login: witness: lock order reversal: 1st 0xfffffd806e849728 vmmaplk (&map->lock) @ /syzkaller/managers/multicore/kernel/sys/uvm/uvm_fault.c:1444 2nd 0xfffffd806da7c2c0 inode (&ip->i_lock) @ /syzkaller/managers/multicore/kernel/sys/ufs/ufs/ufs_vnops.c:1547 lock order "&ip->i_lock"(rrwlock) -> "&map->lock"(rwlock) first seen at: #0 witness_checkorder+0x6cd sys/kern/subr_witness.c:902 #1 _rw_enter_read+0x80 sys/kern/kern_rwlock.c:102 #2 uvmfault_lookup+0xd9 sys/uvm/uvm_fault.c:1448 #3 uvm_fault+0x7c sys/uvm/uvm_fault.c:524 #4 pageflttrap+0x217 sys/arch/amd64/amd64/trap.c:200 #5 kerntrap+0xec sys/arch/amd64/amd64/trap.c:288 #6 alltraps_kern+0x7b #7 copyout+0x53 #8 ffs_read+0x362 sys/ufs/ffs/ffs_vnops.c:254 #9 VOP_READ+0x63 sys/kern/vfs_vops.c:247 #10 vn_read+0x1c3 sys/kern/vfs_vnops.c:365 #11 dofilereadv+0x19f sys/kern/sys_generic.c:236 #12 sys_read+0x83 sys/kern/sys_generic.c:156 #13 syscall+0x576 mi_syscall sys/sys/syscall_mi.h:99 [inline] #13 syscall+0x576 sys/arch/amd64/amd64/trap.c:574 #14 Xsyscall+0x128 lock order "&map->lock"(rwlock) -> "&ip->i_lock"(rrwlock) first seen at: #0 witness_checkorder+0x6cd sys/kern/subr_witness.c:902 #1 _rw_enter+0xc6 #2 _rrw_enter+0x60 sys/kern/kern_rwlock.c:410 #3 VOP_LOCK+0x4b sys/kern/vfs_vops.c:602 #4 vn_lock+0x6e sys/kern/vfs_vnops.c:549 #5 uvn_io+0x2c9 sys/uvm/uvm_vnode.c:1188 #6 uvn_get+0x226 sys/uvm/uvm_vnode.c:1048 #7 uvm_fault+0x1205 sys/uvm/uvm_fault.c:1023 #8 uvm_fault_wire+0x70 sys/uvm/uvm_fault.c:1295 #9 uvm_map_pageable_wire+0x31d sys/uvm/uvm_map.c:2266 #10 sys_mlock+0x18b sys/uvm/uvm_mmap.c:739 #11 syscall+0x576 mi_syscall sys/sys/syscall_mi.h:99 [inline] #11 syscall+0x576 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(fffffd806da7c2c0,9,ffffffff81f54e54,60b,0) at witness_checkorder+0x12ff witness_debugger sys/kern/subr_witness.c:2646 [inline] witness_checkorder(fffffd806da7c2c0,9,ffffffff81f54e54,60b,0) at witness_checkorder+0x12ff sys/kern/subr_witness.c:1118 _rw_enter(fffffd806da7c2b0,81,ffffffff81f54e54,60b) at _rw_enter+0xc6 _rrw_enter(fffffd806da7c2b0,81,ffffffff81f54e54,60b) at _rrw_enter+0x60 sys/kern/kern_rwlock.c:410 VOP_LOCK(fffffd806dbaf3f0,81) at VOP_LOCK+0x4b sys/kern/vfs_vops.c:602 vn_lock(fffffd806dbaf3f0,81) at vn_lock+0x6e sys/kern/vfs_vnops.c:549 uvn_io(fffffd806dd55170,ffff800020bab988,1,2,0) at uvn_io+0x2c9 sys/uvm/uvm_vnode.c:1188 uvn_get(fffffd806dd55170,0,ffff800020babbe0,ffff800020babb7c,0,1) at uvn_get+0x226 sys/uvm/uvm_vnode.c:1048 uvm_fault(fffffd806e849710,20002000,2,1) at uvm_fault+0x1205 sys/uvm/uvm_fault.c:1023 uvm_fault_wire(fffffd806e849710,20002000,20005000,1) at uvm_fault_wire+0x70 sys/uvm/uvm_fault.c:1295 uvm_map_pageable_wire(fffffd806e849710,fffffd806f7bd6d8,fffffd806ebf6eb0,0,0,0) at uvm_map_pageable_wire+0x31d sys/uvm/uvm_map.c:2266 sys_mlock(ffff800020b74e20,ffff800020babde8,ffff800020babe50) at sys_mlock+0x18b sys/uvm/uvm_mmap.c:739 syscall(ffff800020babec0) at syscall+0x576 mi_syscall sys/sys/syscall_mi.h:99 [inline] syscall(ffff800020babec0) at syscall+0x576 sys/arch/amd64/amd64/trap.c:574 Xsyscall(6,0,7f7ffffd7b48,0,1,7f7ffffd7b58) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffd7b30, count: -14 ddb{1}> show registers rdi 0x3 rsi 0xffffffff8224b6c0 __sancov_gen_cov_switch_values.127 rbp 0xffff800020bab5c0 rbx 0x3 rdx 0x8b rcx 0x3 rax 0x3 r8 0xffffffff81e4fe38 witness_checkorder+0x12d8 r9 0x5 r10 0xd250112bdcd55b8a r11 0xad810bf7020cab4c r12 0xffffffff81f54e54 cmd0646_9_tim_udma+0x20fd8 r13 0xfffffd8002675c30 r14 0xffffffff823562d0 w_lodata+0x4fb50 r15 0xfffffd800267d890 rip 0xffffffff81af9938 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020bab5b0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor9253) pid=233865 stat=onproc flags process=2 proc=0 pri=50, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff800020b752d0,0xffffffff8235f4c8 process=0xffff800020b2b078 user=0xffff800020ba6000, vmspace=0xfffffd806e849710 estcpu=0, cpticks=1, pctcpu=0.0 user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND *79219 233865 63115 0 7 0x2 syz-executor9253 63115 3332 86124 0 3 0x10008a pause ksh 86124 104505 58425 0 3 0x92 select sshd 56635 187184 1 0 3 0x100083 ttyin getty 58425 318293 1 0 3 0x80 select sshd 61734 261032 30566 74 3 0x100092 bpf pflogd 30566 218156 1 0 3 0x80 netio pflogd 60527 250457 93841 73 7 0x100090 syslogd 93841 332160 1 0 3 0x100082 netio syslogd 36112 256910 1 77 3 0x100090 poll dhclient 10576 122888 1 0 3 0x80 poll dhclient 37320 414850 0 0 3 0x14200 pgzero zerothread 48579 338159 0 0 3 0x14200 aiodoned aiodoned 47036 155691 0 0 3 0x14200 syncer update 58914 386934 0 0 3 0x14200 cleaner cleaner 94950 138229 0 0 3 0x14200 reaper reaper 21325 255382 0 0 3 0x14200 pgdaemon pagedaemon 99603 194412 0 0 3 0x14200 bored crynlk 18799 338595 0 0 3 0x14200 bored crypto 88743 200786 0 0 3 0x40014200 acpi0 acpi0 67701 501703 0 0 3 0x40014200 idle1 21396 400364 0 0 3 0x14200 bored softnet 46234 287521 0 0 3 0x14200 bored systqmp 50156 491825 0 0 3 0x14200 bored systq 90024 260261 0 0 3 0x40014200 bored softclock 58175 416814 0 0 3 0x40014200 idle0 73379 130367 0 0 3 0x14200 bored smr 1 179939 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 79219 (syz-executor9253) thread 0xffff800020b74e20 (233865) shared rwlock vmmaplk r = 0 (0xfffffd806e849728) locked @ /syzkaller/managers/multicore/kernel/sys/uvm/uvm_fault.c:1444 #0 witness_lock+0x5a4 sys/kern/subr_witness.c:1201 #1 _rw_enter+0x43c sys/kern/kern_rwlock.c:280 #2 vm_map_lock_ln+0x164 sys/uvm/uvm_map.c:5261 #3 uvm_map_pageable+0x12b sys/uvm/uvm_map.c:2362 #4 sys_mlock+0x18b sys/uvm/uvm_mmap.c:739 #5 syscall+0x576 mi_syscall sys/sys/syscall_mi.h:99 [inline] #5 syscall+0x576 sys/arch/amd64/amd64/trap.c:574 #6 Xsyscall+0x128 exclusive kernel_lock &kernel_lock r = 0 (0xffffffff823b21b8) locked @ /syzkaller/managers/multicore/kernel/sys/sys/syscall_mi.h:90 #0 witness_lock+0x5a4 sys/kern/subr_witness.c:1201 #1 syscall+0x45e mi_syscall sys/sys/syscall_mi.h:91 [inline] #1 syscall+0x45e 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 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 1167 73K 73K 78643K 1172 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 3 0K 0K 78643K 3 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 52 3K 3K 78643K 764 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 2696K 2760K 78643K 1995 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 1 0 1 1 0 8 1 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 2 1 0 1 1 0 8 0 pfstkey 112 8 0 2 1 0 1 1 0 8 0 pfstate 328 8 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 97 0 0 7 0 7 7 0 8 0 art_table 32 98 0 0 1 0 1 1 0 8 0 art_node 16 22 0 2 1 0 1 1 0 8 0 semapl 112 1 0 0 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 1391 0 17 45 0 45 45 0 8 0 ffsino 272 1391 0 17 92 0 92 92 0 8 0 nchpl 144 1564 0 32 57 0 57 57 0 8 0 uvmvnodes 72 1401 0 0 26 0 26 26 0 8 0 vnodes 200 1401 0 0 74 0 74 74 0 8 0 namei 1024 3551 0 3551 2 1 1 1 0 8 1 percpumem 16 30 0 0 1 0 1 1 0 8 0 scxspl 192 2444 0 2444 8 7 1 6 0 8 1 sigapl 432 205 0 193 2 0 2 2 0 8 0 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 2 1 1 1 0 8 0 fdescpl 488 206 0 193 3 0 3 3 0 8 0 filepl 152 962 0 914 2 0 2 2 0 8 0 lockfpl 104 6 0 6 1 1 0 1 0 8 0 lockfspl 32 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 144 193 0 193 2 1 1 1 0 8 1 processpl 840 221 0 193 4 0 4 4 0 8 0 procpl 600 221 0 193 3 0 3 3 0 8 0 sockpl 384 73 0 55 2 0 2 2 0 8 0 mcl4k 4096 5 0 0 1 0 1 1 0 8 0 mcl2k 2048 71 0 0 9 0 9 9 0 8 0 mtagpl 80 1 0 0 1 0 1 1 0 8 0 mbufpl 256 106 0 0 6 0 6 6 0 8 0 bufpl 256 2134 0 271 117 0 117 117 0 8 0 anonpl 16 19134 0 17932 8 2 6 7 0 125 1 amapchunkpl 152 552 0 515 2 0 2 2 0 158 0 amappl16 192 84 0 80 1 0 1 1 0 8 0 amappl14 176 16 0 15 2 1 1 1 0 8 0 amappl12 160 4 0 4 1 0 1 1 0 8 1 amappl11 152 40 0 22 1 0 1 1 0 8 0 amappl10 144 58 0 55 1 0 1 1 0 8 0 amappl9 136 417 0 416 1 0 1 1 0 8 0 amappl8 128 99 0 94 1 0 1 1 0 8 0 amappl7 120 19 0 18 1 0 1 1 0 8 0 amappl6 112 45 0 41 1 0 1 1 0 8 0 amappl5 104 121 0 108 1 0 1 1 0 8 0 amappl4 96 440 0 413 1 0 1 1 0 8 0 amappl3 88 106 0 101 1 0 1 1 0 8 0 amappl2 80 639 0 600 1 0 1 1 0 8 0 amappl1 72 13874 0 13458 16 6 10 16 0 8 0 amappl 72 426 0 405 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 1 0 0 1 0 1 1 0 8 0 uaddrrnd 24 206 0 193 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 206 0 193 1 0 1 1 0 8 0 vmmpekpl 168 5614 0 5593 2 0 2 2 0 8 0 vmmpepl 168 27314 0 26551 54 17 37 50 0 357 0 vmsppl 360 205 0 193 2 0 2 2 0 8 0 pdppl 4096 420 0 386 6 0 6 6 0 8 0 pvpl 32 80591 0 77673 31 3 28 28 0 265 1 pmappl 232 205 0 193 1 0 1 1 0 8 0 extentpl 40 39 0 25 1 0 1 1 0 8 0 phpool 112 249 0 4 7 0 7 7 0 8 0 ddb{1}>