x80 nanoslp syz-executor 21760 68074 22488 0 3 0x2 0x80 kqread syz-executor 22488 458634 73406 0 3 0x100002 0x88 sigsusp ksh 73406 307427 16551 0 3 0x10 0x88 kqread sshd-session 16551 519720 70986 0 3 0x12 0x80 kqread sshd-session 81723 34180 1 0 3 0x100003 0x80 ttyin getty 70986 504794 1 0 3 0 0x88 kqread sshd 39109 407575 78118 74 3 0x1100012 0x80 bpf pflogd 78118 420172 1 0 3 0 0x80 sbwait pflogd 83315 481482 26101 73 3 0x1100010 0x80 kqread syslogd 26101 458868 1 0 3 0x100002 0x80 sbwait syslogd 37923 62202 1 0 3 0x100000 0x80 kqread resolvd 5189 179473 9921 77 3 0x100012 0x80 kqread dhcpleased 74354 462123 9921 77 3 0x100012 0x80 kqread dhcpleased 9921 434247 1 0 3 0 0x80 kqread dhcpleased 66752 472804 0 0 3 0x14000 0x200 bored smr 56477 133748 0 0 2 0x14000 0x200 zerothread 89330 139823 0 0 3 0x14000 0x200 aiodoned aiodoned 1422 181042 0 0 3 0x14000 0x200 syncer update 59440 424496 0 0 3 0x14000 0x200 cleaner cleaner 3982 470091 0 0 3 0x14000 0x200 reaper reaper 61259 190438 0 0 3 0x14000 0x200 pgdaemon pagedaemon 67819 413119 0 0 3 0x14000 0x200 bored viomb 46761 147934 0 0 3 0x14000 0x40000200 acpi0 acpi0 60310 29862 0 0 3 0x14000 0x40000200 idle1 93039 90983 0 0 3 0x14000 0x200 bored softnet1 97070 210848 0 0 3 0x14000 0x200 bored softnet0 30204 148887 0 0 3 0x14000 0x200 smrbar systqmp 96477 492799 0 0 3 0x14000 0x200 bored systq 83958 313333 0 0 3 0x14000 0x200 tmoslp softclockmp 30739 22196 0 0 3 0x14000 0x40000200 tmoslp softclock 97367 261852 0 0 3 0x14000 0x40000200 idle0 1 384624 0 0 3 0x2 0x80 wait init 0 0 -1 0 3 0x10000 0x200 scheduler swapper ddb{0}> show all locks CPU 0: exclusive mutex &sched_lock r = 0 (0xffffffff839ef3a8) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 mtx_enter+0x4b4 sys/kern/kern_lock.c:487 #2 cursig+0x4ee sys/kern/kern_sig.c:1444 #3 userret+0x203 sys/kern/kern_sig.c:2207 #4 syscall+0x9ce mi_syscall_return sys/sys/syscall_mi.h:203 [inline] #4 syscall+0x9ce sys/arch/amd64/amd64/trap.c:804 #5 Xsyscall+0x128 exclusive mutex &pr->ps_mtx r = 0 (0xffff800034394608) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 mtx_enter+0x4b4 sys/kern/kern_lock.c:487 #2 cursig+0x4c2 sys/kern/kern_sig.c:1440 #3 userret+0x203 sys/kern/kern_sig.c:2207 #4 syscall+0x9ce mi_syscall_return sys/sys/syscall_mi.h:203 [inline] #4 syscall+0x9ce sys/arch/amd64/amd64/trap.c:804 #5 Xsyscall+0x128 Process 26691 (syz-executor) thread 0xffff800038bc07f0 (398807) exclusive rwlock amaplk r = 0 (0xfffff9806df12a58) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 rw_do_enter_read+0x3e8 sys/kern/kern_rwlock.c:413 #2 uvm_fault_check+0x8a9 sys/uvm/uvm_fault.c:834 #3 uvm_fault+0x106 sys/uvm/uvm_fault.c:627 #4 upageflttrap+0xa9 sys/arch/amd64/amd64/trap.c:192 #5 usertrap+0x430 sys/arch/amd64/amd64/trap.c:640 #6 recall_trap+0x8 shared rwlock vmmaplk r = 0 (0xfffff9806cf16118) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 rw_do_enter_read+0x3e8 sys/kern/kern_rwlock.c:413 #2 uvmfault_lookup+0x122 sys/uvm/uvm_fault.c:1880 #3 uvm_fault_check+0x4f sys/uvm/uvm_fault.c:693 #4 uvm_fault+0x106 sys/uvm/uvm_fault.c:627 #5 upageflttrap+0xa9 sys/arch/amd64/amd64/trap.c:192 #6 usertrap+0x430 sys/arch/amd64/amd64/trap.c:640 #7 recall_trap+0x8 Process 30204 (systqmp) thread 0xffff800045ffe530 (148887) shared rwlock systqmp r = 0 (0xffffffff838e3108) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 taskq_thread+0x12a sys/kern/kern_task.c:442 #2 proc_trampoline+0x10 ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 11058 12094K 12417K 166960K 12474 0 pcb 17 12K 12K 166960K 51 0 rtable 212 7K 7K 166960K 354 0 pf 34 17K 24K 166960K 73 0 ifaddr 42 7K 7K 166960K 52 0 ifgroup 55 2K 2K 166960K 70 0 sysctl 1 1K 9K 166960K 5 0 counters 70 37K 37K 166960K 82 0 ioctlops 0 0K 4K 166960K 1574 0 iov 0 0K 16K 166960K 4 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1326 83K 84K 166960K 1502 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 20K 24K 166960K 7 0 VM map 2 1K 1K 166960K 2 0 sem 12 0K 0K 166960K 70 0 dirhash 12 2K 2K 166960K 12 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 19 69K 85K 166960K 249 0 sigio 0 0K 0K 166960K 2 0 proc 72 115K 164K 166960K 555 0 subproc 72 4K 4K 166960K 72 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 9 0 in_multi 92 6K 6K 166960K 96 0 ether_multi 1 0K 0K 166960K 1 0 mrt 0 0K 0K 166960K 4 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 55 254K 254K 166960K 55 0 exec 0 0K 1K 166960K 401 0 fusefs mount 1 32K 32K 166960K 1 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 241 169K 180K 166960K 4091 0 UVM aobj 7 2K 2K 166960K 7 0 pinsyscall 45 90K 102K 166960K 1396 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 40 0 NDP 12 0K 1K 166960K 31 0 temp 76 9124K 9140K 166960K 6965 0 kqueue 14 22K 29K 166960K 47 0 SYN cache 2 16K 16K 166960K 2 0 ddb{0}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle plcache 128 28 0 0 1 0 1 1 0 8 0 rtpcb 120 42 0 38 1 0 1 1 0 8 0 rtentry 176 105 0 12 5 0 5 5 0 8 0 unpcb 144 234 0 216 6 0 6 6 0 8 5 syncache 336 5 0 5 1 0 1 1 0 8 1 tcpcb 736 33 0 28 1 0 1 1 0 8 0 arp 136 17 0 0 1 0 1 1 0 8 0 inpcb 328 153 0 145 2 0 2 2 0 8 1 nd6 152 22 0 0 1 0 1 1 0 8 0 pkpcb 40 1 0 1 1 0 1 1 0 8 1 kcovpl 48 8 0 0 1 0 1 1 0 8 0 ppxss 1192 4 0 4 1 0 1 1 0 8 1 pfosfp 40 1428 0 1005 5 0 5 5 0 8 0 pfosfpen 112 1428 0 714 21 0 21 21 0 8 0 pfsrclim 320 1 0 1 1 0 1 1 0 8 1 pfanchor 1288 3 0 3 1 0 1 1 0 8 1 pfstitem 24 26 0 0 1 0 1 1 0 8 0 pfstkey 128 26 0 0 1 0 1 1 0 8 0 pfstate 448 26 0 0 3 0 3 3 0 8 0 pfrule 1360 22 0 17 2 1 1 2 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 457 0 41 29 0 29 29 0 8 1 art_table 40 458 0 41 5 0 5 5 0 8 0 art_node 32 105 0 10 1 0 1 1 0 8 0 semapl 72 68 0 58 1 0 1 1 0 8 0 shmpl 112 4 0 0 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 1798 0 332 93 0 93 93 0 8 0 ffsino 296 1798 0 332 114 0 114 114 0 8 0 nchpl 144 2151 0 449 64 0 64 64 0 8 0 vnodes 216 1979 0 0 110 0 110 110 0 8 0 namei 1024 7027 0 7027 2 0 2 2 0 8 2 percpumem 16 57 0 6 1 0 1 1 0 8 0 kstatmem 264 37 0 10 3 0 3 3 0 8 1 scsiplug 72 1 0 1 1 0 1 1 0 8 1 scxspl 216 7324 0 7324 4 3 1 3 1 8 1 plimitpl 152 44 0 27 1 0 1 1 0 8 0 sigapl 424 566 0 517 7 0 7 7 0 8 0 knotepl 120 284 0 0 9 0 9 9 0 8 0 kqueuepl 224 55 0 44 1 0 1 1 0 8 0 pipepl 344 142 0 115 3 0 3 3 0 8 0 fdescpl 528 550 0 517 3 0 3 3 0 8 0 filepl 160 2479 0 2263 18 0 18 18 0 8 7 lockfpl 104 56 0 53 1 0 1 1 0 8 0 lockfspl 48 29 0 26 1 0 1 1 0 8 0 sessionpl 144 32 0 23 1 0 1 1 0 8 0 pgrppl 48 41 0 24 1 0 1 1 0 8 0 ucredpl 104 289 0 275 1 0 1 1 0 8 0 zombiepl 144 517 0 517 1 0 1 1 0 8 1 processpl 1232 566 0 517 5 0 5 5 0 8 0 procpl 664 770 0 712 6 0 6 6 0 8 0 sockpl 752 431 0 401 17 2 15 17 0 8 11 mcl64k 65536 3 0 0 1 0 1 1 0 8 0 mcl16k 16384 3 0 0 1 0 1 1 0 8 0 mcl9k128 9344 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 3 0 0 1 0 1 1 0 8 0 mcl4k 4096 129 0 0 17 0 17 17 0 8 0 mcl2k 2048 20 0 0 3 0 3 3 0 8 0 mextrefs 64 23 0 0 1 0 1 1 0 8 0 mtagpl 96 1 0 0 1 0 1 1 0 8 0 mbufpl 256 204 0 0 13 0 13 13 0 8 0 bufpl 272 2580 0 105 165 0 165 165 0 8 0 anonpl 32 5355 0 0 44 0 44 44 0 247 0 amapchunkpl 152 11752 0 11253 23 0 23 23 0 158 2 amappl16 200 1570 0 1545 5 2 3 5 0 8 1 amappl15 192 4 0 4 1 1 0 1 0 8 0 amappl14 184 429 0 427 1 0 1 1 0 8 0 amappl13 176 123 0 110 1 0 1 1 0 8 0 amappl12 168 794 0 763 2 0 2 2 0 8 0 amappl11 160 4 0 4 1 1 0 1 0 8 0 amappl10 152 65 0 51 1 0 1 1 0 8 0 amappl9 144 280 0 280 1 1 0 1 0 8 0 amappl8 136 101 0 99 1 0 1 1 0 8 0 amappl7 128 142 0 128 1 0 1 1 0 8 0 amappl6 120 166 0 164 1 0 1 1 0 8 0 amappl5 112 107 0 97 1 0 1 1 0 8 0 amappl4 104 308 0 289 1 0 1 1 0 8 0 amappl3 96 2093 0 1991 3 0 3 3 0 8 0 amappl2 88 663 0 585 2 0 2 2 0 8 0 amappl1 80 10772 0 10142 15 0 15 15 0 8 0 amappl 88 3362 0 3198 5 0 5 5 0 92 0 uvmvnodes 80 101 0 0 3 0 3 3 0 8 0 dma4096 4096 1 0 1 1 1 0 1 0 8 0 dma1024 1024 1 0 0 1 0 1 1 0 8 0 dma512 512 1 0 1 1 0 1 1 0 8 1 dma256 256 6 0 6 1 1 0 1 0 8 0 dma128 128 253 0 253 1 1 0 1 0 8 0 dma64 64 6 0 6 1 1 0 1 0 8 0 dma32 32 7 0 7 1 1 0 1 0 8 0 dma16 16 19 0 18 1 0 1 1 0 8 0 aobjpl 72 6 0 0 1 0 1 1 0 8 0 uaddrrnd 24 550 0 517 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 550 0 517 1 0 1 1 0 8 0 vmmpekpl 168 6504 0 6472 3 0 3 3 0 8 1 vmmpepl 168 43729 0 41753 89 0 89 89 0 357 2 vmsppl 488 549 0 517 5 0 5 5 0 8 0 rwobjpl 80 15307 0 14230 24 0 24 24 0 8 0 pdppl 4096 1107 0 1034 95 22 73 83 0 8 0 pvpl 32 10778 0 0 88 1 87 88 0 265 0 pmappl 256 549 0 517 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 438 0 25 12 0 12 12 0 8 0 ddb{0}> machine ddbcpu 0 Invalid cpu 0 ddb{0}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff834bacf2) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff834fdf8b,ffffffff83465120,642,ffffffff83447799) at __assert+0x29 sys/kern/subr_prf.c:-1 process_stop(ffff8000343944f0,8000000,1) at process_stop+0x3fe cursig(ffff800034393778,ffff80003c3edd38,0) at cursig+0x509 x86_atomic_setbits_u32 sys/arch/amd64/compile/SYZKALLER/obj/machine/atomic.h:-1 [inline] cursig(ffff800034393778,ffff80003c3edd38,0) at cursig+0x509 sys/kern/kern_sig.c:1445 userret(ffff800034393778) at userret+0x203 sys/kern/kern_sig.c:2207 syscall(ffff80003c3ede70) at syscall+0x9ce mi_syscall_return sys/sys/syscall_mi.h:203 [inline] syscall(ffff80003c3ede70) at syscall+0x9ce sys/arch/amd64/amd64/trap.c:804 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7ef8692587e0, count: -8 ddb{0}> machine ddbcpu 1 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffff80002999dff0) at x86_ipi_db+0x27 sys/arch/amd64/amd64/db_interface.c:394 x86_ipi_handler() at x86_ipi_handler+0xd9 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x27 __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0xf kd_curproc sys/dev/kcov.c:580 [inline] __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0xf sys/dev/kcov.c:153 kqueue_scan(ffff80003c3f3870,2,ffff80003c3f3770,0,ffff800038bc1a18,ffff80003c3f3a1c) at kqueue_scan+0x27d sys/kern/kern_event.c:1663 dopselect(ffff800038bc1a18,40,200000000100,2000000024c0,0,0,e25f799061f45701,ffff800038bc1a18) at dopselect+0x53e sys/kern/sys_generic.c:695 sys_select(ffff800038bc1a18,ffff80003c3f3c00,ffff80003c3f3b50) at sys_select+0x1d1 sys/kern/sys_generic.c:556 syscall(ffff80003c3f3c00) at syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003c3f3c00) at syscall+0xbd4 sys/arch/amd64/amd64/trap.c:783 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x96177a41de0, count: 6 ddb{1}> trace x86_ipi_db(ffff80002999dff0) at x86_ipi_db+0x27 sys/arch/amd64/amd64/db_interface.c:394 x86_ipi_handler() at x86_ipi_handler+0xd9 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x27 __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0xf kd_curproc sys/dev/kcov.c:580 [inline] __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0xf sys/dev/kcov.c:153 kqueue_scan(ffff80003c3f3870,2,ffff80003c3f3770,0,ffff800038bc1a18,ffff80003c3f3a1c) at kqueue_scan+0x27d sys/kern/kern_event.c:1663 dopselect(ffff800038bc1a18,40,200000000100,2000000024c0,0,0,e25f799061f45701,ffff800038bc1a18) at dopselect+0x53e sys/kern/sys_generic.c:695 sys_select(ffff800038bc1a18,ffff80003c3f3c00,ffff80003c3f3b50) at sys_select+0x1d1 sys/kern/sys_generic.c:556 syscall(ffff80003c3f3c00) at syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003c3f3c00) at syscall+0xbd4 sys/arch/amd64/amd64/trap.c:783 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x96177a41de0, count: -9