witness: lock order reversal: 1st 0xffff800020b3b5a0 &pr->ps_mtx (&pr->ps_mtx) 2nd 0xffffffff8236c9d8 &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+0x10 sys/kern/kern_resource.c:417 #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{0}> ddb{0}> set $lines = 0 ddb{0}> set $maxwidth = 0 ddb{0}> show panic the kernel did not panic ddb{0}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 witness_checkorder(ffffffff8236c9d8,9,0) at witness_checkorder+0xffc witness_debugger sys/kern/subr_witness.c:2504 [inline] witness_checkorder(ffffffff8236c9d8,9,0) at witness_checkorder+0xffc sys/kern/subr_witness.c:1084 __mp_lock(ffffffff8236c7d0) at __mp_lock+0xa1 schedclock(ffff800020b38720) at schedclock+0x99 sys/kern/sched_bsd.c:547 hardclock(ffff800025027bd0) 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,ffff800020b3b590,0,ffff800020b3b4e0,2000) at Xresume_lapic_ltimer+0x26 calcru(ffff800020b3b608,ffff800020b3b590,10,ffff800025027c88) at calcru+0x10 sys/kern/kern_resource.c:417 exit1(ffff800020b38720,0,1) at exit1+0x737 sys/kern/kern_exit.c:301 sys_exit(ffff800020b38720,ffff800025027d60,ffff800025027dd0) at sys_exit+0x17 sys/kern/kern_exit.c:94 syscall(ffff800025027e40) at syscall+0x552 mi_syscall sys/sys/syscall_mi.h:99 [inline] syscall(ffff800025027e40) at syscall+0x552 sys/arch/amd64/amd64/trap.c:574 Xsyscall(6,1,0,1,0,7f7ffffeb6a4) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffeb670, count: -12 ddb{0}> show registers rdi 0x3 rsi 0xffffffff821c7a20 __sancov_gen_cov_switch_values.122 rbp 0xffff8000250279d0 rbx 0x3 rdx 0xffffffff821cdff0 cpu_info_full_primary+0x1ff0 rcx 0x3 rax 0xffffffff821cdff0 cpu_info_full_primary+0x1ff0 r8 0xffffffff813b9985 witness_checkorder+0xfd5 r9 0x5 r10 0x3 r11 0x6a307b718ceb1d25 r12 0xfffffd8002662340 r13 0xc r14 0xffffffff8230ae90 w_lodata+0x49850 r15 0xffffffff82318670 w_lodata+0x57030 rip 0xffffffff81e8beb8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff8000250279c0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor.0) pid=308607 stat=dead flags process=1018 proc=2000 pri=50, usrpri=77, nice=20 forw=0xffffffffffffffff, list=0xffffffffffffffff,0xffffffffffffffff process=0xffff800020b3b4e0 user=0xffff800025022000, vmspace=0xfffffd807effe5a0 estcpu=27, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 77625 204812 31806 32767 3 0x90 nanosleep syz-executor.0 31806 377302 29672 0 3 0x82 wait syz-executor.0 58338 455356 6602 32767 3 0x10 biowait syz-executor.1 6602 302581 29672 0 3 0x82 wait syz-executor.1 33798 283054 0 0 3 0x14200 bored sosplice 29672 105956 6726 0 3 0x82 thrsleep syz-fuzzer 29672 205424 6726 0 3 0x4000082 nanosleep syz-fuzzer 29672 125709 6726 0 3 0x4000082 thrsleep syz-fuzzer 29672 419672 6726 0 3 0x4000082 kqread syz-fuzzer 29672 467209 6726 0 3 0x4000082 thrsleep syz-fuzzer 29672 442627 6726 0 3 0x4000082 thrsleep syz-fuzzer 29672 134447 6726 0 3 0x4000082 thrsleep syz-fuzzer 29672 214671 6726 0 3 0x4000082 nanosleep syz-fuzzer 29672 458703 6726 0 3 0x4000082 thrsleep syz-fuzzer 29672 335860 6726 0 3 0x4000082 thrsleep syz-fuzzer 6726 253936 10351 0 3 0x10008a pause ksh 10351 150847 15698 0 3 0x92 select sshd 9540 463408 1 0 3 0x100083 ttyin getty 15698 329434 1 0 3 0x80 select sshd 44876 202862 7613 73 7 0x100090 syslogd 7613 312920 1 0 3 0x100082 netio syslogd 58277 146628 1 77 3 0x100090 poll dhclient 43943 30190 1 0 3 0x80 poll dhclient 90389 41638 0 0 3 0x14200 pgzero zerothread 73124 99555 0 0 3 0x14200 aiodoned aiodoned 93215 79114 0 0 3 0x14200 syncer update 12942 251037 0 0 3 0x14200 cleaner cleaner 81706 73276 0 0 2 0x14200 reaper 44892 4559 0 0 3 0x14200 pgdaemon pagedaemon 86481 287635 0 0 3 0x14200 bored crynlk 62240 454600 0 0 3 0x14200 bored crypto 69739 155347 0 0 3 0x40014200 acpi0 acpi0 68068 460396 0 0 3 0x40014200 idle1 35070 116546 0 0 3 0x14200 bored softnet 95087 297012 0 0 3 0x14200 bored systqmp 33562 226590 0 0 3 0x14200 bored systq 37445 473243 0 0 3 0x40014200 bored softclock 90096 234653 0 0 3 0x40014200 idle0 61961 393007 0 0 3 0x14200 bored smr 1 228070 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks CPU 0: exclusive mutex &pr->ps_mtx r = 0 (0xffff800020b3b5a0) #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 58338 (syz-executor.1) thread 0xffff800020b39788 (455356) exclusive rrwlock inode r = 0 (0xfffffd8069651f88) #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_mkdir+0xf4 sys/ufs/ufs/ufs_vnops.c:1164 #7 VOP_MKDIR+0x6a sys/kern/vfs_vops.c:449 #8 domkdirat+0x121 sys/kern/vfs_syscalls.c:2974 #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 exclusive rrwlock inode r = 0 (0xfffffd80692d4810) #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 domkdirat+0x75 sys/kern/vfs_syscalls.c:2959 #8 syscall+0x552 mi_syscall sys/sys/syscall_mi.h:99 [inline] #8 syscall+0x552 sys/arch/amd64/amd64/trap.c:574 #9 Xsyscall+0x128 ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim Kern Lim devbuf 9459 6321K 6321K 78643K 10601 0 0 pcb 23 9K 10K 78643K 614 0 0 rtable 105 3K 3K 78643K 694 0 0 ifaddr 34 10K 10K 78643K 102 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 2K 78643K 41 0 0 iov 0 0K 32K 78643K 53 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1209 76K 76K 78643K 1611 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 11 0 0 VM map 2 1K 1K 78643K 2 0 0 sem 12 0K 0K 78643K 52 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1808 196K 290K 78643K 12628 0 0 file desc 6 17K 33K 78643K 924 0 0 sigio 0 0K 0K 78643K 19 0 0 proc 41 38K 70K 78643K 830 0 0 subproc 34 2K 2K 78643K 221 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 94 0 0 in_multi 33 2K 2K 78643K 193 0 0 ether_multi 1 0K 0K 78643K 13 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 54 238K 238K 78643K 54 0 0 exec 0 0K 1K 78643K 358 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 92 21K 29K 78643K 3818 0 0 UVM aobj 33 3K 3K 78643K 41 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 55 0 0 NDP 5 0K 0K 78643K 42 0 0 temp 103 2729K 2809K 78643K 6223 0 0 kqueue 0 0K 0K 78643K 6 0 0 SYN cache 2 16K 16K 78643K 2 0 0 ddb{0}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle arp 64 28 0 22 1 0 1 1 0 8 0 inpcbpl 280 457 0 450 1 0 1 1 0 8 0 plimitpl 152 73 0 64 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtentry 112 166 0 122 2 0 2 2 0 8 0 syncache 264 4 0 4 1 1 0 1 0 8 0 tcpcb 544 196 0 192 1 0 1 1 0 8 0 nd6 48 39 0 33 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 676 0 484 12 0 12 12 0 8 0 art_table 32 677 0 484 2 0 2 2 0 8 0 art_node 16 165 0 125 1 0 1 1 0 8 0 sysvmsgpl 40 10 0 8 2 1 1 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 50 0 40 1 0 1 1 0 8 0 shmpl 112 39 0 8 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 2496 0 1071 46 0 46 46 0 8 0 ffsino 272 2496 0 1071 96 0 96 96 0 8 0 nchpl 144 3789 0 2169 61 0 61 61 0 8 0 uvmvnodes 72 2726 0 0 50 0 50 50 0 8 0 vnodes 200 2726 0 0 144 0 144 144 0 8 0 namei 1024 11929 0 11928 2 1 1 1 0 8 0 percpumem 16 30 0 0 1 0 1 1 0 8 0 scxspl 192 9683 0 9682 7 6 1 6 0 8 0 sigapl 432 1062 0 1047 3 1 2 3 0 8 0 futexpl 56 7796 0 7796 1 0 1 1 0 8 1 knotepl 112 461 0 442 1 0 1 1 0 8 0 kqueuepl 104 246 0 244 1 0 1 1 0 8 0 pipepl 112 768 0 749 5 4 1 2 0 8 0 fdescpl 488 1063 0 1048 3 0 3 3 0 8 1 filepl 152 6213 0 6117 8 3 5 6 0 8 1 lockfpl 104 127 0 127 3 2 1 1 0 8 1 lockfspl 48 43 0 43 3 2 1 1 0 8 1 sessionpl 112 28 0 18 1 0 1 1 0 8 0 pgrppl 48 40 0 30 1 0 1 1 0 8 0 ucredpl 96 1612 0 1603 1 0 1 1 0 8 0 zombiepl 144 1048 0 1047 2 1 1 1 0 8 0 processpl 888 1079 0 1047 4 0 4 4 0 8 0 procpl 600 2671 0 2629 4 0 4 4 0 8 0 srpgc 64 66 0 66 3 2 1 1 0 8 1 sosppl 128 21 0 21 3 2 1 1 0 8 1 sockpl 384 1075 0 1058 3 0 3 3 0 8 1 mcl64k 65536 4 0 0 1 0 1 1 0 8 0 mcl16k 16384 1 0 0 1 0 1 1 0 8 0 mcl12k 12288 4 0 0 1 0 1 1 0 8 0 mcl9k 9216 11 0 0 1 0 1 1 0 8 0 mcl8k 8192 2 0 0 1 0 1 1 0 8 0 mcl4k 4096 4 0 0 1 0 1 1 0 8 0 mcl2k2 2112 2 0 0 1 0 1 1 0 8 0 mcl2k 2048 117 0 0 14 0 14 14 0 8 0 mtagpl 80 1 0 0 1 0 1 1 0 8 0 mbufpl 256 194 0 0 10 0 10 10 0 8 0 bufpl 256 6663 0 1159 344 0 344 344 0 8 0 anonpl 16 112631 0 107128 59 19 40 42 0 125 15 amapchunkpl 152 7390 0 7299 22 17 5 18 0 158 1 amappl16 192 4542 0 4239 49 27 22 28 0 8 6 amappl15 184 139 0 137 2 1 1 1 0 8 0 amappl14 176 183 0 177 2 1 1 1 0 8 0 amappl13 168 118 0 116 1 0 1 1 0 8 0 amappl12 160 56 0 54 1 0 1 1 0 8 0 amappl11 152 207 0 193 1 0 1 1 0 8 0 amappl10 144 277 0 274 2 1 1 1 0 8 0 amappl9 136 804 0 799 1 0 1 1 0 8 0 amappl8 128 356 0 337 1 0 1 1 0 8 0 amappl7 120 263 0 254 1 0 1 1 0 8 0 amappl6 112 150 0 143 1 0 1 1 0 8 0 amappl5 104 218 0 206 1 0 1 1 0 8 0 amappl4 96 1280 0 1250 1 0 1 1 0 8 0 amappl3 88 252 0 241 1 0 1 1 0 8 0 amappl2 80 6953 0 6885 4 2 2 3 0 8 0 amappl1 72 35536 0 35095 23 13 10 19 0 8 0 amappl 80 3071 0 3033 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 40 0 8 1 0 1 1 0 8 0 uaddrrnd 24 1063 0 1047 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 1063 0 1047 1 0 1 1 0 8 0 vmmpekpl 168 11989 0 11960 2 0 2 2 0 8 0 vmmpepl 168 124227 0 122826 101 27 74 76 0 357 13 vmsppl 360 1062 0 1047 2 0 2 2 0 8 0 pdppl 4096 2134 0 2094 6 0 6 6 0 8 1 pvpl 32 334215 0 325515 146 34 112 114 0 265 35 pmappl 232 1062 0 1047 2 1 1 2 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 495 0 3 15 0 15 15 0 8 0