1st 0xfffffd807f00d5b8 vmmaplk (&map->lock) @ /syzkaller/managers/multicore/kernel/sys/uvm/uvm_fault.c:1442 2nd 0xfffffd807d8d84e8 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+0x6d8 #1 _rw_enter+0xbf #2 vm_map_lock_ln+0x14e #3 uvm_map+0x2e2 #4 km_alloc+0x19a #5 pool_multi_alloc_ni+0xe4 #6 pool_p_alloc+0x70 #7 pool_do_get+0x127 #8 pool_get+0x104 #9 ufsdirhash_build+0x40b #10 ufs_lookup+0x2a5 #11 VOP_LOOKUP+0x63 #12 vfs_lookup+0x552 #13 namei+0x4af #14 start_init+0xd6 lock order "&map->lock"(rwlock) -> "&ip->i_lock"(rrwlock) first seen at: #0 witness_checkorder+0x6d8 #1 _rw_enter+0xbf #2 _rrw_enter+0x5c #3 VOP_LOCK+0x55 #4 vn_lock+0x6e #5 uvn_io+0x2ca #6 uvn_get+0x206 #7 uvm_fault+0x12c1 #8 uvm_fault_wire+0x70 #9 uvm_map_pageable_wire+0x2fd #10 uvm_map_protect+0x610 #11 syscall+0x5a0 #12 Xsyscall+0x128 Stopped at db_enter+0x18: addq $0x8,%rsp ddb{0}> ddb{0}> set $lines = 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:399 witness_checkorder(53f85e9b3073fdbd,81,fffffd807d8d84d8,fffffd807d8d84d8,0) at witness_checkorder+0x12f9 witness_debugger sys/kern/subr_witness.c:2543 [inline] witness_checkorder(53f85e9b3073fdbd,81,fffffd807d8d84d8,fffffd807d8d84d8,0) at witness_checkorder+0x12f9 sys/kern/subr_witness.c:1089 _rw_enter(67c6381dd0cd3b9e,60b,fffffd807d8d84d8,ffffffff81ed5429) at _rw_enter+0xbf _rrw_enter(174d885639dafea7,fffffd806ab484d8,ffffffff819017a0,800) at _rrw_enter+0x5c sys/kern/kern_rwlock.c:410 VOP_LOCK(83aaf631affb1a77,fffffd806ab484d8) at VOP_LOCK+0x55 sys/kern/vfs_vops.c:598 vn_lock(1a2752fb9b265c77,1000) at vn_lock+0x6e sys/kern/vfs_vnops.c:549 uvn_io(15fa9d86a0c74d79,0,0,fffffd807ea1b678,0) at uvn_io+0x2ca sys/uvm/uvm_vnode.c:1188 uvn_get(a2852d69d69db303,ffffffff8136c1a0,fffffd807ea1b678,fffffd806cedaea8,0,4) at uvn_get+0x206 sys/uvm/uvm_vnode.c:1048 uvm_fault(7e153c5496e51d1a,20ffd000,0,4) at uvm_fault+0x12c1 sys/uvm/uvm_fault.c:1023 uvm_fault_wire(a2484f322346f372,4,20ffd000,fffffd806cedaea8) at uvm_fault_wire+0x70 sys/uvm/uvm_fault.c:1293 uvm_map_pageable_wire(147766264ab614e,fffffd806cedaea8,20ffd000,20ffb000,0,4) at uvm_map_pageable_wire+0x2fd sys/uvm/uvm_map.c:2258 uvm_map_protect(53f85e9b30ab6e02,0,ffff800020bbb530,a0d24737f68,0) at uvm_map_protect+0x610 sys/uvm/uvm_map.c:3294 syscall(9aa28a24edcf524f) at syscall+0x5a0 mi_syscall sys/sys/syscall_mi.h:99 [inline] syscall(9aa28a24edcf524f) at syscall+0x5a0 sys/arch/amd64/amd64/trap.c:583 Xsyscall(6,0,ffffffffffffffa4,0,3,a0aac565010) at Xsyscall+0x128 end of kernel end trace frame: 0xa0d24737ff0, count: -14 ddb{0}> show registers rdi 0x3 rsi 0x3ffff acpi_pdirpa+0x2be67 rbp 0xffff800020c7a870 rbx 0x3 rdx 0x40000 acpi_pdirpa+0x2be68 rcx 0xffff800000946000 rax 0xffff800000940700 r8 0xffffffff81bca74f witness_checkorder+0x12cf r9 0x5 r10 0x9c31b6b6eafd1233 r11 0xddd9a773f0cade60 r12 0xfffffd80025ccc30 r13 0xffffffff81eba9a8 cmd0646_9_tim_udma+0xd171 r14 0xffffffff822c1430 w_lodata+0x4c0e0 r15 0xffffffff822cb040 w_lodata+0x55cf0 rip 0xffffffff817711a8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020c7a860 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor0) pid=105436 stat=onproc flags process=0 proc=4000000 pri=86, usrpri=86, nice=20 forw=0xffffffffffffffff, list=0xffff800020bba720,0xffffffff822db680 process=0xffff800020b94010 user=0xffff800020c76000, vmspace=0xfffffd807f00d5a0 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 47270 306248 79081 0 2 0 syz-executor0 *47270 105436 79081 0 7 0x4000000 syz-executor0 72805 393607 0 0 3 0x14200 bored sosplice 31887 191260 67842 0 3 0x2 biowait syz-executor1 79081 271672 67842 0 3 0x82 nanosleep syz-executor0 67842 350260 37395 0 3 0x82 thrsleep syz-fuzzer 67842 15926 37395 0 3 0x4000082 nanosleep syz-fuzzer 67842 314183 37395 0 3 0x4000082 thrsleep syz-fuzzer 67842 405854 37395 0 3 0x4000082 thrsleep syz-fuzzer 67842 246807 37395 0 3 0x4000082 thrsleep syz-fuzzer 67842 42458 37395 0 3 0x4000082 thrsleep syz-fuzzer 67842 32455 37395 0 3 0x4000082 thrsleep syz-fuzzer 67842 106680 37395 0 3 0x4000082 thrsleep syz-fuzzer 67842 166490 37395 0 3 0x4000082 thrsleep syz-fuzzer 67842 37680 37395 0 3 0x4000082 kqread syz-fuzzer 37395 125361 18415 0 3 0x10008a pause ksh 18415 160418 12545 0 3 0x92 select sshd 6684 205828 1 0 3 0x100083 ttyin getty 12545 223000 1 0 3 0x80 select sshd 22672 306300 45491 73 7 0x100090 syslogd 45491 152108 1 0 3 0x100082 netio syslogd 35523 338513 1 77 3 0x100090 poll dhclient 29271 154909 1 0 3 0x80 poll dhclient 66413 121101 0 0 3 0x14200 pgzero zerothread 98531 152248 0 0 3 0x14200 aiodoned aiodoned 95796 71544 0 0 3 0x14200 syncer update 46690 194988 0 0 3 0x14200 cleaner cleaner 34793 353676 0 0 3 0x14200 reaper reaper 41497 312079 0 0 3 0x14200 pgdaemon pagedaemon 87232 252079 0 0 3 0x14200 bored crynlk 42340 312504 0 0 3 0x14200 bored crypto 87015 234912 0 0 3 0x40014200 acpi0 acpi0 61185 139251 0 0 3 0x40014200 idle1 80416 115433 0 0 3 0x14200 bored softnet 11067 187473 0 0 3 0x14200 bored systqmp 29726 476966 0 0 3 0x14200 bored systq 60894 329185 0 0 3 0x40014200 bored softclock 2016 470649 0 0 3 0x40014200 idle0 1 499208 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper