1st 0xfffffd807f00db58 vmmaplk (&map->lock) @ /syzkaller/managers/multicore/kernel/sys/uvm/uvm_fault.c:1442 2nd 0xfffffd807a9132b8 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{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(1b69bfc363553f61,81,fffffd807a9132a8,fffffd807a9132a8,0) at witness_checkorder+0x12f9 witness_debugger sys/kern/subr_witness.c:2543 [inline] witness_checkorder(1b69bfc363553f61,81,fffffd807a9132a8,fffffd807a9132a8,0) at witness_checkorder+0x12f9 sys/kern/subr_witness.c:1089 _rw_enter(6d9cc3804504463f,60b,fffffd807a9132a8,ffffffff81ed5429) at _rw_enter+0xbf _rrw_enter(b28dab4bdf26112d,fffffd807b6286e8,ffffffff819017a0,0) at _rrw_enter+0x5c sys/kern/kern_rwlock.c:410 VOP_LOCK(ab846c7e5af2fd78,fffffd807b6286e8) at VOP_LOCK+0x55 sys/kern/vfs_vops.c:598 vn_lock(dad89af1a9ef0069,1000) at vn_lock+0x6e sys/kern/vfs_vnops.c:549 uvn_io(d32ef6d21686a0cd,0,0,fffffd807bf8e958,0) at uvn_io+0x2ca sys/uvm/uvm_vnode.c:1188 uvn_get(403f1e0bda966e09,ffffffff8136c1a0,fffffd807bf8e958,fffffd8007a86798,0,1) at uvn_get+0x206 sys/uvm/uvm_vnode.c:1048 uvm_fault(cc1deac4ba44ae95,21000000,0,1) at uvm_fault+0x12c1 sys/uvm/uvm_fault.c:1023 uvm_fault_wire(547f936a0e5f5773,1,21000000,fffffd8007a86798) at uvm_fault_wire+0x70 sys/uvm/uvm_fault.c:1293 uvm_map_pageable_wire(f2fd78100bffdd9a,fffffd8007a86798,21000000,20ff7000,0,4) at uvm_map_pageable_wire+0x2fd sys/uvm/uvm_map.c:2258 uvm_map_protect(1b69bfc3638dacde,0,ffff800020b92e28,ab3530f5678,0) at uvm_map_protect+0x610 sys/uvm/uvm_map.c:3294 syscall(338d2dbcde7b022d) at syscall+0x5a0 mi_syscall sys/sys/syscall_mi.h:99 [inline] syscall(338d2dbcde7b022d) at syscall+0x5a0 sys/arch/amd64/amd64/trap.c:583 Xsyscall(6,0,ffffffffffffffa4,0,3,ab102eff010) at Xsyscall+0x128 end of kernel end trace frame: 0xab3530f5700, count: -14 ddb{1}> show registers rdi 0x3 rsi 0x3ffff acpi_pdirpa+0x2be67 rbp 0xffff800020c610e0 rbx 0x3 rdx 0x40000 acpi_pdirpa+0x2be68 rcx 0xffff800002b48000 rax 0xffff800001b46c00 r8 0xffffffff81bca74f witness_checkorder+0x12cf r9 0x5 r10 0xe03d9231ed96d18d r11 0xb22666d4565bdf70 r12 0xfffffd80025ccc30 r13 0xffffffff81eba9a8 cmd0646_9_tim_udma+0xd171 r14 0xffffffff822b6bc0 w_lodata+0x41870 r15 0xffffffff822cb1a0 w_lodata+0x55e50 rip 0xffffffff817711a8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020c610d0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor1) pid=358662 stat=onproc flags process=0 proc=4000000 pri=86, usrpri=86, nice=20 forw=0xffffffffffffffff, list=0xffff800020b932d8,0xffff800020b92280 process=0xffff800020b95078 user=0xffff800020c5c000, vmspace=0xfffffd807f00db40 estcpu=36, cpticks=3, pctcpu=0.0 user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 76007 93906 68588 0 7 0 syz-executor0 76007 472141 68588 0 2 0x4000000 syz-executor0 14131 230177 85302 0 2 0 syz-executor1 *14131 358662 85302 0 7 0x4000000 syz-executor1 42605 212644 1 0 3 0x100083 ttyin getty 67218 327750 0 0 3 0x14200 bored sosplice 85302 186910 69043 0 3 0x82 nanosleep syz-executor1 68588 375638 69043 0 3 0x82 nanosleep syz-executor0 69043 205772 94410 0 3 0x82 thrsleep syz-fuzzer 69043 420857 94410 0 3 0x4000082 thrsleep syz-fuzzer 69043 57016 94410 0 3 0x4000082 thrsleep syz-fuzzer 69043 286644 94410 0 3 0x4000082 thrsleep syz-fuzzer 69043 357253 94410 0 3 0x4000082 thrsleep syz-fuzzer 69043 224826 94410 0 3 0x4000082 thrsleep syz-fuzzer 69043 353691 94410 0 3 0x4000082 thrsleep syz-fuzzer 69043 235645 94410 0 3 0x4000082 thrsleep syz-fuzzer 69043 93418 94410 0 3 0x4000082 thrsleep syz-fuzzer 69043 245482 94410 0 3 0x4000082 kqread syz-fuzzer 94410 261511 29094 0 3 0x10008a pause ksh 29094 347004 20368 0 3 0x92 select sshd 20368 90295 1 0 3 0x80 select sshd 92753 163959 47552 73 3 0x100010 ffs_fsync syslogd 47552 154953 1 0 3 0x100082 netio syslogd 97655 158626 1 77 3 0x100090 poll dhclient 75068 296434 1 0 3 0x80 poll dhclient 41792 95716 0 0 2 0x14200 zerothread 21692 27620 0 0 3 0x14200 aiodoned aiodoned 22870 428475 0 0 3 0x14200 syncer update 92401 179828 0 0 3 0x14200 cleaner cleaner 97139 374932 0 0 3 0x14200 reaper reaper 45751 83953 0 0 3 0x14200 pgdaemon pagedaemon 34290 261044 0 0 3 0x14200 bored crynlk 23898 345007 0 0 3 0x14200 bored crypto 14239 467622 0 0 3 0x40014200 acpi0 acpi0 88428 129723 0 0 3 0x40014200 idle1 82659 175311 0 0 3 0x14200 bored softnet 29207 341802 0 0 3 0x14200 bored systqmp 99591 135980 0 0 3 0x14200 bored systq 13355 114246 0 0 3 0x40014200 bored softclock 16664 121623 0 0 3 0x40014200 idle0 1 406514 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper