witness: lock order reversal: 1st 0xffff800020b8c0d8 &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 __sanitizer_cov_trace_pc+0x40 sys/dev/kcov.c:102 #7 exit1+0x73f sys/kern/kern_exit.c:302 #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(ffff800020b9b080) at schedclock+0x99 sys/kern/sched_bsd.c:547 hardclock(ffff800022e16d00) 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,ffff800020ab0ff0,ffff800020b8c0c8,0,ffff800020b8c018,ffff800020b8c0c8) at Xresume_lapic_ltimer+0x26 __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x40 sys/dev/kcov.c:102 exit1(ffff800020b9b080,0,1) at exit1+0x73f sys/kern/kern_exit.c:302 sys_exit(ffff800020b9b080,ffff800022e16ed0,ffff800022e16f40) at sys_exit+0x17 sys/kern/kern_exit.c:94 syscall(ffff800022e16fb0) at syscall+0x552 mi_syscall sys/sys/syscall_mi.h:99 [inline] syscall(ffff800022e16fb0) at syscall+0x552 sys/arch/amd64/amd64/trap.c:574 Xsyscall(6,1,0,1,0,7f7ffffdff04) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffdfed0, count: -12 ddb{1}> show registers rdi 0x3 rsi 0xffffffff821fc9e0 __sancov_gen_cov_switch_values.122 rbp 0xffff800022e16b00 rbx 0x3 rdx 0xffff800020ab0ff0 rcx 0x3 rax 0xffff800020ab0ff0 r8 0xffffffff818c8c95 witness_checkorder+0xfd5 r9 0x5 r10 0x3 r11 0x11e9e47f75189348 r12 0xfffffd8002661340 r13 0xc r14 0xffffffff82338a90 w_lodata+0x4d840 r15 0xffffffff82342280 w_lodata+0x57030 rip 0xffffffff81a42468 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800022e16af0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor.0) pid=512384 stat=dead flags process=1008 proc=2000 pri=50, usrpri=59, nice=20 forw=0xffffffffffffffff, list=0xffffffffffffffff,0xffffffffffffffff process=0xffff800020b8c018 user=0xffff800022e12000, vmspace=0xfffffd807effd9d8 estcpu=36, cpticks=2, pctcpu=0.0 user=0, sys=1, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 97477 430088 95639 0 2 0 syz-executor.1 97477 22203 95639 0 3 0x4000000 biowait syz-executor.1 95639 167427 54323 0 3 0x82 nanosleep syz-executor.1 25908 246471 54323 0 3 0x82 nanosleep syz-executor.0 54323 455116 40532 0 3 0x82 thrsleep syz-fuzzer 54323 258410 40532 0 3 0x4000082 thrsleep syz-fuzzer 54323 343005 40532 0 3 0x4000082 thrsleep syz-fuzzer 54323 298751 40532 0 3 0x4000082 thrsleep syz-fuzzer 54323 197592 40532 0 3 0x4000082 thrsleep syz-fuzzer 54323 284183 40532 0 3 0x4000082 kqread syz-fuzzer 54323 78687 40532 0 3 0x4000082 thrsleep syz-fuzzer 54323 507564 40532 0 3 0x4000082 thrsleep syz-fuzzer 54323 29397 40532 0 3 0x4000082 thrsleep syz-fuzzer 54323 139301 40532 0 3 0x4000082 thrsleep syz-fuzzer 40532 303328 9062 0 3 0x10008a pause ksh 9062 164396 66134 0 3 0x92 select sshd 60792 184582 1 0 3 0x100083 ttyin getty 66134 281331 1 0 3 0x80 select sshd 2323 345893 80291 74 3 0x100092 bpf pflogd 80291 210413 1 0 3 0x80 netio pflogd 92769 484381 59553 73 2 0x100090 syslogd 59553 396089 1 0 3 0x100082 netio syslogd 95360 303867 1 77 3 0x100090 poll dhclient 92126 30830 1 0 3 0x80 poll dhclient 80432 475085 0 0 2 0x14200 zerothread 9835 57137 0 0 3 0x14200 aiodoned aiodoned 22537 401547 0 0 3 0x14200 syncer update 65260 148967 0 0 3 0x14200 cleaner cleaner 29185 338980 0 0 7 0x14200 reaper 31913 353723 0 0 3 0x14200 pgdaemon pagedaemon 40503 307421 0 0 3 0x14200 bored crynlk 48392 386102 0 0 3 0x14200 bored crypto 58575 346061 0 0 3 0x40014200 acpi0 acpi0 29877 241428 0 0 3 0x40014200 idle1 13950 463896 0 0 3 0x14200 bored softnet 725 42596 0 0 3 0x14200 bored systqmp 35795 501089 0 0 3 0x14200 bored systq 37963 326824 0 0 3 0x40014200 bored softclock 82090 105200 0 0 3 0x40014200 idle0 76873 508721 0 0 3 0x14200 bored smr 1 211380 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 (0xffff800020b8c0d8) #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 97477 (syz-executor.1) thread 0xffff800020b9ae28 (22203) exclusive rrwlock inode r = 0 (0xfffffd80663c6c58) #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_mknod+0x4e sys/ufs/ufs/ufs_vnops.c:172 #8 VOP_MKNOD+0x6a sys/kern/vfs_vops.c:134 #9 domknodat+0x319 sys/kern/vfs_syscalls.c:1546 #10 syscall+0x552 mi_syscall sys/sys/syscall_mi.h:99 [inline] #10 syscall+0x552 sys/arch/amd64/amd64/trap.c:574 #11 Xsyscall+0x128 exclusive rrwlock inode r = 0 (0xfffffd80663c6a38) #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 domknodat+0x92 sys/kern/vfs_syscalls.c:1498 #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{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim Kern Lim devbuf 9481 6394K 7037K 78643K 10851 0 0 pcb 25 9K 10K 78643K 149 0 0 rtable 108 4K 4K 78643K 216 0 0 ifaddr 46 11K 11K 78643K 52 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 4K 78643K 1475 0 0 iov 0 0K 24K 78643K 15 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1210 76K 76K 78643K 1324 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 5 0 0 VM map 2 1K 1K 78643K 2 0 0 sem 12 0K 1K 78643K 22 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1808 196K 290K 78643K 12628 0 0 file desc 5 13K 25K 78643K 181 0 0 sigio 0 0K 0K 78643K 4 0 0 proc 53 50K 83K 78643K 397 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 13 0 0 in_multi 33 2K 2K 78643K 47 0 0 ether_multi 1 0K 0K 78643K 3 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 42 185K 185K 78643K 42 0 0 exec 0 0K 1K 78643K 223 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 88 20K 21K 78643K 1483 0 0 UVM aobj 7 2K 2K 78643K 8 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 12 0 0 NDP 8 0K 0K 78643K 13 0 0 temp 108 2722K 2788K 78643K 3746 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 280 109 0 102 1 0 1 1 0 8 0 plimitpl 152 18 0 10 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtentry 112 45 0 1 2 0 2 2 0 8 0 syncache 264 4 0 4 1 1 0 1 0 8 0 tcpqe 32 14 0 14 1 1 0 1 0 8 0 tcpcb 544 40 0 36 1 0 1 1 0 8 0 nd6 48 6 0 0 1 0 1 1 0 8 0 ppxss 1128 1 0 1 1 0 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 12 0 2 1 0 1 1 0 8 0 pfstkey 112 12 0 2 1 0 1 1 0 8 0 pfstate 328 12 0 2 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 44 0 4 1 0 1 1 0 8 0 semupl 112 3 0 3 1 0 1 1 0 8 1 semapl 112 16 0 6 1 0 1 1 0 8 0 shmpl 112 6 0 1 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 1682 0 254 47 0 47 47 0 8 0 ffsino 272 1682 0 254 96 0 96 96 0 8 0 nchpl 144 2119 0 479 61 0 61 61 0 8 0 uvmvnodes 72 1790 0 0 33 0 33 33 0 8 0 vnodes 200 1790 0 0 95 0 95 95 0 8 0 namei 1024 5683 0 5682 3 2 1 1 0 8 0 percpumem 16 30 0 0 1 0 1 1 0 8 0 scsiplug 64 1 0 1 1 0 1 1 0 8 1 scxspl 192 5566 0 5565 9 8 1 6 0 8 0 sigapl 432 381 0 365 3 0 3 3 0 8 1 futexpl 56 1863 0 1863 1 0 1 1 0 8 1 knotepl 112 88 0 69 1 0 1 1 0 8 0 kqueuepl 104 40 0 38 1 0 1 1 0 8 0 pipepl 112 260 0 241 2 1 1 1 0 8 0 fdescpl 488 382 0 366 3 0 3 3 0 8 0 filepl 152 1999 0 1900 6 1 5 5 0 8 1 lockfpl 104 29 0 29 2 1 1 1 0 8 1 lockfspl 48 14 0 14 2 1 1 1 0 8 1 sessionpl 112 18 0 7 1 0 1 1 0 8 0 pgrppl 48 18 0 7 1 0 1 1 0 8 0 ucredpl 96 275 0 266 1 0 1 1 0 8 0 zombiepl 144 366 0 365 3 2 1 1 0 8 0 processpl 888 397 0 365 4 0 4 4 0 8 0 procpl 600 724 0 681 4 0 4 4 0 8 0 sockpl 384 229 0 210 4 1 3 3 0 8 1 mcl64k 65536 11 0 0 2 0 2 2 0 8 0 mcl16k 16384 1 0 0 1 0 1 1 0 8 0 mcl12k 12288 2 0 0 1 0 1 1 0 8 0 mcl4k 4096 4 0 0 1 0 1 1 0 8 0 mcl2k 2048 125 0 0 15 0 15 15 0 8 0 mtagpl 80 1 0 0 1 0 1 1 0 8 0 mbufpl 256 168 0 0 9 0 9 9 0 8 0 bufpl 256 6056 0 1188 305 0 305 305 0 8 0 anonpl 16 41716 0 32313 42 2 40 40 0 125 0 amapchunkpl 152 1810 0 1716 7 1 6 6 0 158 1 amappl16 192 1373 0 864 27 0 27 27 0 8 1 amappl14 176 114 0 109 2 1 1 1 0 8 0 amappl12 160 13 0 11 1 0 1 1 0 8 0 amappl11 152 56 0 38 1 0 1 1 0 8 0 amappl10 144 76 0 73 1 0 1 1 0 8 0 amappl9 136 591 0 588 1 0 1 1 0 8 0 amappl8 128 143 0 130 1 0 1 1 0 8 0 amappl7 120 34 0 31 1 0 1 1 0 8 0 amappl6 112 59 0 51 1 0 1 1 0 8 0 amappl5 104 129 0 116 1 0 1 1 0 8 0 amappl4 96 546 0 522 1 0 1 1 0 8 0 amappl3 88 262 0 249 1 0 1 1 0 8 0 amappl2 80 2143 0 2065 4 2 2 3 0 8 0 amappl1 72 17778 0 17325 26 15 11 20 0 8 1 amappl 80 980 0 942 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 7 0 1 1 0 1 1 0 8 0 uaddrrnd 24 382 0 365 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 382 0 365 1 0 1 1 0 8 0 vmmpekpl 168 7117 0 7087 2 0 2 2 0 8 0 vmmpepl 168 49043 0 47412 109 23 86 86 0 357 15 vmsppl 360 381 0 365 2 0 2 2 0 8 0 pdppl 4096 772 0 730 6 0 6 6 0 8 0 pvpl 32 153454 0 140830 124 14 110 110 0 265 8 pmappl 232 381 0 365 2 0 2 2 0 8 1 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 459 0 5 13 0 13 13 0 8 0