1st 0xfffffd807f00d720 vmmaplk (&map->lock) @ /syzkaller/managers/multicore/kernel/sys/uvm/uvm_fault.c:1442 2nd 0xfffffd806cf442c0 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 sys_mlockall+0x69 #11 syscall+0x5a0 #12 Xsyscall+0x128 Stopped at db_enter+0x18: addq $0x8,%rsp ddb{1}> ddb{1}> set $lines = 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(a0a146027e50c45c,81,fffffd806cf442b0,fffffd806cf442b0,0) at witness_checkorder+0x12f9 witness_debugger sys/kern/subr_witness.c:2543 [inline] witness_checkorder(a0a146027e50c45c,81,fffffd806cf442b0,fffffd806cf442b0,0) at witness_checkorder+0x12f9 sys/kern/subr_witness.c:1089 _rw_enter(f45406292c89538c,60b,fffffd806cf442b0,ffffffff81ed5429) at _rw_enter+0xbf _rrw_enter(79d4576965d04ea5,fffffd806dcd3bc0,ffffffff819017a0,0) at _rrw_enter+0x5c sys/kern/kern_rwlock.c:410 VOP_LOCK(b8c92e25ff5b95dc,fffffd806dcd3bc0) at VOP_LOCK+0x55 sys/kern/vfs_vops.c:598 vn_lock(4081bc25916f22ed,2000) at vn_lock+0x6e sys/kern/vfs_vnops.c:549 uvn_io(bb57a2ed7f1207d1,0,0,fffffd806dd22128,1000) at uvn_io+0x2ca sys/uvm/uvm_vnode.c:1188 uvn_get(186f2331b36b4aaa,ffffffff8136c1a0,fffffd806dd22128,fffffd806ae8e408,1000,3) at uvn_get+0x206 sys/uvm/uvm_vnode.c:1048 uvm_fault(dbcec99db1046bc3,1b33f20000,fffffffffffff000,3) at uvm_fault+0x12c1 sys/uvm/uvm_fault.c:1023 uvm_fault_wire(42df187b49e5919,3,1b33f20000,fffffd806ae8e408) at uvm_fault_wire+0x70 sys/uvm/uvm_fault.c:1293 uvm_map_pageable_wire(8cef4633daad354e,1,ffff800020bbbc38,47bdbcb4648,0,10f0) at uvm_map_pageable_wire+0x2fd sys/uvm/uvm_map.c:2258 sys_mlockall(991773f700aee3ee,0,ffff800020bbbc38) at sys_mlockall+0x69 sys/uvm/uvm_mmap.c:801 syscall(6aefe405d4eebde) at syscall+0x5a0 mi_syscall sys/sys/syscall_mi.h:99 [inline] syscall(6aefe405d4eebde) at syscall+0x5a0 sys/arch/amd64/amd64/trap.c:583 Xsyscall(6,0,ffffffffffffffa2,0,1,479726b1010) at Xsyscall+0x128 end of kernel end trace frame: 0x47bdbcb46d0, count: -14 ddb{1}> show registers rdi 0x3 rsi 0x3ffff acpi_pdirpa+0x2be67 rbp 0xffff800020c7ab00 rbx 0x3 rdx 0x40000 acpi_pdirpa+0x2be68 rcx 0xffff800000946000 rax 0xffff800000940f00 r8 0xffffffff81bca74f witness_checkorder+0x12cf r9 0x5 r10 0x3c00b962d07fd6e9 r11 0xd58812e486c4be09 r12 0xfffffd80025ccc30 r13 0xffffffff81eba9a8 cmd0646_9_tim_udma+0xd171 r14 0xffffffff822c68c0 w_lodata+0x51570 r15 0xffffffff822cb1a0 w_lodata+0x55e50 rip 0xffffffff817711a8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020c7aaf0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor0) pid=246484 stat=onproc flags process=0 proc=4000000 pri=51, usrpri=51, nice=20 forw=0xffffffffffffffff, list=0xffff800020bbb2d8,0xffffffff822db680 process=0xffff800020b949e8 user=0xffff800020c76000, vmspace=0xfffffd807f00d708 estcpu=1, cpticks=3, pctcpu=0.0 user=0, sys=3, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 38168 418168 2035 0 7 0 syz-executor0 *38168 246484 2035 0 7 0x4000000 syz-executor0 58851 387561 85318 0 3 0x2 biowait syz-executor1 2035 483853 85318 0 3 0x82 nanosleep syz-executor0 85318 351624 40531 0 3 0x82 thrsleep syz-fuzzer 85318 187600 40531 0 3 0x4000082 nanosleep syz-fuzzer 85318 341079 40531 0 3 0x4000082 thrsleep syz-fuzzer 85318 367190 40531 0 3 0x4000082 thrsleep syz-fuzzer 85318 334293 40531 0 3 0x4000082 kqread syz-fuzzer 85318 281483 40531 0 3 0x4000082 thrsleep syz-fuzzer 85318 249988 40531 0 3 0x4000082 thrsleep syz-fuzzer 85318 41756 40531 0 3 0x4000082 thrsleep syz-fuzzer 85318 284972 40531 0 3 0x4000082 thrsleep syz-fuzzer 85318 509661 40531 0 3 0x4000082 thrsleep syz-fuzzer 40531 334235 50122 0 3 0x10008a pause ksh 50122 180109 7323 0 3 0x92 select sshd 30018 246835 1 0 3 0x100083 ttyin getty 7323 246283 1 0 3 0x80 select sshd 59675 178227 99942 73 2 0x100090 syslogd 99942 429956 1 0 3 0x100082 netio syslogd 27706 286474 1 77 3 0x100090 poll dhclient 29446 455159 1 0 3 0x80 poll dhclient 17530 31767 0 0 2 0x14200 zerothread 7220 265299 0 0 3 0x14200 aiodoned aiodoned 18719 366203 0 0 3 0x14200 syncer update 33209 169229 0 0 3 0x14200 cleaner cleaner 91397 248533 0 0 3 0x14200 reaper reaper 56598 277457 0 0 3 0x14200 pgdaemon pagedaemon 68345 190495 0 0 3 0x14200 bored crynlk 93212 637 0 0 3 0x14200 bored crypto 82870 181114 0 0 3 0x40014200 acpi0 acpi0 44037 173931 0 0 3 0x40014200 idle1 98666 95802 0 0 3 0x14200 bored softnet 1340 126134 0 0 3 0x14200 bored systqmp 16569 329307 0 0 3 0x14200 bored systq 66103 280587 0 0 3 0x40014200 bored softclock 25889 204881 0 0 3 0x40014200 idle0 1 286052 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper