syzbot


panic: rw_enter: vmmaplk locking against myself

Status: auto-closed as invalid on 2019/06/06 09:22
Reported-by: syzbot+9f075132e115113be119@syzkaller.appspotmail.com
First crash: 2177d, last: 2175d

Sample crash report:
panic: rw_enter: vmmaplk locking against myself
Stopped at      db_enter+0xa:   popq    %rbp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*307710  23359      0         0x2          0    0  syz-executor1
db_enter() at db_enter+0xa
panic() at panic+0x147
_rw_enter(0,ffff800014aa1d68) at _rw_enter+0x2fa
uvmfault_lookup(1,ffffff00356cb220) at uvmfault_lookup+0x99
uvm_fault(ffff800014ad1790,ffff800014a9d000,0,6000118) at uvm_fault+0x6e
pageflttrap() at pageflttrap+0x197
kerntrap(0) at kerntrap+0x7c
alltraps_kern(6,42,6000100,0,0,1) at alltraps_kern+0x7b
_bpf_mtap(ffff800000074340,1,ffff800000074340,ffffff003499bc00) at _bpf_mtap+0x68
bpf_mtap_ether(ffff800014aa21d0,42,ffff800000074340) at bpf_mtap_ether+0xeb
ifiq_input(ffff800000171050,ffff800000171290,ffffff003499bc00) at ifiq_input+0x105
vio_rxeof(ffff800000171050) at vio_rxeof+0x220
vio_rx_intr(ffffffff) at vio_rx_intr+0x23
virtio_check_vqs(ffff80000001c300) at virtio_check_vqs+0x166
end trace frame: 0xffff800014aa22c8, count: 0
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ddb> 
ddb> set $lines = 0
ddb> show panic
rw_enter: vmmaplk locking against myself
ddb> trace
db_enter() at db_enter+0xa
panic() at panic+0x147
_rw_enter(0,ffff800014aa1d68) at _rw_enter+0x2fa
uvmfault_lookup(1,ffffff00356cb220) at uvmfault_lookup+0x99
uvm_fault(ffff800014ad1790,ffff800014a9d000,0,6000118) at uvm_fault+0x6e
pageflttrap() at pageflttrap+0x197
kerntrap(0) at kerntrap+0x7c
alltraps_kern(6,42,6000100,0,0,1) at alltraps_kern+0x7b
_bpf_mtap(ffff800000074340,1,ffff800000074340,ffffff003499bc00) at _bpf_mtap+0x68
bpf_mtap_ether(ffff800014aa21d0,42,ffff800000074340) at bpf_mtap_ether+0xeb
ifiq_input(ffff800000171050,ffff800000171290,ffffff003499bc00) at ifiq_input+0x105
vio_rxeof(ffff800000171050) at vio_rxeof+0x220
vio_rx_intr(ffffffff) at vio_rx_intr+0x23
virtio_check_vqs(ffff80000001c300) at virtio_check_vqs+0x166
intr_handler(0,ffff80000024b980) at intr_handler+0x3f
Xintr_ioapic_edge19_untramp(0,ffffffff81b50a90,0,18041969,0,a) at Xintr_ioapic_edge19_untramp+0x19f
Xspllower(ae487ec000,1,ffffff003f12a240,0,ffffffff81348301,ae487dc000) at Xspllower+0xc
pmap_write_protect(ffffff002caa91a8,ffffff0031397d48,ae487dc000,1) at pmap_write_protect+0x328
uvm_mapent_forkcopy(ae487dc000,ffffff0031397370,ffffff00356cb430,10000,ffffff002caa91a8) at uvm_mapent_forkcopy+0x19d
uvmspace_fork(ffff8000149fa960) at uvmspace_fork+0x1c9
process_new(ffffffff81a1f750,1,ffff800014ad1790) at process_new+0x1d9
fork1() at fork1+0x26d
syscall(0) at syscall+0x3e4
Xsyscall(6,2,0,2,0,7f7ffffcf920) at Xsyscall+0x128
end of kernel
end trace frame: 0x7f7ffffcf8d0, count: -24
ddb> show registers
rdi               0xffffffff81e22360    kprintf_mutex
rsi                              0x5
rbp               0xffff800014aa1b80
rbx               0xffff800014aa1c20
rdx                            0x3fd
rcx                                0
rax                              0x1
r8                0xffff800014aa1b50
r9                0x8080808080808080
r10               0xffff800014aa2388
r11               0xffffffff81550c30    x86_bus_space_io_read_1
r12                     0x3000000008
r13               0xffff800014aa1b90
r14                            0x100
r15               0xffffffff81c0ba78    apollo_udma33_tim+0x278a
rip               0xffffffff81425d5a    db_enter+0xa
cs                               0x8
rflags                         0x202
rsp               0xffff800014aa1b80
ss                              0x10
db_enter+0xa:   popq    %rbp
ddb> show proc
PROC (syz-executor1) pid=307710 stat=onproc
    flags process=2<EXEC> proc=0
    pri=81, usrpri=81, nice=20
    forw=0xffffffffffffffff, list=0xffff800014ad04d0,0xffff800014ad0738
    process=0xffff8000149fa960 user=0xffff800014a9d000, vmspace=0xffffff00356cb220
    estcpu=31, cpticks=0, pctcpu=0.1
    user=0, sys=0, intr=0
ddb> ps
   PID     TID   PPID    UID  S       FLAGS  WAIT          COMMAND
 59961  344347  76114      0  3        0x82  netio         sshd
 48883  277392  63196      0  2         0x2                syz-executor0
*23359  307710  63196      0  7         0x2                syz-executor1
 26393  262929      1      0  3    0x100083  ttyin         getty
 49012   80930      0      0  3     0x14200  bored         sosplice
 63196  515702  76471      0  3        0x82  thrsleep      syz-fuzzer
 63196  213031  76471      0  3   0x4000082  nanosleep     syz-fuzzer
 63196  296969  76471      0  3   0x4000082  thrsleep      syz-fuzzer
 63196  424934  76471      0  2   0x4000002                syz-fuzzer
 63196  252116  76471      0  3   0x4000082  thrsleep      syz-fuzzer
 63196  183552  76471      0  3   0x4000082  thrsleep      syz-fuzzer
 63196  438253  76471      0  3   0x4000082  thrsleep      syz-fuzzer
 76471  109035  51628      0  3    0x10008a  pause         ksh
 51628  477330  76114      0  3        0x92  select        sshd
 76114  199970      1      0  3        0x80  select        sshd
 89824  405661  41802     73  3    0x100090  kqread        syslogd
 41802  415429      1      0  3    0x100082  netio         syslogd
 39618  194209      1     77  3    0x100090  poll          dhclient
 99392  135723      1      0  3        0x80  poll          dhclient
 91654   53756      0      0  3     0x14200  pgzero        zerothread
 58662   27038      0      0  3     0x14200  aiodoned      aiodoned
 63053  476172      0      0  3     0x14200  syncer        update
 63125  130268      0      0  3     0x14200  cleaner       cleaner
 87618  411992      0      0  3     0x14200  reaper        reaper
 91680  292050      0      0  3     0x14200  pgdaemon      pagedaemon
 39401  323472      0      0  3     0x14200  bored         crynlk
 92278    3203      0      0  3     0x14200  bored         crypto
 79060  174491      0      0  3  0x40014200  acpi0         acpi0
 91395  379484      0      0  3     0x14200  bored         softnet
 68546  455496      0      0  3     0x14200  bored         systqmp
 89133  190330      0      0  3     0x14200  bored         systq
 82814  199638      0      0  3  0x40014200  bored         softclock
 39740  188873      0      0  3  0x40014200                idle0
     1   21314      0      0  3        0x82  wait          init
     0       0     -1      0  3     0x10200  scheduler     swapper

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/12/08 09:21 openbsd 696945d58559 6ae0ca72 .config console log report ci-openbsd-main
2018/12/07 22:44 openbsd 53ac6a98736c 65ed2472 .config console log report ci-openbsd-main
2018/12/06 10:18 openbsd 7d03a16b0321 f162ad97 console log report ci-openbsd-main
* Struck through repros no longer work on HEAD.