login: witness: acquiring duplicate lock of same type: "&sc->sc_lock" 1st wsmuxlk @ /syzkaller/managers/multicore/kernel/sys/dev/wscons/wsmux.c:629 2nd wsmuxlk @ /syzkaller/managers/multicore/kernel/sys/dev/wscons/wsmux.c:245 Starting stack trace... witness_checkorder(ffff8000021a9ed0,1,ffffffff81f33463,f5,0) at witness_checkorder+0xe14 witness_debugger sys/kern/subr_witness.c:2650 [inline] witness_checkorder(ffff8000021a9ed0,1,ffffffff81f33463,f5,0) at witness_checkorder+0xe14 sys/kern/subr_witness.c:926 _rw_enter_read(ffff8000021a9ec0,ffffffff81f33463,f5) at _rw_enter_read+0x80 sys/kern/kern_rwlock.c:102 wsmux_mux_open(ffff8000021a9e00,ffff8000021a9d50) at wsmux_mux_open+0x82 wsmux_do_open sys/dev/wscons/wsmux.c:246 [inline] wsmux_mux_open(ffff8000021a9e00,ffff8000021a9d50) at wsmux_mux_open+0x82 sys/dev/wscons/wsmux.c:228 wsmux_attach_sc(ffff8000021a9d00,ffff8000021a9e00) at wsmux_attach_sc+0x180 sys/dev/wscons/wsmux.c:670 VOP_IOCTL(fffffd80670b86b0,80085761,ffff800020bf59f0,f,fffffd807f7c7a80,ffff800020b42270) at VOP_IOCTL+0x9a sys/kern/vfs_vops.c:290 vn_ioctl(fffffd806fc9f428,80085761,ffff800020bf59f0,ffff800020b42270) at vn_ioctl+0xc9 sys/kern/vfs_vnops.c:512 sys_ioctl(ffff800020b42270,ffff800020bf5b38,ffff800020bf5b20) at sys_ioctl+0x646 syscall(ffff800020bf5bd0) at syscall+0x5ac mi_syscall sys/sys/syscall_mi.h:99 [inline] syscall(ffff800020bf5bd0) at syscall+0x5ac sys/arch/amd64/amd64/trap.c:574 Xsyscall(6,0,ffffffffffffff86,0,3,4173ed70010) at Xsyscall+0x128 end of kernel end trace frame: 0x419d4f92600, count: 248 End of stack trace. 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:399 witness_checkorder(ffff8000021a9ed0,1,ffffffff81f33463,f5,0) at witness_checkorder+0xe19 witness_debugger sys/kern/subr_witness.c:2650 [inline] witness_checkorder(ffff8000021a9ed0,1,ffffffff81f33463,f5,0) at witness_checkorder+0xe19 sys/kern/subr_witness.c:926 _rw_enter_read(ffff8000021a9ec0,ffffffff81f33463,f5) at _rw_enter_read+0x80 sys/kern/kern_rwlock.c:102 wsmux_mux_open(ffff8000021a9e00,ffff8000021a9d50) at wsmux_mux_open+0x82 wsmux_do_open sys/dev/wscons/wsmux.c:246 [inline] wsmux_mux_open(ffff8000021a9e00,ffff8000021a9d50) at wsmux_mux_open+0x82 sys/dev/wscons/wsmux.c:228 wsmux_attach_sc(ffff8000021a9d00,ffff8000021a9e00) at wsmux_attach_sc+0x180 sys/dev/wscons/wsmux.c:670 VOP_IOCTL(fffffd80670b86b0,80085761,ffff800020bf59f0,f,fffffd807f7c7a80,ffff800020b42270) at VOP_IOCTL+0x9a sys/kern/vfs_vops.c:290 vn_ioctl(fffffd806fc9f428,80085761,ffff800020bf59f0,ffff800020b42270) at vn_ioctl+0xc9 sys/kern/vfs_vnops.c:512 sys_ioctl(ffff800020b42270,ffff800020bf5b38,ffff800020bf5b20) at sys_ioctl+0x646 syscall(ffff800020bf5bd0) at syscall+0x5ac mi_syscall sys/sys/syscall_mi.h:99 [inline] syscall(ffff800020bf5bd0) at syscall+0x5ac sys/arch/amd64/amd64/trap.c:574 Xsyscall(6,0,ffffffffffffff86,0,3,4173ed70010) at Xsyscall+0x128 end of kernel end trace frame: 0x419d4f92600, count: -10 ddb{1}> show registers rdi 0 rsi 0x3ffff acpi_pdirpa+0x2be67 rbp 0xffff800020bf5620 rbx 0x3 rdx 0x40000 acpi_pdirpa+0x2be68 rcx 0xffff800001fa9000 rax 0xffff800001950740 r8 0xffffffff818cb2f3 kprintf+0x183 r9 0x1 r10 0x25 r11 0x1287a8c0bcda96cf r12 0xffffffff81f33463 substchar+0x92c4 r13 0xf5 r14 0xffffffff81f22d40 cmd680_setup_channel.udma_tbl+0x3c0b r15 0xffffffff81f33463 substchar+0x92c4 rip 0xffffffff811a46a8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020bf5610 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor.1) pid=284597 stat=onproc flags process=0 proc=4000000 pri=74, usrpri=74, nice=20 forw=0xffffffffffffffff, list=0xffff800020b42978,0xffff800020b42be0 process=0xffff800020b0b700 user=0xffff800020bf0000, vmspace=0xfffffd807effe2d0 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 94332 448361 94302 0 2 0 syz-executor.0 59005 348122 1322 0 7 0 syz-executor.1 *59005 284597 1322 0 7 0x4000000 syz-executor.1 93112 389857 1 0 3 0x100083 ttyin getty 94302 291229 81228 0 3 0x82 nanosleep syz-executor.0 1322 141881 81228 0 3 0x82 nanosleep syz-executor.1 89415 157778 0 0 3 0x14200 bored sosplice 81228 496193 55335 0 3 0x82 thrsleep syz-fuzzer 81228 22475 55335 0 3 0x4000082 thrsleep syz-fuzzer 81228 125470 55335 0 3 0x4000082 thrsleep syz-fuzzer 81228 466559 55335 0 3 0x4000082 thrsleep syz-fuzzer 81228 359042 55335 0 3 0x4000082 thrsleep syz-fuzzer 81228 268076 55335 0 3 0x4000082 thrsleep syz-fuzzer 81228 248404 55335 0 3 0x4000082 thrsleep syz-fuzzer 81228 466328 55335 0 3 0x4000082 kqread syz-fuzzer 81228 469565 55335 0 3 0x4000082 thrsleep syz-fuzzer 81228 455833 55335 0 3 0x4000082 thrsleep syz-fuzzer 55335 199242 64886 0 3 0x10008a pause ksh 64886 361820 49769 0 3 0x92 select sshd 49769 309487 1 0 3 0x80 select sshd 65852 305944 26721 73 2 0x100090 syslogd 26721 77598 1 0 3 0x100082 netio syslogd 53416 920 1 77 3 0x100090 poll dhclient 16958 280120 1 0 3 0x80 poll dhclient 18819 149658 0 0 3 0x14200 pgzero zerothread 17697 211078 0 0 3 0x14200 aiodoned aiodoned 94106 99017 0 0 3 0x14200 syncer update 91799 389768 0 0 3 0x14200 cleaner cleaner 6596 32797 0 0 3 0x14200 reaper reaper 48138 199210 0 0 3 0x14200 pgdaemon pagedaemon 23377 179127 0 0 3 0x14200 bored crynlk 27569 391876 0 0 3 0x14200 bored crypto 38064 234403 0 0 3 0x40014200 acpi0 acpi0 1942 369782 0 0 3 0x40014200 idle1 52408 458786 0 0 3 0x14200 bored softnet 78510 121126 0 0 3 0x14200 bored systqmp 85916 298945 0 0 3 0x14200 bored systq 13300 469538 0 0 3 0x40014200 bored softclock 45795 201863 0 0 3 0x40014200 idle0 1 438131 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 59005 (syz-executor.1) thread 0xffff800020b42270 (284597) exclusive rwlock wsmuxlk r = 0 (0xffff8000021a9dd0) locked @ /syzkaller/managers/multicore/kernel/sys/dev/wscons/wsmux.c:629 #0 witness_lock+0x58a sys/kern/subr_witness.c:1205 #1 wsmux_attach_sc+0x48 sys/dev/wscons/wsmux.c:635 #2 VOP_IOCTL+0x9a sys/kern/vfs_vops.c:290 #3 vn_ioctl+0xc9 sys/kern/vfs_vnops.c:512 #4 sys_ioctl+0x646 #5 syscall+0x5ac mi_syscall sys/sys/syscall_mi.h:99 [inline] #5 syscall+0x5ac sys/arch/amd64/amd64/trap.c:574 #6 Xsyscall+0x128 exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82360c40) locked @ /syzkaller/managers/multicore/kernel/sys/sys/syscall_mi.h:90 #0 witness_lock+0x58a sys/kern/subr_witness.c:1205 #1 syscall+0x47f mi_syscall sys/sys/syscall_mi.h:91 [inline] #1 syscall+0x47f sys/arch/amd64/amd64/trap.c:574 #2 Xsyscall+0x128 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim Kern Lim devbuf 9537 6370K 6374K 78643K 11230 0 0 pcb 23 9K 11K 78643K 904 0 0 rtable 100 3K 4K 78643K 694 0 0 ifaddr 60 13K 14K 78643K 254 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 2K 78643K 41 0 0 iov 0 0K 20K 78643K 192 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1202 75K 76K 78643K 2516 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 36 0 0 VM map 2 1K 1K 78643K 2 0 0 sem 12 0K 0K 78643K 222 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1792 194K 288K 78643K 12592 0 0 file desc 6 17K 21K 78643K 1802 0 0 sigio 0 0K 0K 78643K 20 0 0 proc 42 38K 70K 78643K 719 0 0 subproc 64 65538K 67586K 78643K 349 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 211 0 0 in_multi 33 2K 2K 78643K 170 0 0 ether_multi 1 0K 0K 78643K 12 0 0 mrt 0 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 96 424K 424K 78643K 96 0 0 exec 0 0K 1K 78643K 367 0 0 pfkey data 0 0K 0K 78643K 2 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 96 21K 30K 78643K 6679 0 0 UVM aobj 103 3K 4K 78643K 118 0 0 memdesc 1 4K 4K 78643K 1 0 0 crypto data 1 1K 1K 78643K 1 0 0 ip6_options 0 0K 1K 78643K 51 0 0 NDP 13 0K 0K 78643K 81 0 0 temp 177 2367K 2433K 78643K 8113 0 0 kqueue 0 0K 0K 78643K 12 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 12 0 8 1 0 1 1 0 8 0 inpcbpl 280 832 0 825 1 0 1 1 0 8 0 plimitpl 152 52 0 45 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtentry 112 113 0 73 2 0 2 2 0 8 0 syncache 264 4 0 4 1 1 0 1 0 8 0 tcpcb 544 292 0 288 1 0 1 1 0 8 0 nd6 48 20 0 16 1 0 1 1 0 8 0 ppxss 1128 28 0 28 7 6 1 1 0 8 1 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 522 0 334 12 0 12 12 0 8 0 art_table 32 523 0 334 2 0 2 2 0 8 0 art_node 16 112 0 78 1 0 1 1 0 8 0 sysvmsgpl 40 6 0 2 1 0 1 1 0 8 0 semapl 112 220 0 210 1 0 1 1 0 8 0 shmpl 112 116 0 15 3 0 3 3 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 4937 0 3521 46 0 46 46 0 8 0 ffsino 272 4937 0 3521 95 0 95 95 0 8 0 nchpl 144 7655 0 6044 61 0 61 61 0 8 0 uvmvnodes 72 5297 0 0 97 0 97 97 0 8 0 vnodes 200 5297 0 0 279 0 279 279 0 8 0 namei 1024 23041 0 23041 2 1 1 1 0 8 1 percpumem 16 30 0 0 1 0 1 1 0 8 0 scsiplug 64 4 0 4 3 3 0 1 0 8 0 scxspl 192 19909 0 19909 13 12 1 6 0 8 1 sigapl 432 1950 0 1936 2 0 2 2 0 8 0 futexpl 56 19974 0 19974 1 0 1 1 0 8 1 knotepl 112 716 0 689 3 2 1 2 0 8 0 kqueuepl 104 627 0 625 1 0 1 1 0 8 0 pipepl 112 1284 0 1265 4 2 2 2 0 8 1 fdescpl 488 1951 0 1936 3 1 2 3 0 8 0 filepl 152 12147 0 12052 8 3 5 6 0 8 1 lockfpl 104 563 0 563 2 1 1 1 0 8 1 lockfspl 32 674 0 674 2 1 1 1 0 8 1 sessionpl 112 29 0 19 1 0 1 1 0 8 0 pgrppl 48 59 0 49 1 0 1 1 0 8 0 ucredpl 96 3478 0 3471 1 0 1 1 0 8 0 zombiepl 144 1936 0 1936 2 1 1 1 0 8 1 processpl 840 1966 0 1936 4 0 4 4 0 8 0 procpl 600 5869 0 5829 4 0 4 4 0 8 0 srpgc 64 48 0 48 3 3 0 1 0 8 0 sosppl 128 28 0 28 6 6 0 1 0 8 0 sockpl 384 1637 0 1620 4 1 3 4 0 8 1 mcl64k 65536 306 0 0 35 4 31 33 0 8 0 mcl16k 16384 2 0 0 1 0 1 1 0 8 0 mcl12k 12288 16 0 0 2 0 2 2 0 8 0 mcl9k 9216 8 0 0 1 0 1 1 0 8 0 mcl8k 8192 7 0 0 1 0 1 1 0 8 0 mcl4k 4096 7 0 0 1 0 1 1 0 8 0 mcl2k2 2112 5 0 0 1 0 1 1 0 8 0 mcl2k 2048 110 0 0 13 0 13 13 0 8 0 mtagpl 80 4 0 0 1 0 1 1 0 8 0 mbufpl 256 400 0 0 20 0 20 20 0 8 0 bufpl 256 8492 0 1520 436 0 436 436 0 8 0 anonpl 16 200862 0 192975 98 53 45 49 0 125 10 amapchunkpl 152 11545 0 11457 25 20 5 9 0 158 0 amappl16 192 10596 0 10168 87 56 31 34 0 8 8 amappl15 184 158 0 156 1 0 1 1 0 8 0 amappl14 176 172 0 167 2 1 1 1 0 8 0 amappl13 168 554 0 551 1 0 1 1 0 8 0 amappl12 160 12 0 11 1 0 1 1 0 8 0 amappl11 152 760 0 751 1 0 1 1 0 8 0 amappl10 144 67 0 64 2 1 1 1 0 8 0 amappl9 136 915 0 912 1 0 1 1 0 8 0 amappl8 128 197 0 168 1 0 1 1 0 8 0 amappl7 120 64 0 56 1 0 1 1 0 8 0 amappl6 112 215 0 204 1 0 1 1 0 8 0 amappl5 104 143 0 132 1 0 1 1 0 8 0 amappl4 96 1319 0 1293 2 1 1 2 0 8 0 amappl3 88 213 0 208 1 0 1 1 0 8 0 amappl2 80 17838 0 17784 2 0 2 2 0 8 0 amappl1 72 51012 0 50594 25 16 9 19 0 8 0 amappl 72 6133 0 6099 1 0 1 1 0 75 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 64 117 0 15 2 0 2 2 0 8 0 uaddrrnd 24 1951 0 1936 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 1951 0 1936 1 0 1 1 0 8 0 vmmpekpl 168 19872 0 19847 2 0 2 2 0 8 0 vmmpepl 168 211611 0 210189 123 54 69 75 0 357 4 vmsppl 360 1950 0 1936 2 0 2 2 0 8 0 pdppl 4096 3910 0 3872 6 1 5 6 0 8 0 pvpl 32 546567 0 535632 204 87 117 127 0 265 25 pmappl 224 1950 0 1936 1 0 1 1 0 8 0 extentpl 40 39 0 25 1 0 1 1 0 8 0 phpool 112 629 0 8 18 0 18 18 0 8 0