login: witness: lock order reversal: 1st 0xffff800020afb598 &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+0x3f sys/dev/kcov.c:111 #7 mtx_leave+0x97 sys/kern/kern_lock.c:360 #8 sched_exit+0x112 sys/kern/kern_sched.c:225 #9 exit1+0x8bf sys/kern/kern_exit.c:349 #10 sys_exit+0x17 sys/kern/kern_exit.c:94 #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 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(ffff800020b84bc8) at schedclock+0x99 sys/kern/sched_bsd.c:547 hardclock(ffff800020bc3b70) 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(9,10,0,0,ffffffff821fc960,ffff800020ab0ff0) at Xresume_lapic_ltimer+0x26 __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x3f sys/dev/kcov.c:111 mtx_leave(ffff800020afb588) at mtx_leave+0x97 sys/kern/kern_lock.c:360 sched_exit(ffff800020b84bc8) at sched_exit+0x112 sys/kern/kern_sched.c:225 exit1(ffff800020b84bc8,0,1) at exit1+0x8bf sys/kern/kern_exit.c:349 sys_exit(ffff800020b84bc8,ffff800020bc3e40,ffff800020bc3eb0) at sys_exit+0x17 sys/kern/kern_exit.c:94 syscall(ffff800020bc3f20) at syscall+0x552 mi_syscall sys/sys/syscall_mi.h:99 [inline] syscall(ffff800020bc3f20) at syscall+0x552 sys/arch/amd64/amd64/trap.c:574 Xsyscall(6,1,b37,1,431bde82d7b634db,0) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffc1e30, count: -14 ddb{1}> show registers rdi 0x3 rsi 0xffffffff821fc9e0 __sancov_gen_cov_switch_values.122 rbp 0xffff800020bc3970 rbx 0x3 rdx 0x8b rcx 0x3 rax 0x3 r8 0xffffffff818c8c95 witness_checkorder+0xfd5 r9 0x5 r10 0x876747a7c1d9b7 r11 0xf2b5b9c07cb905cc r12 0xfffffd8002661340 r13 0xc r14 0xffffffff82338720 w_lodata+0x4d4d0 r15 0xffffffff82342280 w_lodata+0x57030 rip 0xffffffff81a42468 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020bc3960 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor9206) pid=9778 stat=dead flags process=1008 proc=2000 pri=50, usrpri=64, nice=20 forw=0xffffffffffffffff, list=0xffffffffffffffff,0xffffffffffffffff process=0xffff800020afb4d8 user=0xffff800020bbe000, vmspace=0xfffffd806e7c7170 estcpu=36, cpticks=2, pctcpu=0.0 user=0, sys=1, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 27229 1254 31685 0 3 0x82 nanosleep syz-executor9206 31685 150067 81105 0 3 0x10008a pause ksh 81105 390242 5389 0 3 0x92 select sshd 33145 418147 1 0 3 0x100083 ttyin getty 5389 116262 1 0 3 0x80 select sshd 28812 268777 95944 74 3 0x100092 bpf pflogd 95944 479827 1 0 3 0x80 netio pflogd 96392 280797 22516 73 7 0x100090 syslogd 22516 254463 1 0 3 0x100082 netio syslogd 29178 172402 1 77 3 0x100090 poll dhclient 51280 283180 1 0 3 0x80 poll dhclient 77592 408067 0 0 3 0x14200 pgzero zerothread 62066 183870 0 0 3 0x14200 aiodoned aiodoned 44446 421169 0 0 3 0x14200 syncer update 9041 161261 0 0 3 0x14200 cleaner cleaner 25947 196602 0 0 2 0x14200 reaper 79323 312361 0 0 3 0x14200 pgdaemon pagedaemon 96649 55405 0 0 3 0x14200 bored crynlk 83416 371981 0 0 3 0x14200 bored crypto 11699 263571 0 0 3 0x40014200 acpi0 acpi0 55336 262720 0 0 3 0x40014200 idle1 82577 46158 0 0 3 0x14200 bored softnet 29625 344390 0 0 3 0x14200 bored systqmp 5242 412546 0 0 3 0x14200 bored systq 14886 266583 0 0 3 0x40014200 bored softclock 98735 497455 0 0 3 0x40014200 idle0 88408 242489 0 0 3 0x14200 bored smr 1 38117 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 (0xffff800020afb598) #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 sched_exit+0xa5 sys/kern/kern_sched.c:224 #4 exit1+0x8bf sys/kern/kern_exit.c:349 #5 sys_exit+0x17 sys/kern/kern_exit.c:94 #6 syscall+0x552 mi_syscall sys/sys/syscall_mi.h:99 [inline] #6 syscall+0x552 sys/arch/amd64/amd64/trap.c:574 #7 Xsyscall+0x128 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim Kern Lim devbuf 9450 6382K 6383K 78643K 10537 0 0 pcb 25 9K 9K 78643K 57 0 0 rtable 61 2K 2K 78643K 125 0 0 ifaddr 25 7K 7K 78643K 26 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 4K 78643K 1467 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1175 74K 74K 78643K 1180 0 0 UFS quota 1 32K 32K 78643K 1 0 0 UFS mount 5 36K 36K 78643K 5 0 0 shm 2 1K 1K 78643K 2 0 0 VM map 2 1K 1K 78643K 2 0 0 sem 2 0K 0K 78643K 2 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1808 196K 290K 78643K 12628 0 0 file desc 1 0K 0K 78643K 1 0 0 proc 52 50K 58K 78643K 279 0 0 NFS srvsock 1 0K 0K 78643K 1 0 0 NFS daemon 1 16K 16K 78643K 1 0 0 in_multi 11 0K 0K 78643K 11 0 0 ether_multi 1 0K 0K 78643K 1 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 18 79K 79K 78643K 18 0 0 exec 0 0K 1K 78643K 179 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 62 3K 3K 78643K 6563 0 0 UVM aobj 2 2K 2K 78643K 2 0 0 memdesc 1 4K 4K 78643K 1 0 0 crypto data 1 1K 1K 78643K 1 0 0 NDP 4 0K 0K 78643K 4 0 0 temp 39 2716K 2780K 78643K 7748 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 2 0 0 1 0 1 1 0 8 0 inpcbpl 280 29 0 23 1 0 1 1 0 8 0 plimitpl 152 14 0 8 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtentry 112 23 0 1 1 0 1 1 0 8 0 syncache 264 5 0 5 2 2 0 1 0 8 0 tcpcb 544 8 0 5 1 0 1 1 0 8 0 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 8 0 6 2 1 1 1 0 8 0 pfstkey 112 8 0 6 2 1 1 1 0 8 0 pfstate 328 8 0 6 2 1 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 96 0 0 6 0 6 6 0 8 0 art_table 32 97 0 0 1 0 1 1 0 8 0 art_node 16 22 0 2 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 4267 0 2888 45 0 45 45 0 8 0 ffsino 272 4267 0 2888 92 0 92 92 0 8 0 nchpl 144 7312 0 5775 57 0 57 57 0 8 0 uvmvnodes 72 4277 0 0 78 0 78 78 0 8 0 vnodes 200 4277 0 0 226 0 226 226 0 8 0 namei 1024 15044 0 15044 3 2 1 1 0 8 1 percpumem 16 30 0 0 1 0 1 1 0 8 0 scxspl 192 19776 0 19776 30 29 1 6 0 8 1 sigapl 432 3077 0 3065 2 0 2 2 0 8 0 futexpl 56 3016 0 3016 1 0 1 1 0 8 1 knotepl 112 5 0 0 1 0 1 1 0 8 0 kqueuepl 104 1 0 0 1 0 1 1 0 8 0 pipepl 112 134 0 127 3 2 1 1 0 8 0 fdescpl 488 3078 0 3065 3 0 3 3 0 8 0 filepl 152 3830 0 3783 2 0 2 2 0 8 0 lockfpl 104 6 0 6 1 1 0 1 0 8 0 lockfspl 48 3 0 3 1 1 0 1 0 8 0 sessionpl 112 18 0 9 1 0 1 1 0 8 0 pgrppl 48 18 0 9 1 0 1 1 0 8 0 ucredpl 96 52 0 43 1 0 1 1 0 8 0 zombiepl 144 3065 0 3064 3 2 1 1 0 8 0 processpl 888 3093 0 3064 4 0 4 4 0 8 0 procpl 600 5965 0 5935 3 0 3 3 0 8 0 sockpl 384 73 0 55 2 0 2 2 0 8 0 mcl4k 4096 3 0 0 1 0 1 1 0 8 0 mcl2k 2048 83 0 0 9 0 9 9 0 8 0 mtagpl 80 1 0 0 1 0 1 1 0 8 0 mbufpl 256 104 0 0 6 0 6 6 0 8 0 bufpl 256 5051 0 287 298 0 298 298 0 8 0 anonpl 16 150840 0 149550 9 3 6 7 0 125 0 amapchunkpl 152 9168 0 9128 2 0 2 2 0 158 0 amappl16 192 6273 0 6263 1 0 1 1 0 8 0 amappl14 176 16 0 15 3 2 1 1 0 8 0 amappl12 160 5 0 5 2 2 0 1 0 8 0 amappl11 152 49 0 31 1 0 1 1 0 8 0 amappl10 144 59 0 57 1 0 1 1 0 8 0 amappl9 136 423 0 422 1 0 1 1 0 8 0 amappl8 128 102 0 97 1 0 1 1 0 8 0 amappl7 120 21 0 19 1 0 1 1 0 8 0 amappl6 112 45 0 41 1 0 1 1 0 8 0 amappl5 104 126 0 113 1 0 1 1 0 8 0 amappl4 96 3251 0 3229 1 0 1 1 0 8 0 amappl3 88 3035 0 3022 1 0 1 1 0 8 0 amappl2 80 23807 0 23744 4 2 2 2 0 8 0 amappl1 72 70251 0 69813 16 6 10 16 0 8 0 amappl 80 6170 0 6147 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 1 0 0 1 0 1 1 0 8 0 uaddrrnd 24 3078 0 3064 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 3078 0 3064 1 0 1 1 0 8 0 vmmpekpl 168 17091 0 17070 2 0 2 2 0 8 0 vmmpepl 168 226834 0 225944 57 18 39 51 0 357 0 vmsppl 360 3077 0 3064 2 0 2 2 0 8 0 pdppl 4096 6164 0 6128 6 0 6 6 0 8 0 pvpl 32 379562 0 376447 35 9 26 28 0 265 0 pmappl 232 3077 0 3064 1 0 1 1 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 430 0 5 13 0 13 13 0 8 0