syzbot


panic: _mtx_lock_sleep: recursed on non-recursive mutex process lock @ /syzkaller/managers/i386/kernel/sys/kern/kern_eve

Status: fixed on 2021/05/12 08:32
Reported-by: syzbot+0a2bf09260110e4e9c91@syzkaller.appspotmail.com
Fix commit: 75c5cf7a720f filt_timerexpire: avoid process lock recursion
First crash: 1321d, last: 1319d

Sample crash report:
panic: _mtx_lock_sleep: recursed on non-recursive mutex process lock @ /syzkaller/managers/i386/kernel/sys/kern/kern_event.c:745

cpuid = 0
time = 1618354298
KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0x47/frame 0xfffffe00517c0700
vpanic() at vpanic+0x1c7/frame 0xfffffe00517c0760
panic() at panic+0x43/frame 0xfffffe00517c07c0
__mtx_lock_sleep() at __mtx_lock_sleep+0x6e9/frame 0xfffffe00517c0850
__mtx_lock_flags() at __mtx_lock_flags+0x150/frame 0xfffffe00517c08b0
filt_timerexpire() at filt_timerexpire+0x1de/frame 0xfffffe00517c0900
kqtimer_proc_continue() at kqtimer_proc_continue+0x11e/frame 0xfffffe00517c0950
tdsendsignal() at tdsendsignal+0x9f6/frame 0xfffffe00517c0a00
kern_kill() at kern_kill+0x203/frame 0xfffffe00517c0ab0
ia32_syscall() at ia32_syscall+0x237/frame 0xfffffe00517c0bf0
int0x80_syscall_common() at int0x80_syscall_common+0x9c/frame 0xffffd6c8
KDB: enter: panic
[ thread pid 783 tid 100107 ]
Stopped at      kdb_enter+0x67: movq    $0,0x143c86e(%rip)
db> 
db> set $lines = 0
db> set $maxwidth = 0
db> show registers
cs                        0x20
ds                        0x3b
es                        0x3b
fs                        0x13
gs                        0x1b
ss                           0
rax                       0x12
rcx         0xffffffff81134870  vprintf+0x140
rdx                        0x1
rbx                          0
rsp         0xfffffe00517c06e0
rbp         0xfffffe00517c0700
rsi                          0
rdi         0xffffffff811348a6  vprintf+0x176
r8                           0
r9          0x8080808080808080
r10         0xfffffe00517c05d0
r11              0x1ffaefff59c
r12         0xffffffff82067ac0  ddb_dbbe
r13                          0
r14         0xffffffff81a607dc
r15         0xffffffff81a607dc
rip         0xffffffff8112b897  kdb_enter+0x67
rflags                0x200082  kernload+0x82
kdb_enter+0x67: movq    $0,0x143c86e(%rip)
db> show proc
Process 783 (syz-executor.0) at 0xfffff800193db538:
 state: NORMAL
 uid: 0  gids: 0, 0, 5
 parent: pid 780 at 0xfffff80004eb8538
 ABI: FreeBSD ELF32
 flag: 0x10004000  flag2: 0
 arguments: /root/syz-executor.0
 reaper: 0xfffff80004457538 reapsubtree: 1
 sigparent: 20
 vmspace: 0xfffffe0094bab3e0
   (map 0xfffffe0094bab3e0)
   (map.pmap 0xfffffe0094bab4a0)
   (pmap 0xfffffe0094bab500)
 threads: 1
100107                   Run     CPU 0                       syz-executor.0
db> ps
  pid  ppid  pgrp   uid  state   wmesg   wchan               cmd
 9178   788   788     0  R       (threaded)                  syz-executor.2
106303                   RunQ                                syz-executor.2
113060                   S       kqread  0xfffff80019ec1200  syz-executor.2
113061                   RunQ                                syz-executor.2
113062                   RunQ                                syz-executor.2
 9177   825   825     0  T       (threaded)                  syz-executor.3
112610                   s                                   syz-executor.3
113056                   RunQ                                syz-executor.3
113057                   RunQ                                syz-executor.3
 9176   784   784     0  T       (threaded)                  syz-executor.1
100112                   s                                   syz-executor.1
113052                   RunQ                                syz-executor.1
113053                   RunQ                                syz-executor.1
 9175   783   783     0  T       (threaded)                  syz-executor.0
106422                   s                                   syz-executor.0
113048                   RunQ                                syz-executor.0
113049                   RunQ                                syz-executor.0
113050                   RunQ                                syz-executor.0
113051                   RunQ                                syz-executor.0
 6242  6241   784     0  SV      uwait   0xfffff8007a025380  syz-executor.1
 6241     1   784     0  RV                                  syz-executor.1
 5329  5327   784     0  SV      uwait   0xfffff80019b6f800  syz-executor.1
 5328  5327   784     0  S       uwait   0xfffff8001954d580  syz-executor.1
 5327     1   784     0  RV                                  syz-executor.1
 5326     1   784     0  S       uwait   0xfffff80019b6f500  syz-executor.1
 5323     1   784     0  S       uwait   0xfffff80019b6f700  syz-executor.1
 5322     1   784     0  S       uwait   0xfffff80019b6f100  syz-executor.1
 5196     1   784     0  S       uwait   0xfffff80019cf4a80  syz-executor.1
 5195     1   784     0  S       uwait   0xfffff8001930fa80  syz-executor.1
 5181     1   784     0  S       uwait   0xfffff80019cf4380  syz-executor.1
 5180     1   784     0  S       uwait   0xfffff8001930fc80  syz-executor.1
 5160  5159   784     0  SV      uwait   0xfffff8001954d500  syz-executor.1
 5159     1   784     0  RV                                  syz-executor.1
 5155     1   784     0  S       uwait   0xfffff80019b6f600  syz-executor.1
 5154     1   784     0  S       uwait   0xfffff8007a025c80  syz-executor.1
 5059     1   784     0  S       uwait   0xfffff80004b9f680  syz-executor.1
 5044  5042   784     0  SV      uwait   0xfffff80019cf4580  syz-executor.1
 5042     1   784     0  RV                                  syz-executor.1
 5038     1   825     0  S       uwait   0xfffff8001930fb80  syz-executor.3
 5033     1   825     0  S       umtxn   0xfffff80004a99900  syz-executor.3
 4387  4386   788     0  SV      uwait   0xfffff8001954d400  syz-executor.2
 4386     1   788     0  RV                                  syz-executor.2
 4163     1  4163    65  Ss      select  0xfffff80019e71740  dhclient
 3892     1   825     0  S       uwait   0xfffff8001954d100  syz-executor.3
 3890     1   825     0  S       uwait   0xfffff80019cf4d00  syz-executor.3
 3482     1  3482     0  Ss      select  0xfffff8007a0c6dc0  dhclient
 3479     1  3479     0  Ss      select  0xfffff8007a0c6ec0  dhclient
 3460     1  3460    65  Rs                                  dhclient
 2867     1  2867     0  Ss      select  0xfffff80019e71f40  dhclient
 2864     1  2864     0  Ss      select  0xfffff80019e71cc0  dhclient
 2845     1  2845    65  Ss      select  0xfffff800044df240  dhclient
 2226     1  2226     0  Ss      select  0xfffff80019e71d40  dhclient
 2223     1  2223     0  Ss      select  0xfffff800046cc240  dhclient
 2204     1  2204    65  Ss      select  0xfffff800046cc4c0  dhclient
 2035     1   825     0  SV      uwait   0xfffff8001930f380  syz-executor.3
 2028     1   825     0  SV      uwait   0xfffff8001932f100  syz-executor.3
 1924  1919   783     0  SV      uwait   0xfffff80019cf4780  syz-executor.0
 1919     1   783     0  RV                                  syz-executor.0
  977     1   977     0  Ss      select  0xfffff800046cc340  dhclient
  974     1   974     0  Ss      select  0xfffff800044df940  dhclient
  825   780   825     0  Rs                                  syz-executor.3
  788   780   788     0  Rs                                  syz-executor.2
  784   780   784     0  Rs                                  syz-executor.1
  783   780   783     0  Rs      CPU 0                       syz-executor.0
  780   778   778     0  R       (threaded)                  syz-fuzzer
100099                   S       uwait   0xfffff80004a99200  syz-fuzzer
100115                   S       uwait   0xfffff8001932fd00  syz-fuzzer
100116                   S       uwait   0xfffff8001932fe00  syz-fuzzer
100117                   S       uwait   0xfffff8001932ff00  syz-fuzzer
100118                   S       uwait   0xfffff8001930f680  syz-fuzzer
100119                   S       uwait   0xfffff8001930f580  syz-fuzzer
100120                   RunQ                                syz-fuzzer
100121                   S       uwait   0xfffff8001954d980  syz-fuzzer
100122                   S       uwait   0xfffff8001954da80  syz-fuzzer
  778   776   778     0  Ss      pause   0xfffff80019335b20  csh
  776   694   776     0  Ss      select  0xfffff800046ce840  sshd
  760     1   760     0  Rs+                                 getty
  759     1   759     0  Ss+     ttyin   0xfffff80004bbb0b0  getty
  758     1   758     0  Ss+     ttyin   0xfffff80004bbb4b0  getty
  757     1   757     0  Ss+     ttyin   0xfffff80004bbb8b0  getty
  756     1   756     0  Ss+     ttyin   0xfffff80004bbbcb0  getty
  755     1   755     0  Ss+     ttyin   0xfffff80004b490b0  getty
  754     1   754     0  Ss+     ttyin   0xfffff80004b494b0  getty
  753     1   753     0  Ss+     ttyin   0xfffff80004b498b0  getty
  752     1   752     0  Ss+     ttyin   0xfffff80004b49cb0  getty
  698     1   698     0  Ss      nanslp  0xffffffff8253b8a0  cron
  694     1   694     0  Ss      select  0xfffff800046cea40  sshd
  507     1   507     0  Ss      select  0xfffff800044dfcc0  syslogd
  436     1   436     0  Ss      select  0xfffff800044dfc40  devd
  435     1   435    65  Ss      select  0xfffff800044dfe40  dhclient
  350     1   350     0  Ss      select  0xfffff800046cecc0  dhclient
  347     1   347     0  Ss      select  0xfffff800046ced40  dhclient
   23     0     0     0  RL                                  [vnlru]
   22     0     0     0  RL                                  [syncer]
   21     0     0     0  RL      (threaded)                  [bufdaemon]
100080                   D       qsleep  0xffffffff82629d80  [bufdaemon]
100085                   D       -       0xffffffff8200ad80  [bufspacedaemon-0]
100095                   RunQ                                [/ worker]
   20     0     0     0  DL      psleep  0xffffffff82651b88  [vmdaemon]
   19     0     0     0  DL      (threaded)                  [pagedaemon]
100078                   D       psleep  0xffffffff82645ff8  [dom0]
100086                   D       launds  0xffffffff82646004  [laundry: dom0]
100087                   D       umarcl  0xffffffff815b8d40  [uma]
   18     0     0     0  DL      -       0xffffffff8236fbe8  [rand_harvestq]
   17     0     0     0  DL      waiting 0xffffffff82c31818  [sctp_iterator]
   16     0     0     0  RL                                  [pf purge]
   15     0     0     0  DL      -       0xffffffff826273dc  [soaiod4]
    9     0     0     0  DL      -       0xffffffff826273dc  [soaiod3]
    8     0     0     0  RL                                  [soaiod2]
    7     0     0     0  RL                                  [soaiod1]
    6     0     0     0  DL      (threaded)                  [cam]
100043                   D       -       0xffffffff822470c0  [doneq0]
100044                   D       -       0xffffffff82247040  [async]
100077                   D       -       0xffffffff82246f10  [scanner]
   14     0     0     0  DL      seqstat 0xfffff80004510888  [sequencer 00]
    5     0     0     0  DL      crypto_ 0xfffff800044ae280  [crypto returns 1]
    4     0     0     0  DL      crypto_ 0xfffff800044ae230  [crypto returns 0]
    3     0     0     0  DL      crypto_ 0xffffffff82643520  [crypto]
   13     0     0     0  DL      (threaded)                  [geom]
100034                   D       -       0xffffffff8251b0a0  [g_event]
100035                   D       -       0xffffffff8251b0a8  [g_up]
100036                   D       -       0xffffffff8251b0b0  [g_down]
    2     0     0     0  DL      (threaded)                  [KTLS]
100027                   D       -       0xfffff80004344b00  [thr_0]
100028                   D       -       0xfffff80004344b80  [thr_1]
   12     0     0     0  RL      (threaded)                  [intr]
100014                   I                                   [swi6: task queue]
100016                   I                                   [swi6: Giant taskq]
100018                   I                                   [swi5: fast taskq]
100029                   I                                   [swi1: netisr 0]
100030                   I                                   [swi3: vm]
100031                   I                                   [swi4: clock (0)]
100032                   Run     CPU 1                       [swi4: clock (1)]
100045                   I                                   [irq24: virtio_pci0]
100046                   I                                   [irq25: virtio_pci0]
100047                   I                                   [irq26: virtio_pci0]
100048                   I                                   [irq27: virtio_pci0]
100049                   I                                   [irq28: virtio_pci1]
100050                   I                                   [irq29: virtio_pci1]
100051                   I                                   [irq30: virtio_pci1]
100052                   I                                   [irq31: virtio_pci1]
100053                   I                                   [irq32: virtio_pci1]
100058                   I                                   [irq10: virtio_pci2]
100060                   I                                   [irq1: atkbd0]
100061                   I                                   [irq12: psm0]
100062                   I                                   [swi0: uart uart++]
100070                   I                                   [swi1: pf send]
100083                   I                                   [swi1: hpts]
100084                   I                                   [swi1: hpts]
   11     0     0     0  RL      (threaded)                  [idle]
100003                   CanRun                              [idle: cpu0]
100004                   CanRun                              [idle: cpu1]
    1     0     1     0  SLs     wait    0xfffff80004457538  [init]
   10     0     0     0  DL      audit_w 0xffffffff82643a30  [audit]
    0     0     0     0  RLs     (threaded)                  [kernel]
100000                   D       swapin  0xffffffff8251b630  [swapper]
100005                   D       -       0xfffff80004089800  [softirq_0]
100006                   D       -       0xfffff80004089700  [softirq_1]
100007                   D       -       0xfffff80004089600  [if_io_tqg_0]
100008                   D       -       0xfffff80004089500  [if_io_tqg_1]
100009                   D       -       0xfffff80004089400  [if_config_tqg_0]
100010                   D       -       0xfffff8000434bd00  [in6m_free taskq]
100011                   D       -       0xfffff8000434bc00  [kqueue_ctx taskq]
100012                   D       -       0xfffff8000434bb00  [inm_free taskq]
100013                   D       -       0xfffff8000434ba00  [linuxkpi_irq_wq]
100015                   D       -       0xfffff8000434b800  [aiod_kick taskq]
100017                   RunQ                                [thread taskq]
100019                   D       -       0xfffff8000434b400  [linuxkpi_short_wq_0]
100020                   D       -       0xfffff8000434b400  [linuxkpi_short_wq_1]
100021                   D       -       0xfffff8000434b400  [linuxkpi_short_wq_2]
100022                   D       -       0xfffff8000434b400  [linuxkpi_short_wq_3]
100023                   D       -       0xfffff8000434b300  [linuxkpi_long_wq_0]
100024                   D       -       0xfffff8000434b300  [linuxkpi_long_wq_1]
100025                   D       -       0xfffff8000434b300  [linuxkpi_long_wq_2]
100026                   D       -       0xfffff8000434b300  [linuxkpi_long_wq_3]
100033                   D       -       0xfffff8000434b200  [firmware taskq]
100037                   D       -       0xfffff8000434b100  [crypto_0]
100038                   D       -       0xfffff8000434b100  [crypto_1]
100054                   D       -       0xfffff8000469ec00  [vtnet0 rxq 0]
100055                   D       -       0xfffff8000469eb00  [vtnet0 txq 0]
100056                   D       -       0xfffff8000469ea00  [vtnet0 rxq 1]
100057                   D       -       0xfffff8000469e900  [vtnet0 txq 1]
100059                   D       vtbslp  0xfffff800046cf080  [virtio_balloon]
100063                   D       -       0xfffff8000469e800  [mca taskq]
100066                   D       -       0xffffffff81e0c230  [deadlkres]
100073                   D       -       0xfffff80004b4ce00  [acpi_task_0]
100074                   D       -       0xfffff80004b4ce00  [acpi_task_1]
100075                   D       -       0xfffff80004b4ce00  [acpi_task_2]
100076                   D       -       0xfffff8000434b000  [CAM taskq]
db> show all locks
Process 783 (syz-executor.0) thread 0xfffffe0094bcda00 (100107)
exclusive sleep mutex process lock (process lock) r = 0 (0xfffff8007a43e128) locked @ /syzkaller/managers/i386/kernel/sys/kern/kern_proc.c:450
db> show malloc
              Type        InUse        MemUse     Requests
           pf_hash            5        11524K            5
            devbuf         4216         4340K         4244
          tcp_hpts            5         3201K            5
             vtbuf           24         1968K           46
         sysctloid        30935         1814K        31002
              kobj          332         1328K          492
            newblk            8         1026K         8725
          vfscache            3         1025K            3
          filedesc           74          586K        16365
               pcb           56          569K         4723
          inodedep          143          566K         8319
         ufs_quota            1          512K            1
          vfs_hash            1          512K            1
           callout            2          512K            2
              intr            4          472K            4
           subproc          201          409K         9289
            acpica         1674          184K        55406
         vnet_data            1          168K            1
           tidhash            3          141K            3
           pagedep            9          130K         8164
        tfo_ccache            1          128K            1
            DEVFS1          106          106K          123
               sem            4          106K            4
            linker          287          101K          322
               BPF           46           88K           46
               bus          995           81K         3509
          mtx_pool            2           72K            2
          syncache            1           68K            1
          acpitask            1           64K            1
       ddb_capture            1           64K            1
            module          507           64K          507
           kdtrace          285           54K        22242
              umtx          414           52K          414
            dirrem          134           34K         8236
              temp           35           33K         3122
         hostcache            1           32K            1
               shm            1           32K            4
            DEVFS3          125           32K          135
               msg            4           30K            4
              vmem            3           26K            4
        gtaskqueue           18           26K           18
            kbdmux            6           22K            6
            ifaddr           71           21K           73
        DEVFS_RULE           56           20K           56
          freefile          134           17K         8220
         ufs_mount            5           17K            6
              proc            3           17K            3
               tty           16           16K           16
           ithread           99           16K           99
            bus-sc           33           14K         1719
       ether_multi          157           13K          167
            KTRACE          100           13K          100
            kqueue          111           13K        13277
           lltable           41           13K          164
             ifnet            7           13K            7
              kenv           93           12K           93
      eventhandler          133           12K          133
              ksem           11           11K         3231
              rman           84           10K          425
              GEOM           60           10K          488
         in6_multi           71            9K           71
         bmsafemap            2            9K         8305
              UART           12            9K           12
           devstat            4            9K            4
               rpc            2            8K            2
             shmfd            1            8K           41
       pfs_vncache            1            8K            1
         pfs_nodes           20            8K           20
     audit_evclass          236            8K          294
         sctp_timw           29            8K           29
              cred           26            7K          296
            sglist            5            7K            5
           CAM DEV            3            6K          510
            plimit           24            6K          458
         taskqueue           57            6K           57
           pwddesc           92            6K         9179
         sctp_atcl           14            6K         1075
         CAM queue            5            6K         1528
            DEVFSP           78            5K           82
       ufs_dirhash           24            5K           24
           session           35            5K           52
               UMA          263            5K          263
          pf_ifnet           10            5K           19
                vt           11            5K           11
           memdesc            1            4K            1
               MCA           32            4K           32
             evdev            4            4K            4
          kcovinfo           64            4K           68
          routetbl           23            4K           23
           acpisem           28            4K           28
             selfd           55            4K       131679
             lockf           32            4K          940
             hhook           13            4K           13
       fpukern_ctx            3            3K            3
         proc-args           52            3K          702
          terminal           11            3K           11
            select           19            3K          799
           uidinfo            3            3K           14
        local_apic            1            2K            1
           io_apic            1            2K            1
         ipsec-saq            2            2K            2
            ip6ndp           12            2K           15
          sctp_ifa           14            2K           15
            Unitno           29            2K           51
           CAM XPT           22            2K          543
          in_multi            6            2K            8
       ipsecpolicy            2            2K            2
           acpidev           20            2K           20
               msi            9            2K            9
             clone            9            2K            9
               tun            7            2K            7
           softdep            1            1K            1
             mkdir            8            1K        16288
            sahead            1            1K            1
          secasvar            1            1K            1
             nhops            6            1K            8
       vnodemarker            2            1K           74
      NFSD session            1            1K            1
       inpcbpolicy           29            1K         4377
          freework            4            1K         8140
        CAM periph            4            1K          271
             ipsec            3            1K            3
          sctp_ifn            6            1K           15
          freeblks            3            1K         8139
               mld            6            1K            6
              igmp            6            1K            6
         toponodes            6            1K            6
            isadev            6            1K            6
             mount           16            1K           89
          pci_link           10            1K           10
            crypto            4            1K            4
 encap_export_host           12            1K           12
          procdesc            5            1K           18
      linuxcurrent            3            1K            4
         newdirblk            4            1K         8144
            diradd            4            1K         8276
              pfil            4            1K            4
           CAM SIM            2            1K            2
              cdev            2            1K            2
         sctp_atky           14            1K         1151
    chacha20random            1            1K            1
               osd            3            1K           10
      NFSD lckfile            1            1K            1
     NFSD V4client            1            1K            1
             DEVFS            9            1K           10
            vnodes            1            1K            1
              ktls            1            1K            1
         sctp_athm           14            1K         1075
            feeder            7            1K            7
           tcpfunc            3            1K            3
        loginclass            3            1K            6
            prison            6            1K            6
             sigio            3            1K           77
             linux            5            1K            6
        aesni_data            2            1K            2
            apmdev            1            1K            1
          atkbddev            2            1K            2
     CAM dev queue            2            1K            2
 CAM I/O Scheduler            1            1K            1
          CAM path            4            1K         1034
          pmchooks            1            1K            1
          nexusdev            7            1K            7
            soname            4            1K         8590
          filecaps            5            1K          116
          sctp_vrf            1            1K            1
              vnet            1            1K            1
           entropy            2            1K           45
          acpiintr            1            1K            1
               pmc            1            1K            1
              cpus            2            1K            2
    vnet_data_free            1            1K            1
           Per-cpu            1            1K            1
          p1003.1b            1            1K            1
          pf_table            0            0K            0
           pf_rule            0            0K            0
           pf_altq            0            0K            0
           pf_osfp            0            0K            0
           pf_temp            0            0K            0
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ag_portal_data_t malloc            0            0K            0
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db> show uma
              Zone   Size    Used    Free    Requests  Sleeps  Bucket  Total Mem    XFree
   mbuf_jumbo_page   4096    8338     929     1353347       0     254   37957632        0
              pbuf   2624       0     973           0       0       2    2553152        0
              mbuf    256    8915     625     2071409       0     254    2442240        0
        RADIX NODE    144   14596     241      337410       0      62    2136528        0
          BUF TRIE    144     175   13293         965       0      62    1939392        0
        malloc-384    384    4240      10        4241       0      30    1632000        0
        malloc-128    128   10711      77       19803       0     126    1380864        0
       malloc-4096   4096     333       3         578       0       2    1376256        0
       UMA Slabs 0    112   10503       6       10503       0     126    1177008        0
      mbuf_cluster   2048     570       2         570       0     254    1171456        0
      malloc-16384  16384      37       4        8181       0       1     671744        0
         FFS inode   1160     530      23        8750       0       8     641480        0
       malloc-4096   4096     116       4        9745       0       2     491520        0
         VM OBJECT    264    1614      66      135138       0      30     443520        0
            THREAD   1792     192      15       13062       0       8     370944        0
      malloc-65536  65536       5       0           5       0       1     327680        0
      malloc-65536  65536       4       1          12       0       1     327680        0
         MAP ENTRY     96    2896     254      499930       0     126     302400        0
             VNODE    448     567      90        8789       0      30     294336        0
        256 Bucket   2048     121      15       17905       0       8     278528        0
        malloc-384    384     142     538        8357       0      30     261120        0
        malloc-256    256     178     767        9100       0      62     241920        0
         malloc-64     64    3386     205       12553       0     254     229824        0
         tcp_inpcb    488      14     442        3761       0     254     222528        0
            DEVCTL   1024       0     216         131       0       0     221184        0
         malloc-16     16   12834     166       12947       0     254     208000        0
        malloc-256    256     263     517       12365       0      62     199680        0
        malloc-256    256     303     447       23154       0      62     192000        0
        malloc-128    128    1370     118       30144       0     126     190464        0
         UMA Zones    768     235       4         235       0      16     183552        0
           VMSPACE   2544      62      10        9148       0       4     183168        0
         malloc-32     32    4880     160        4945       0     254     161280        0
       mbuf_packet    256      19     551        9294       0     254     145920        0
              PROC   1336      91      17        9178       0       8     144288        0
       FFS2 dinode    256     530      25        8750       0      62     142080        0
       S VFS Cache    104    1028     337        9573       0     126     141960        0
            socket    944      68      80        7305       0     254     139712        0
      malloc-65536  65536       0       2         300       0       1     131072        0
      malloc-65536  65536       0       2         136       0       1     131072        0
       malloc-1024   1024     119       5         784       0      16     126976        0
         vmem btag     56    2200      20        2200       0     254     124320        0
       malloc-2048   2048      20      40        1236       0       8     122880        0
         filedesc0   1072      92      20        9179       0       8     120064        0
          ksiginfo    112      93     951        1553       0     126     116928        0
             tcpcb   1048      14      85        3761       0     254     103752        0
        malloc-128    128     755      51        3969       0     126     103168        0
      malloc-32768  32768       1       2         131       0       1      98304        0
       malloc-2048   2048       5      43        3304       0       8      98304        0
       malloc-4096   4096      22       0          22       0       2      90112        0
        malloc-128    128     151     531        8245       0     126      87296        0
          UMA Kegs    384     220       3         220       0      30      85632        0
        128 Bucket   1024      50      33        1280       0      16      84992        0
           sctp_ep   1280      14      52         999       0     254      84480        0
            clpbuf   2624       0      32          19       0      16      83968        0
         sctp_asoc   2288       0      35          76       0     254      80080        0
       malloc-8192   8192       7       2         110       0       1      73728        0
             g_bio    408       0     170        7469       0      30      69360        0
      malloc-16384  16384       4       0           4       0       1      65536        0
         64 Bucket    512      89      39        9546       0      30      65536        0
         malloc-64     64     806     139       10454       0     254      60480        0
       tcp_bbr_pcb    832       5      67        2103       0      16      59904        0
       malloc-8192   8192       7       0           7       0       1      57344        0
       malloc-2048   2048      16      12          34       0       8      57344        0
         32 Bucket    256      74     136        8157       0      62      53760        0
         malloc-64     64     704     115        4900       0     254      52416        0
        malloc-384    384      93      37         230       0      30      49920        0
      malloc-16384  16384       1       2         171       0       1      49152        0
              pipe    744      26      34        1119       0      16      44640        0
           DIRHASH   1024      34       6          34       0      16      40960        0
       malloc-1024   1024       3      37         119       0      16      40960        0
            pcpu-8      8    4632     488        4788       0     254      40960        0
             Files     80     285     215       32607       0     126      40000        0
        malloc-384    384      14      86        1076       0      30      38400        0
             NAMEI   1024       0      36       48891       0      16      36864        0
        malloc-512    512      10      62         521       0      30      36864        0
         malloc-64     64      86     481      131805       0     254      36288        0
        malloc-256    256      62      73        8734       0      62      34560        0
      malloc-32768  32768       1       0           1       0       1      32768        0
      malloc-32768  32768       1       0           1       0       1      32768        0
      malloc-16384  16384       1       1           7       0       1      32768        0
       malloc-8192   8192       4       0           4       0       1      32768        0
       malloc-1024   1024      26       6          27       0      16      32768        0
           pcpu-64     64     479      33         479       0     254      32768        0
        sctp_raddr    736       0      44          76       0     254      32384        0
         TURNSTILE    136     208      23         208       0      62      31416        0
       malloc-4096   4096       2       5        8348       0       2      28672        0
             KNOTE    160      34     141      521988       0      62      28000        0
        malloc-256    256      63      42         725       0      62      26880        0
       malloc-1024   1024      16       8        1352       0      16      24576        0
            ttyinq    160     135      15         300       0      62      24000        0
          8 Bucket     80      49     251        2640       0     126      24000        0
        malloc-128    128      27     159       24712       0     126      23808        0
      tcp_rack_pcb    704       0      33         200       0      16      23232        0
           ttyoutq    256      72      18         160       0      62      23040        0
               PWD     32      36     594        8240       0     254      20160        0
         malloc-64     64     160     155       25438       0     254      20160        0
        SLEEPQUEUE     88     208      16         208       0     126      19712        0
       Mountpoints   2752       2       5           2       0       4      19264        0
      malloc-16384  16384       1       0           1       0       1      16384        0
       malloc-8192   8192       0       2          30       0       1      16384        0
       malloc-8192   8192       2       0           2       0       1      16384        0
       malloc-8192   8192       2       0           2       0       1      16384        0
         malloc-64     64       8     244         319       0     254      16128        0
         malloc-32     32     349     155        4361       0     254      16128        0
      vtnet_tx_hdr     24       1     667      679879       0     254      16032        0
       tcp_bbr_map    128      14     110        3568       0     126      15872        0
        malloc-128    128      75      49         321       0     126      15872        0
        malloc-128    128      83      41         423       0     126      15872        0
         udp_inpcb    488      10      22         363       0     254      15616        0
             unpcb    256      20      40        1881       0     254      15360        0
        malloc-384    384      31       9          31       0      30      15360        0
        malloc-256    256       9      51       24589       0      62      15360        0
       malloc-4096   4096       1       2           4       0       2      12288        0
       malloc-4096   4096       1       2           7       0       2      12288        0
        malloc-512    512       0      24         118       0      30      12288        0
        malloc-512    512       7      17         148       0      30      12288        0
         malloc-32     32     152     226        2971       0     254      12096        0
         malloc-32     32      43     335         816       0     254      12096        0
         16 Bucket    144      51      33         287       0      62      12096        0
         malloc-16     16     471     279        5422       0     254      12000        0
             ripcb    488       5      19         161       0     254      11712        0
              kenv    258      15      30        1065       0      30      11610        0
     routing nhops    256      27      18          35       0      62      11520        0
       malloc-2048   2048       1       3          13       0       8       8192        0
       malloc-2048   2048       3       1           3       0       8       8192        0
       malloc-2048   2048       1       3           4       0       8       8192        0
       malloc-2048   2048       1       3           4       0       8       8192        0
       malloc-1024   1024       0       8          44       0      16       8192        0
       malloc-1024   1024       5       3           5       0      16       8192        0
       malloc-1024   1024       2       6          11       0      16       8192        0
       malloc-1024   1024       2       6           2       0      16       8192        0
        malloc-512    512       2      14          61       0      30       8192        0
        malloc-512    512      11       5          11       0      30       8192        0
           rtentry    176      31      15          35       0      62       8096        0
              PGRP     88      35      57          56       0     126       8096        0
          rl_entry     40      74     128          74       0     254       8080        0
sctp_stream_msg_out    112       0      72          31       0     254       8064        0
        sctp_laddr     48       0     168         271       0     254       8064        0
             udpcb     32      10     242         455       0     254       8064        0
         malloc-64     64       9     117          19       0     254       8064        0
         malloc-32     32      54     198        1549       0     254       8064        0
         malloc-32     32      42     210        8273       0     254       8064        0
         malloc-32     32      20     232          20       0     254       8064        0
         malloc-32     32      33     219        4387       0     254       8064        0
          4 Bucket     48       7     161         205       0     254       8064        0
          2 Bucket     32      48     204        1375       0     254       8064        0
         malloc-16     16      31     469        1292       0     254       8000        0
         malloc-16     16      30     470          84       0     254       8000        0
         malloc-16     16      37     463       26376       0     254       8000        0
         malloc-16     16      24     476          30       0     254       8000        0
         malloc-16     16       6     494           7       0     254       8000        0
        malloc-128    128      32      30          52       0     126       7936        0
      tcp_rack_map    120       0      66         210       0     126       7920        0
        sctp_chunk    152       0      52          29       0     254       7904        0
     udplite_inpcb    488       0      16          92       0     254       7808        0
            itimer    352       0      22           2       0      30       7744        0
        malloc-384    384       1      19         349       0      30       7680        0
        malloc-384    384       2      18           2       0      30       7680        0
        malloc-256    256      23       7         294       0      62       7680        0
     FPU_save_area    832       1       8           1       0      16       7488        0
            cpuset    104       7      55          15       0     126       6448        0
 epoch_record pcpu    256       4      12           4       0      62       4096        0
       malloc-4096   4096       0       1           2       0       2       4096        0
        malloc-512    512       1       7           1       0      30       4096        0
           pcpu-16     16       7     249           7       0     254       4096        0
    tcp_log_bucket    176       0      23           1       0      62       4048        0
          syncache    168       0      24           4       0     254       4032        0
         malloc-64     64       1      62           1       0     254       4032        0
         hostcache     80       1      49           1       0     254       4000        0
         malloc-16     16       0     250           1       0     254       4000        0
      tcp_log_node    120       0      33           2       0     126       3960        0
       UMA Slabs 1    176       9      13           9       0      62       3872        0
            mqnode    416       3       6           3       0      30       3744        0
        KMAP ENTRY     96      12      27          12       0       0       3744        0
              vmem   1856       1       1           1       0       8       3712        0
         domainset     40       0      63           6       0     254       2520        0
           SMR CPU     32       2      29           2       0     254        992        0
        SMR SHARED     24       2      29           2       0     254        744        0
       FFS1 dinode    128       0       0           0       0     126          0        0
             swblk    136       0       0           0       0      62          0        0
          swpctrie    144       0       0           0       0      62          0        0
   sctp_asconf_ack     48       0       0           0       0     254          0        0
       sctp_asconf     40       0       0           0       0     254          0        0
        sctp_readq    152       0       0           0       0     254          0        0
   pf state scrubs     40       0       0           0       0     254          0        0
   pf frag entries     40       0       0           0       0     254          0        0
          pf frags    248       0       0           0       0      62          0        0
  pf table entries    160       0       0           0       0      62          0        0
pf table entry counters     64       0       0           0       0     254          0        0
   pf source nodes    136       0       0           0       0     254          0        0
     pf state keys     88       0       0           0       0     126          0        0
         pf states    296       0       0           0       0     254          0        0
           pf tags    104       0       0           0       0     126          0        0
          pf mtags     48       0       0           0       0     254          0        0
    IPsec SA lft_c     16       0       0           0       0     254          0        0
           tcp_log    416       0       0           0       0     254          0        0
          tcpreass     48       0       0           0       0     254          0        0
tfo_ccache_entries     80       0       0           0       0     126          0        0
               tfo      4       0       0           0       0     254          0        0
          sackhole     32       0       0           0       0     254          0        0
             tcptw     88       0       0           0       0     254          0        0
               ipq     56       0       0           0       0     254          0        0
            AIOLIO    272       0       0           0       0      30          0        0
             AIOCB    552       0       0           0       0      16          0        0
              AIOP     32       0       0           0       0     254          0        0
               AIO    208       0       0           0       0      62          0        0
        mqnotifier    216       0       0           0       0      62          0        0
            mvdata     64       0       0           0       0     254          0        0
            mqueue    248       0       0           0       0      62          0        0
        TMPFS node    224       0       0           0       0      62          0        0
           NCLNODE    584       0       0           0       0      16          0        0
     LTS VFS Cache    360       0       0           0       0      30          0        0
       L VFS Cache    320       0       0           0       0      30          0        0
     STS VFS Cache    144       0       0           0       0      62          0        0
           cryptop    280       0       0           0       0      30          0        0
  linux_dma_object     24       0       0           0       0     254          0        0
  linux_dma_pctrie    144       0       0           0       0      62          0        0
   IOMMU_MAP_ENTRY    120       0       0           0       0     126          0        0
      ktls_session    192       0       0           0       0      62          0        0
    mbuf_jumbo_16k  16384       0       0           0       0     254          0        0
     mbuf_jumbo_9k   9216       0       0           0       0     254          0        0
      audit_record   1280       0       0           0       0       8          0        0
        MAC labels     40       0       0           0       0     254          0        0
            vnpbuf   2624       0       0           0       0      64          0        0
            mdpbuf   2624       0       0           0       0       3          0        0
           nfspbuf   2624       0       0           0       0      16          0        0
            swwbuf   2624       0       0           0       0       8          0        0
            swrbuf   2624       0       0           0       0      16          0        0
          umtx_shm     88       0       0           0       0     126          0        0
           umtx pi     96       0       0           0       0     126          0        0
rangeset pctrie nodes    144       0       0           0       0      62          0        0
      malloc-65536  65536       0       0           0       0       1          0        0
      malloc-65536  65536       0       0           0       0       1          0        0
      malloc-65536  65536       0       0           0       0       1          0        0
      malloc-65536  65536       0       0           0       0       1          0        0
      malloc-32768  32768       0       0           0       0       1          0        0
      malloc-32768  32768       0       0           0       0       1          0        0
      malloc-32768  32768       0       0           0       0       1          0        0
      malloc-32768  32768       0       0           0       0       1          0        0
      malloc-32768  32768       0       0           0       0       1          0        0
      malloc-16384  16384       0       0           0       0       1          0        0
      malloc-16384  16384       0       0           0       0       1          0        0
      malloc-16384  16384       0       0           0       0       1          0        0
       malloc-8192   8192       0       0           0       0       1          0        0
       malloc-8192   8192       0       0           0       0       1          0        0
       malloc-4096   4096       0       0           0       0       2          0        0
       malloc-2048   2048       0       0           0       0       8          0        0
        malloc-512    512       0       0           0       0      30          0        0
        malloc-512    512       0       0           0       0      30          0        0
        malloc-384    384       0       0           0       0      30          0        0
        malloc-256    256       0       0           0       0      62          0        0
           pcpu-32     32       0       0           0       0     254          0        0
            pcpu-4      4       0       0           0       0     254          0        0
            fakepg    104       0       0           0       0     126          0        0
          UMA Hash    256       0       0           0       0      62          0        0

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/04/13 22:51 freebsd-src ca6e1fa3ce87 a184b83e console log report ci-freebsd-i386 panic: _mtx_lock_sleep: recursed on non-recursive mutex process lock @ /syzkaller/managers/i386/kernel/sys/kern/kern_eve
2021/04/12 21:15 freebsd-src 5e98cae661f3 bfeda1b1 console log report ci-freebsd-i386 panic: _mtx_lock_sleep: recursed on non-recursive mutex process lock @ /syzkaller/managers/i386/kernel/sys/kern/kern_eve
* Struck through repros no longer work on HEAD.