witness: lock order reversal: 1st 0xffff800020b8d5a8 &pr->ps_mtx (&pr->ps_mtx) 2nd 0xffffffff82384c80 &sched_lock (&sched_lock) lock order "&sched_lock"(sched_lock) -> "&pr->ps_mtx"(mutex) first seen at: #0 witness_checkorder+0x6a7 sys/kern/subr_witness.c:877 #1 mtx_enter+0x3a sys/kern/kern_lock.c:265 #2 tuagg+0x32 sys/kern/kern_resource.c:360 #3 mi_switch+0x1c7 x86_atomic_clearbits_u32 sys/arch/amd64/compile/SYZKALLER/obj/machine/atomic.h:298 [inline] #3 mi_switch+0x1c7 sys/kern/sched_bsd.c:392 #4 sleep_finish+0x110 sys/kern/kern_synch.c:303 #5 msleep+0x1af sleep_finish_timeout sys/kern/kern_synch.c:327 [inline] #5 msleep+0x1af sleep_finish_all sys/kern/kern_synch.c:157 [inline] #5 msleep+0x1af sys/kern/kern_synch.c:220 #6 scsi_xs_sync+0x14f sys/scsi/scsi_base.c:1339 #7 scsi_start+0x86 sys/scsi/scsi_base.c:938 #8 sdopen+0x22b sys/scsi/sd.c:400 #9 spec_open+0x41c sys/kern/spec_vnops.c:158 #10 VOP_OPEN+0x6a sys/kern/vfs_vops.c:153 #11 sr_meta_native_bootprobe+0xd3 sys/dev/softraid.c:1038 #12 sr_boot_assembly+0x1aa sys/dev/softraid.c:1202 #13 sr_attach+0x183 sys/dev/softraid.c:1822 #14 config_attach+0x347 sys/kern/subr_autoconf.c:404 #15 main+0x6de sys/kern/init_main.c:483 #16 longmode_hi+0x95 lock order "&pr->ps_mtx"(mutex) -> "&sched_lock"(sched_lock) first seen at: #0 witness_checkorder+0x6a7 sys/kern/subr_witness.c:877 #1 __mp_lock+0xa1 #2 schedclock+0x99 sys/kern/sched_bsd.c:547 #3 hardclock+0x1d8 sys/kern/kern_clock.c:174 #4 lapic_clockintr+0x44 sys/arch/amd64/amd64/lapic.c:425 #5 Xresume_lapic_ltimer+0x26 #6 calcru+0x5e calctsru sys/kern/kern_resource.c:391 [inline] #6 calcru+0x5e sys/kern/kern_resource.c:420 #7 exit1+0x737 sys/kern/kern_exit.c:301 #8 sys_exit+0x17 sys/kern/kern_exit.c:94 #9 syscall+0x552 mi_syscall sys/sys/syscall_mi.h:99 [inline] #9 syscall+0x552 sys/arch/amd64/amd64/trap.c:574 #10 Xsyscall+0x128 Stopped at db_enter+0x18: addq $0x8,%rsp ddb{1}> ddb{1}> set $lines = 0 ddb{1}> set $maxwidth = 0 ddb{1}> show panic the kernel did not panic ddb{1}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 witness_checkorder(ffffffff82384c80,9,0) at witness_checkorder+0xffc witness_debugger sys/kern/subr_witness.c:2504 [inline] witness_checkorder(ffffffff82384c80,9,0) at witness_checkorder+0xffc sys/kern/subr_witness.c:1084 __mp_lock(ffffffff82384a78) at __mp_lock+0xa1 schedclock(ffff800020b32bd0) at schedclock+0x99 sys/kern/sched_bsd.c:547 hardclock(ffff800022e1b2e0) at hardclock+0x1d8 sys/kern/kern_clock.c:174 lapic_clockintr(0,0) at lapic_clockintr+0x44 sys/arch/amd64/amd64/lapic.c:425 Xresume_lapic_ltimer(9,0,0,0,2,0) at Xresume_lapic_ltimer+0x26 calcru(ffff800020b8d610,fffffd807ae22cf8,fffffd807ae22d08,0) at calcru+0x5e calctsru sys/kern/kern_resource.c:391 [inline] calcru(ffff800020b8d610,fffffd807ae22cf8,fffffd807ae22d08,0) at calcru+0x5e sys/kern/kern_resource.c:420 exit1(ffff800020b32bd0,0,1) at exit1+0x737 sys/kern/kern_exit.c:301 sys_exit(ffff800020b32bd0,ffff800022e1b4f0,ffff800022e1b560) at sys_exit+0x17 sys/kern/kern_exit.c:94 syscall(ffff800022e1b5d0) at syscall+0x552 mi_syscall sys/sys/syscall_mi.h:99 [inline] syscall(ffff800022e1b5d0) at syscall+0x552 sys/arch/amd64/amd64/trap.c:574 Xsyscall(6,1,0,1,0,7f7fffff7684) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7fffff7650, count: -12 ddb{1}> show registers rdi 0x3 rsi 0xffffffff821fc9e0 __sancov_gen_cov_switch_values.122 rbp 0xffff800022e1b0e0 rbx 0x3 rdx 0xffff800020ab0ff0 rcx 0x3 rax 0xffff800020ab0ff0 r8 0xffffffff818c8c95 witness_checkorder+0xfd5 r9 0x5 r10 0x3 r11 0xf810aea24af7fe5c r12 0xfffffd8002661340 r13 0xc r14 0xffffffff82334260 w_lodata+0x49010 r15 0xffffffff823423e0 w_lodata+0x57190 rip 0xffffffff81a42468 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800022e1b0d0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor.1) pid=176519 stat=dead flags process=1018 proc=2000 pri=50, usrpri=76, nice=20 forw=0xffffffffffffffff, list=0xffffffffffffffff,0xffffffffffffffff process=0xffff800020b8d4e8 user=0xffff800022e16000, vmspace=0xfffffd807effd9d8 estcpu=36, cpticks=3, pctcpu=0.0 user=0, sys=1, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 25736 344477 82404 0 7 0 syz-executor.0 25736 512016 82404 0 3 0x4000000 biowait syz-executor.0 53074 356430 0 0 3 0x14200 bored sosplice 557 291839 88505 0 3 0x82 nanosleep syz-executor.1 82404 24056 88505 0 3 0x82 nanosleep syz-executor.0 88505 45902 87690 0 3 0x82 thrsleep syz-fuzzer 88505 263573 87690 0 3 0x4000082 thrsleep syz-fuzzer 88505 235121 87690 0 3 0x4000082 thrsleep syz-fuzzer 88505 304203 87690 0 3 0x4000082 kqread syz-fuzzer 88505 38255 87690 0 3 0x4000082 thrsleep syz-fuzzer 88505 338348 87690 0 3 0x4000082 thrsleep syz-fuzzer 88505 411696 87690 0 3 0x4000082 thrsleep syz-fuzzer 88505 353425 87690 0 3 0x4000082 thrsleep syz-fuzzer 88505 7157 87690 0 3 0x4000082 thrsleep syz-fuzzer 88505 50159 87690 0 3 0x4000082 thrsleep syz-fuzzer 87690 458360 35910 0 3 0x10008a pause ksh 35910 195532 45488 0 3 0x92 select sshd 20274 476729 1 0 3 0x100083 ttyin getty 45488 435434 1 0 3 0x80 select sshd 6041 17564 86042 74 3 0x100092 bpf pflogd 86042 135186 1 0 3 0x80 netio pflogd 1326 317016 82702 73 2 0x100090 syslogd 82702 342264 1 0 3 0x100082 netio syslogd 98388 199688 1 77 3 0x100090 poll dhclient 28818 206006 1 0 3 0x80 poll dhclient 54359 195355 0 0 2 0x14200 zerothread 47990 3646 0 0 3 0x14200 aiodoned aiodoned 51924 311296 0 0 3 0x14200 syncer update 56542 248650 0 0 3 0x14200 cleaner cleaner 78350 219830 0 0 3 0x14200 reaper reaper 31622 31494 0 0 3 0x14200 pgdaemon pagedaemon 21718 171149 0 0 3 0x14200 bored crynlk 15406 339093 0 0 3 0x14200 bored crypto 78880 304093 0 0 3 0x40014200 acpi0 acpi0 351 337017 0 0 3 0x40014200 idle1 90565 280853 0 0 3 0x14200 bored softnet 4638 101096 0 0 3 0x14200 bored systqmp 30809 215667 0 0 3 0x14200 bored systq 89537 59389 0 0 3 0x40014200 bored softclock 74714 240519 0 0 3 0x40014200 idle0 7239 524084 0 0 3 0x14200 bored smr 1 10322 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks CPU 1: exclusive mutex &pr->ps_mtx r = 0 (0xffff800020b8d5a8) #0 witness_lock+0x52e sys/kern/subr_witness.c:1161 #1 mtx_enter_try+0x102 #2 mtx_enter+0x4b sys/kern/kern_lock.c:266 #3 exit1+0x722 sys/kern/kern_exit.c:300 #4 sys_exit+0x17 sys/kern/kern_exit.c:94 #5 syscall+0x552 mi_syscall sys/sys/syscall_mi.h:99 [inline] #5 syscall+0x552 sys/arch/amd64/amd64/trap.c:574 #6 Xsyscall+0x128 Process 25736 (syz-executor.0) thread 0xffff800020b33530 (512016) exclusive rrwlock inode r = 0 (0xfffffd80678b44e8) #0 witness_lock+0x52e sys/kern/subr_witness.c:1161 #1 rw_enter+0x46d sys/kern/kern_rwlock.c:306 #2 rrw_enter+0x4f sys/kern/kern_rwlock.c:435 #3 ufs_ihashins+0x45 sys/ufs/ufs/ufs_ihash.c:140 #4 ffs_vget+0x133 sys/ufs/ffs/ffs_vfsops.c:1352 #5 ffs_inode_alloc+0x1cf sys/ufs/ffs/ffs_alloc.c:392 #6 ufs_makeinode+0xaa sys/ufs/ufs/ufs_vnops.c:1832 #7 ufs_create+0x41 sys/ufs/ufs/ufs_vnops.c:152 #8 VOP_CREATE+0x64 sys/kern/vfs_vops.c:112 #9 vn_open+0x23c sys/kern/vfs_vnops.c:112 #10 doopenat+0x28e sys/kern/vfs_syscalls.c:1138 #11 syscall+0x552 mi_syscall sys/sys/syscall_mi.h:99 [inline] #11 syscall+0x552 sys/arch/amd64/amd64/trap.c:574 #12 Xsyscall+0x128 exclusive rrwlock inode r = 0 (0xfffffd80678b4928) #0 witness_lock+0x52e sys/kern/subr_witness.c:1161 #1 rw_enter+0x46d sys/kern/kern_rwlock.c:306 #2 rrw_enter+0x4f sys/kern/kern_rwlock.c:435 #3 VOP_LOCK+0x4b sys/kern/vfs_vops.c:602 #4 vn_lock+0x6e sys/kern/vfs_vnops.c:549 #5 vfs_lookup+0xe9 sys/kern/vfs_lookup.c:422 #6 namei+0x61c sys/kern/vfs_lookup.c:252 #7 vn_open+0x145 sys/kern/vfs_vnops.c:103 #8 doopenat+0x28e sys/kern/vfs_syscalls.c:1138 #9 syscall+0x552 mi_syscall sys/sys/syscall_mi.h:99 [inline] #9 syscall+0x552 sys/arch/amd64/amd64/trap.c:574 #10 Xsyscall+0x128 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim Kern Lim devbuf 9485 6410K 7056K 78643K 11780 0 0 pcb 25 9K 11K 78643K 367 0 0 rtable 108 4K 4K 78643K 301 0 0 ifaddr 46 11K 12K 78643K 97 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 4K 78643K 1494 0 0 iov 0 0K 32K 78643K 70 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1211 76K 77K 78643K 1710 0 0 UFS quota 1 32K 32K 78643K 1 0 0 UFS mount 5 36K 36K 78643K 5 0 0 shm 2 1K 5K 78643K 6 0 0 VM map 2 1K 1K 78643K 2 0 0 sem 12 1K 1K 78643K 59 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1808 196K 290K 78643K 12628 0 0 file desc 5 13K 25K 78643K 832 0 0 sigio 0 0K 0K 78643K 14 0 0 proc 54 51K 83K 78643K 426 0 0 subproc 32 2K 2K 78643K 34 0 0 NFS srvsock 1 0K 0K 78643K 1 0 0 NFS daemon 1 16K 16K 78643K 1 0 0 ip_moptions 0 0K 0K 78643K 53 0 0 in_multi 33 2K 2K 78643K 54 0 0 ether_multi 1 0K 0K 78643K 5 0 0 mrt 0 0K 0K 78643K 8 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 60 265K 265K 78643K 60 0 0 exec 0 0K 1K 78643K 250 0 0 pagedep 1 8K 8K 78643K 1 0 0 inodedep 1 32K 32K 78643K 1 0 0 newblk 1 0K 0K 78643K 1 0 0 VM swap 7 26K 26K 78643K 7 0 0 UVM amap 93 21K 30K 78643K 3559 0 0 UVM aobj 16 2K 2K 78643K 16 0 0 memdesc 1 4K 4K 78643K 1 0 0 crypto data 1 1K 1K 78643K 1 0 0 ip6_options 0 0K 0K 78643K 29 0 0 NDP 8 0K 0K 78643K 25 0 0 temp 144 2735K 2803K 78643K 5514 0 0 kqueue 0 0K 0K 78643K 3 0 0 SYN cache 2 16K 16K 78643K 2 0 0 ddb{1}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle arp 64 6 0 0 1 0 1 1 0 8 0 inpcbpl 280 284 0 277 1 0 1 1 0 8 0 plimitpl 152 38 0 30 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtentry 112 47 0 3 2 0 2 2 0 8 0 syncache 264 4 0 4 1 1 0 1 0 8 0 tcpqe 32 4 0 4 1 1 0 1 0 8 0 tcpcb 544 99 0 95 1 0 1 1 0 8 0 rttmr 72 2 0 2 2 1 1 1 0 8 1 nd6 48 6 0 0 1 0 1 1 0 8 0 ppxss 1128 11 0 11 4 3 1 1 0 8 1 pfosfp 40 846 0 423 5 0 5 5 0 8 0 pfosfpen 112 1428 0 714 21 0 21 21 0 8 0 pfstitem 24 16 0 7 1 0 1 1 0 8 0 pfstkey 112 16 0 7 1 0 1 1 0 8 0 pfstate 328 16 0 7 1 0 1 1 0 8 0 pfrule 1360 21 0 16 2 1 1 2 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 188 0 0 12 0 12 12 0 8 0 art_table 32 189 0 0 2 0 2 2 0 8 0 art_node 16 46 0 6 1 0 1 1 0 8 0 sysvmsgpl 40 10 0 10 4 4 0 1 0 8 0 semapl 112 57 0 47 1 0 1 1 0 8 0 shmpl 112 14 0 0 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 2629 0 1204 47 0 47 47 0 8 0 ffsino 272 2629 0 1204 96 0 96 96 0 8 0 nchpl 144 3935 0 2292 62 0 62 62 0 8 0 uvmvnodes 72 2977 0 0 55 0 55 55 0 8 0 vnodes 200 2977 0 0 157 0 157 157 0 8 0 namei 1024 10933 0 10932 2 1 1 1 0 8 0 percpumem 16 30 0 0 1 0 1 1 0 8 0 scxspl 192 11327 0 11326 8 7 1 6 0 8 0 sigapl 432 1032 0 1016 3 1 2 3 0 8 0 futexpl 56 8086 0 8086 1 0 1 1 0 8 1 knotepl 112 123 0 104 1 0 1 1 0 8 0 kqueuepl 104 133 0 131 1 0 1 1 0 8 0 pipepl 112 514 0 493 3 2 1 2 0 8 0 fdescpl 488 1033 0 1017 4 1 3 3 0 8 0 filepl 152 4905 0 4803 5 0 5 5 0 8 1 lockfpl 104 218 0 218 3 2 1 1 0 8 1 lockfspl 48 73 0 73 3 2 1 1 0 8 1 sessionpl 112 18 0 7 1 0 1 1 0 8 0 pgrppl 48 22 0 11 1 0 1 1 0 8 0 ucredpl 96 1048 0 1038 1 0 1 1 0 8 0 zombiepl 144 1017 0 1016 2 1 1 1 0 8 0 processpl 888 1049 0 1016 4 0 4 4 0 8 0 procpl 600 2780 0 2737 4 0 4 4 0 8 0 srpgc 64 2 0 2 2 1 1 1 0 8 1 sosppl 128 8 0 8 3 2 1 1 0 8 1 sockpl 384 590 0 571 4 1 3 4 0 8 1 mcl64k 65536 6 0 0 1 0 1 1 0 8 0 mcl16k 16384 2 0 0 1 0 1 1 0 8 0 mcl12k 12288 4 0 0 1 0 1 1 0 8 0 mcl9k 9216 3 0 0 1 0 1 1 0 8 0 mcl8k 8192 4 0 0 1 0 1 1 0 8 0 mcl4k 4096 5 0 0 1 0 1 1 0 8 0 mcl2k2 2112 3 0 0 1 0 1 1 0 8 0 mcl2k 2048 118 0 0 14 0 14 14 0 8 0 mtagpl 80 1 0 0 1 0 1 1 0 8 0 mbufpl 256 142 0 0 8 0 8 8 0 8 0 bufpl 256 7406 0 1189 389 0 389 389 0 8 0 anonpl 16 99960 0 89913 73 16 57 57 0 125 16 amapchunkpl 152 5462 0 5360 12 6 6 9 0 158 0 amappl16 192 4447 0 3917 51 16 35 38 0 8 8 amappl15 184 411 0 409 1 0 1 1 0 8 0 amappl14 176 449 0 445 2 1 1 1 0 8 0 amappl13 168 385 0 383 2 1 1 1 0 8 0 amappl12 160 10 0 8 1 0 1 1 0 8 0 amappl11 152 61 0 42 1 0 1 1 0 8 0 amappl10 144 72 0 68 1 0 1 1 0 8 0 amappl9 136 595 0 592 1 0 1 1 0 8 0 amappl8 128 138 0 124 1 0 1 1 0 8 0 amappl7 120 35 0 30 1 0 1 1 0 8 0 amappl6 112 60 0 52 1 0 1 1 0 8 0 amappl5 104 129 0 114 1 0 1 1 0 8 0 amappl4 96 780 0 756 1 0 1 1 0 8 0 amappl3 88 1027 0 1012 1 0 1 1 0 8 0 amappl2 80 7326 0 7246 4 2 2 3 0 8 0 amappl1 72 31861 0 31403 25 14 11 20 0 8 0 amappl 80 3029 0 2989 1 0 1 1 0 84 0 dma4096 4096 1 0 1 1 1 0 1 0 8 0 dma256 256 6 0 6 1 1 0 1 0 8 0 dma64 64 259 0 259 1 1 0 1 0 8 0 dma32 32 7 0 7 1 1 0 1 0 8 0 dma16 16 17 0 17 1 1 0 1 0 8 0 aobjpl 64 15 0 0 1 0 1 1 0 8 0 uaddrrnd 24 1033 0 1016 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 1033 0 1016 1 0 1 1 0 8 0 vmmpekpl 168 11862 0 11831 2 0 2 2 0 8 0 vmmpepl 168 115750 0 114077 102 22 80 83 0 357 7 vmsppl 360 1032 0 1016 2 0 2 2 0 8 0 pdppl 4096 2074 0 2032 7 1 6 6 0 8 0 pvpl 32 302083 0 288773 179 35 144 144 0 265 35 pmappl 232 1032 0 1016 2 1 1 2 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 541 0 5 16 0 16 16 0 8 0