panic: amap_pp_adjref: negative reference count (3)

Status: upstream: reported on 2026/05/30 16:03
Reported-by: syzbot+092fc16af93b8b67ef78@syzkaller.appspotmail.com
First crash: 60d, last: 46m
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
openbsd panic: amap_pp_adjref: negative reference count 2 syz, C 98 2439d 2491d 3/4 fixed on 2019/12/04 16:31
openbsd panic: amap_pp_adjref: negative reference count (2) 2 1 1386d 1386d 0/4 auto-obsoleted due to no activity on 2023/01/10 14:24

Sample crash report:
panic: amap_pp_adjref: negative reference count
Stopped at      db_enter+0x25:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
 181508  42911  32767        0x10          0    0  syz-executor
*421715  28937      0           0          0    1K sshd
db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438
panic(ffffffff835214b5) at panic+0x1e5 sys/kern/subr_prf.c:198
amap_pp_adjref(fffff1807080b5a0,0,2,1) at amap_pp_adjref+0x74c sys/uvm/uvm_amap.c:881
amap_adjref_anons(fffff1807080b5a0,0,2,1,0) at amap_adjref_anons+0x22d sys/uvm/uvm_amap.c:1299
uvm_mapent_clone(fffff1806cec6030,4e35bda6000,2000,0,3,7,6c2557755d07e1f2,fffff1806e3f8e90,ffff80002a2823e8,fffff1806cec6030) at uvm_mapent_clone+0x17e sys/uvm/uvm_map.c:3503
uvm_mapent_forkcopy(1,fffff1806cec6030,fffff1800b1f77a0,fffff1806e3f8e90,ffff80002a2823e8) at uvm_mapent_forkcopy+0x6f sys/uvm/uvm_map.c:3573
uvmspace_fork(ffff800045ff2690) at uvmspace_fork+0x299 sys/uvm/uvm_map.c:3776
process_new(ffff80003bfb87e8,ffff800045ff2690,1) at process_new+0x583 sys/kern/kern_fork.c:282
fork1(ffff80002a2222a8,1,ffffffff81462b20,0,ffff80002a2825c0,0) at fork1+0x3f6 sys/kern/kern_fork.c:-1
syscall(ffff80002a282670) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80002a282670) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7bcc1998ede0, count: 4
https://www.openbsd.org/ddb.html describes the minimum info required in bug
reports.  Insufficient info makes it difficult to find and fix bugs.
ddb{1}> 
ddb{1}> set $lines = 0
ddb{1}> set $maxwidth = 0
ddb{1}> show panic
*cpu1: amap_pp_adjref: negative reference count
ddb{1}> show kasan
No such command
ddb{1}> trace
db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438
panic(ffffffff835214b5) at panic+0x1e5 sys/kern/subr_prf.c:198
amap_pp_adjref(fffff1807080b5a0,0,2,1) at amap_pp_adjref+0x74c sys/uvm/uvm_amap.c:881
amap_adjref_anons(fffff1807080b5a0,0,2,1,0) at amap_adjref_anons+0x22d sys/uvm/uvm_amap.c:1299
uvm_mapent_clone(fffff1806cec6030,4e35bda6000,2000,0,3,7,6c2557755d07e1f2,fffff1806e3f8e90,ffff80002a2823e8,fffff1806cec6030) at uvm_mapent_clone+0x17e sys/uvm/uvm_map.c:3503
uvm_mapent_forkcopy(1,fffff1806cec6030,fffff1800b1f77a0,fffff1806e3f8e90,ffff80002a2823e8) at uvm_mapent_forkcopy+0x6f sys/uvm/uvm_map.c:3573
uvmspace_fork(ffff800045ff2690) at uvmspace_fork+0x299 sys/uvm/uvm_map.c:3776
process_new(ffff80003bfb87e8,ffff800045ff2690,1) at process_new+0x583 sys/kern/kern_fork.c:282
fork1(ffff80002a2222a8,1,ffffffff81462b20,0,ffff80002a2825c0,0) at fork1+0x3f6 sys/kern/kern_fork.c:-1
syscall(ffff80002a282670) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80002a282670) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7bcc1998ede0, count: -11
ddb{1}> show registers
rdi                                0
rsi                              0x1
rbp               0xffff80002a2820b0
rbx               0xffff80002999ee07
rdx                                0
rcx               0xffff80002a2222a8
rax               0xffff80002999dff0
r8                 0x101010101010101
r9                0x8080808080808080
r10               0xcfbf562797cf8e72
r11               0xa951d102f6833c7f
r12               0xffff80002999ec08
r13                                0
r14                                0
r15                              0x1
rip               0xffffffff83265d25    db_enter+0x25
cs                               0x8
rflags                         0x246
rsp               0xffff80002a2820a0
ss                              0x10
db_enter+0x25:  addq    $0x8,%rsp
ddb{1}> show proc
PROC (sshd) tid=421715 pid=28937 tcnt=1 stat=onproc
    flags process=0 proc=0
    runpri=50, usrpri=86, slppri=24, nice=20
    wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0
    forw=0xffffffffffffffff, list=0xffff80002a223c98,0xffff800045ffca78
    process=0xffff800045ff2690 user=0xffff80002a27d000, vmspace=0xfffff1800b1f77a0
    estcpu=36, cpticks=16559, pctcpu=0.0, user=0, sys=16559, intr=0
ddb{1}> ps
   PID     TID   PPID   UID  S      PRLAGS     PFLAGS WAIT      COMMAND
 30629  131443  22463 32767  2        0x10          0           syz-executor
 30629  306102  22463 32767  3        0x10  0x4000080 sbwait    syz-executor
 42911  181508  39968 32767  7        0x10          0           syz-executor
 42911  131200  39968 32767  2        0x10  0x4000080           syz-executor
 37072  426183   5536 32767  2        0x10          0           syz-executor
 37072   87492   5536 32767  3        0x10  0x4000080 fsleep    syz-executor
 37072  206196   5536 32767  3        0x10  0x4000080 fsleep    syz-executor
  9429  349083  55141 32767  2        0x10          0           syz-executor
  9429  298839  55141 32767  3        0x10  0x4000080 sbwait    syz-executor
  7389  207915  25166 32767  2        0x10          0           syz-executor
  7389  212775  25166 32767  3        0x10  0x4000080 fsleep    syz-executor
  7389    5299  25166 32767  3        0x10  0x4000080 fsleep    syz-executor
 36615  343143    576 32767  3        0x10       0x80 nanoslp   syz-executor
 36615  352954    576 32767  3        0x10  0x4000080 ttyout    syz-executor
 36615   34026    576 32767  3        0x10  0x4000080 fsleep    syz-executor
  3301   60921  22286 32767  3        0x10       0x80 nanoslp   syz-executor
  3301   50774  22286 32767  3        0x10  0x4000080 semwait   syz-executor
  3301  251752  22286 32767  3        0x10  0x4000080 fsleep    syz-executor
 45561  411835  94321 32767  3        0x10       0x80 nanoslp   syz-executor
 45561  417427  94321 32767  3        0x10  0x4000080 msgwait   syz-executor
 45561  149265  94321 32767  3        0x10  0x4000080 fsleep    syz-executor
 39968  368166  43690 32767  3        0x10       0x80 nanoslp   syz-executor
  5536  301182  39314 32767  3        0x10       0x80 nanoslp   syz-executor
 94321  174761  21002 32767  3        0x10       0x80 nanoslp   syz-executor
 22286  151885  18569 32767  3        0x10       0x80 nanoslp   syz-executor
 55141   70588   2440 32767  3        0x10       0x80 nanoslp   syz-executor
 25166  168747  64833 32767  3        0x10       0x80 nanoslp   syz-executor
 22463  110767  85370 32767  3        0x10       0x80 nanoslp   syz-executor
   576  200602  82280 32767  3        0x10       0x80 nanoslp   syz-executor
 18569   77183   5615     0  3         0x2       0x80 wait      syz-executor
 21002   29774   5615     0  3         0x2       0x80 wait      syz-executor
 43690  321925   5615     0  3         0x2       0x80 wait      syz-executor
 39314  129450   5615     0  3         0x2       0x80 wait      syz-executor
 85370  274396   5615     0  3         0x2       0x80 wait      syz-executor
  2440  130487   5615     0  3         0x2       0x80 wait      syz-executor
 64833  449566   5615     0  3         0x2       0x80 wait      syz-executor
 82280  523895   5615     0  3         0x2       0x80 wait      syz-executor
  5615  319360  75456     0  3         0x2       0x80 kqread    syz-executor
 75456  348453  27214     0  3    0x100002       0x88 sigsusp   ksh
 27214  342092   4938     0  3        0x10       0x88 kqread    sshd-session
  4938  219894  28937     0  3        0x12       0x80 kqread    sshd-session
 22639  125826      1     0  3    0x100003       0x80 ttyin     getty
*28937  421715      1     0  7           0          0           sshd
 79863   26227  86224    73  3   0x1100010       0x80 kqread    syslogd
 86224  142427      1     0  3    0x100002       0x80 sbwait    syslogd
 19525  195736      1     0  3    0x100000       0x80 kqread    resolvd
 98914  417079  62104    77  3    0x100012       0x80 kqread    dhcpleased
 63543  164777  62104    77  3    0x100012       0x80 kqread    dhcpleased
 62104  158235      1     0  3           0       0x80 kqread    dhcpleased
 95776  506920      0     0  3     0x14000      0x200 bored     smr
 62281  169995      0     0  2     0x14000      0x200           zerothread
 10101   40300      0     0  3     0x14000      0x200 aiodoned  aiodoned
 14896  449567      0     0  3     0x14000      0x200 syncer    update
 97570  325183      0     0  3     0x14000      0x200 cleaner   cleaner
 13202  240632      0     0  3     0x14000      0x200 reaper    reaper
 51824  518255      0     0  3     0x14000      0x200 pgdaemon  pagedaemon
 15015  448043      0     0  3     0x14000      0x200 bored     viomb
 29783  366601      0     0  3     0x14000 0x40000200 acpi0     acpi0
 96160  282407      0     0  3     0x14000 0x40000200           idle1
 71638  184500      0     0  3     0x14000      0x200 bored     softnet1
 56155  148440      0     0  2     0x14000      0x200           softnet0
 83502  372304      0     0  3     0x14000      0x200 bored     systqmp
 12520  475557      0     0  3     0x14000      0x200 bored     systq
 35204  423259      0     0  3     0x14000      0x200 tmoslp    softclockmp
 51566  344455      0     0  3     0x14000 0x40000200 tmoslp    softclock
 39886  470124      0     0  3     0x14000 0x40000200           idle0
     1   83497      0     0  3         0x2       0x80 wait      init
     0       0     -1     0  3     0x10000      0x200 scheduler swapper
ddb{1}> show all locks
Process 28937 (sshd) thread 0xffff80002a2222a8 (421715)
exclusive rwlock amaplk r = 0 (0xfffff1806f2c7148)
#0  witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline]
#0  witness_lock+0x5f1 sys/kern/subr_witness.c:1160
#1  rw_do_enter_write+0x419 sys/kern/kern_rwlock.c:320
#2  amap_ref+0x3c sys/uvm/uvm_amap.c:1313
#3  uvm_mapent_clone+0x17e sys/uvm/uvm_map.c:3503
#4  uvm_mapent_forkcopy+0x6f sys/uvm/uvm_map.c:3573
#5  uvmspace_fork+0x299 sys/uvm/uvm_map.c:3776
#6  process_new+0x583 sys/kern/kern_fork.c:282
#7  fork1+0x3f6 sys/kern/kern_fork.c:-1
#8  syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
#8  syscall+0xb17 sys/arch/amd64/amd64/trap.c:783
#9  Xsyscall+0x128
exclusive rwlock vmmaplk r = 0 (0xfffff1806cec6130)
#0  witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline]
#0  witness_lock+0x5f1 sys/kern/subr_witness.c:1160
#1  rw_do_enter_write+0x419 sys/kern/kern_rwlock.c:320
#2  vm_map_lock_ln+0x12e sys/uvm/uvm_map.c:5170
#3  uvmspace_fork+0x12b sys/uvm/uvm_map.c:3752
#4  process_new+0x583 sys/kern/kern_fork.c:282
#5  fork1+0x3f6 sys/kern/kern_fork.c:-1
#6  syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
#6  syscall+0xb17 sys/arch/amd64/amd64/trap.c:783
#7  Xsyscall+0x128
exclusive rwlock vmmaplk r = 0 (0xfffff1800b1f78a0)
#0  witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline]
#0  witness_lock+0x5f1 sys/kern/subr_witness.c:1160
#1  rw_do_enter_write+0x419 sys/kern/kern_rwlock.c:320
#2  vm_map_lock_ln+0x12e sys/uvm/uvm_map.c:5170
#3  uvmspace_fork+0x44 sys/uvm/uvm_map.c:3743
#4  process_new+0x583 sys/kern/kern_fork.c:282
#5  fork1+0x3f6 sys/kern/kern_fork.c:-1
#6  syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
#6  syscall+0xb17 sys/arch/amd64/amd64/trap.c:783
#7  Xsyscall+0x128
exclusive kernel_lock &kernel_lock r = 0 (0xffffffff839e2bc0)
#0  witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline]
#0  witness_lock+0x5f1 sys/kern/subr_witness.c:1160
#1  syscall+0xaf4 mi_syscall sys/sys/syscall_mi.h:175 [inline]
#1  syscall+0xaf4 sys/arch/amd64/amd64/trap.c:783
#2  Xsyscall+0x128
ddb{1}> show malloc
           Type InUse  MemUse  HighUse   Limit  Requests Type Lim
         devbuf 11051  12018K   12034K 166960K     12142        0
            pcb    17     12K      12K 166960K        17        0
         rtable   243      6K       7K 166960K       391        0
             pf    31     16K      16K 166960K        31        0
         ifaddr    42      7K       7K 166960K        44        0
        ifgroup    50      2K       2K 166960K        50        0
         sysctl     1      1K       9K 166960K         6        0
       counters    70     37K      37K 166960K        70        0
       ioctlops     0      0K       2K 166960K        32        0
            iov     0      0K      16K 166960K         3        0
          mount     1      1K       1K 166960K         1        0
            log     0      0K       0K 166960K         4        0
         vnodes  1287     81K      81K 166960K      1357        0
      UFS quota     1     32K      32K 166960K         1        0
      UFS mount     5     36K      36K 166960K         5        0
            shm     2      1K       9K 166960K         6        0
         VM map     2      1K       1K 166960K         2        0
            sem     5      0K       0K 166960K         5        0
        dirhash    12      2K       2K 166960K        15        0
           ACPI  1734    201K     291K 166960K     11964        0
      file desc    26     97K     125K 166960K       216        0
           proc    58     99K     163K 166960K       505        0
        subproc    72      4K       4K 166960K        72        0
    NFS srvsock     1      0K       0K 166960K         1        0
     NFS daemon     1     16K      16K 166960K         1        0
    ip_moptions     0      0K       0K 166960K        12        0
       in_multi    99      7K       7K 166960K       100        0
    ether_multi     1      0K       0K 166960K         1        0
            mrt     0      0K       0K 166960K         3        0
    ISOFS mount     1     32K      32K 166960K         1        0
  MSDOSFS mount     1     16K      16K 166960K         1        0
           ttys    67    307K     307K 166960K        67        0
           exec     0      0K       1K 166960K       364        0
   fusefs mount     1     32K      32K 166960K         1        0
            tdb     3      0K       0K 166960K         3        0
        VM swap     8     62K      64K 166960K        10        0
       UVM amap   267    161K     176K 166960K      3532        0
       UVM aobj     8      2K       2K 166960K         9        0
     pinsyscall    49     98K     111K 166960K      1288        0
        memdesc     1      4K       4K 166960K         1        0
    crypto data     1      1K       1K 166960K         1        0
    ip6_options     0      0K       0K 166960K         4        0
            NDP    13      0K       2K 166960K        27        0
           temp    37   9118K    9120K 166960K      3824        0
         kqueue    13     20K      28K 166960K        41        0
      SYN cache     2     16K      16K 166960K         2        0
ddb{1}> show all pools
Name      Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle
plcache    128       28    0        0     1     0     1     1     0     8    0
rtpcb      120       44    0       41     1     0     1     1     0     8    0
rtentry    176      114    0        1     6     0     6     6     0     8    0
unpcb      144       80    0       59     1     0     1     1     0     8    0
syncache   336        5    0        5     1     0     1     1     0     8    1
tcpcb      736       36    0       30     1     0     1     1     0     8    0
arp        136       18    0        0     1     0     1     1     0     8    0
inpcb      328      140    0      126     2     0     2     2     0     8    0
nd6        152       27    0        0     2     0     2     2     0     8    0
kcovpl      48        8    0        0     1     0     1     1     0     8    0
art_heap8  4096       1    0        0     1     0     1     1     0     8    0
art_heap4  256      472    0        0    30     0    30    30     0     8    0
art_table   40      473    0        0     5     0     5     5     0     8    0
art_node    32      114    0       11     1     0     1     1     0     8    0
sysvmsgpl   40        1    0        0     1     0     1     1     0     8    0
semapl      72        3    0        0     1     0     1     1     0     8    0
shmpl      112        6    0        1     1     0     1     1     0     8    0
dirhash    1024      19    0        2     3     0     3     3     0     8    0
dino2pl    256     1650    0      188    92     0    92    92     0     8    0
ffsino     296     1650    0      188   113     0   113   113     0     8    0
nchpl      144     1938    0      250    63     0    63    63     0     8    0
vnodes     216     1731    0        0    97     0    97    97     0     8    0
namei      1024    5779    0     5779     1     0     1     1     0     8    1
percpumem   16       51    0        0     1     0     1     1     0     8    0
kstatmem   264       25    0        0     2     0     2     2     0     8    0
scxspl     216     6579    0     6579     4     2     2     3     1     8    2
plimitpl   152       40    0       16     1     0     1     1     0     8    0
sigapl     424      506    0      451     7     0     7     7     0     8    0
knotepl    120      100    0        0     4     0     4     4     0     8    0
kqueuepl   224       43    0       33     1     0     1     1     0     8    0
pipepl     344      128    0      100     3     0     3     3     0     8    0
fdescpl    528      490    0      451     4     0     4     4     0     8    0
filepl     160     1891    0     1669    10     0    10    10     0     8    0
lockfpl    104       25    0       23     1     0     1     1     0     8    0
lockfspl    48       11    0        9     1     0     1     1     0     8    0
sessionpl  144       28    0       12     1     0     1     1     0     8    0
pgrppl      48       37    0       13     1     0     1     1     0     8    0
ucredpl    104      188    0      169     1     0     1     1     0     8    0
zombiepl   144      451    0      451     1     0     1     1     0     8    1
processpl  1232     506    0      451     5     0     5     5     0     8    0
procpl     664      618    0      550     6     0     6     6     0     8    0
sockpl     752      265    0      226     5     0     5     5     0     8    1
mcl64k     65536      2    0        0     1     0     1     1     0     8    0
mcl16k     16384      1    0        0     1     0     1     1     0     8    0
mcl8k      8192       3    0        0     1     0     1     1     0     8    0
mcl4k      4096     116    0        0    15     0    15    15     0     8    0
mcl2k2     2112       2    0        0     1     0     1     1     0     8    0
mcl2k      2048      24    0        0     3     0     3     3     0     8    0
mextrefs    64       20    0        0     1     0     1     1     0     8    0
mtagpl      96        3    0        0     1     0     1     1     0     8    0
mbufpl     256      199    0        0    13     0    13    13     0     8    0
bufpl      272     2315    0      102   148     0   148   148     0     8    0
anonpl      32     5443    0        0    44     0    44    44     0   247    0
amapchunkpl 152   11001    0    10261    38     0    38    38     0   158    9
amappl16   200     1526    0     1503     5     0     5     5     0     8    3
amappl15   192        4    0        3     1     0     1     1     0     8    0
amappl14   184      400    0      399     1     0     1     1     0     8    0
amappl13   176      114    0      104     1     0     1     1     0     8    0
amappl12   168      718    0      681     2     0     2     2     0     8    0
amappl11   160        7    0        7     1     0     1     1     0     8    1
amappl10   152       57    0       47     1     0     1     1     0     8    0
amappl9    144      300    0      300     1     0     1     1     0     8    1
amappl8    136      141    0      140     1     0     1     1     0     8    0
amappl7    128      134    0      123     1     0     1     1     0     8    0
amappl6    120      151    0      149     1     0     1     1     0     8    0
amappl5    112       96    0       88     1     0     1     1     0     8    0
amappl4    104      259    0      243     1     0     1     1     0     8    0
amappl3     96     1851    0     1707     5     1     4     4     0     8    0
amappl2     88      506    0      453     2     0     2     2     0     8    0
amappl1     80    10289    0     9717    14     0    14    14     0     8    1
amappl      88     2864    0     2660     5     0     5     5     0    92    0
uvmvnodes   80       95    0        0     2     0     2     2     0     8    0
dma4096    4096       1    0        1     1     1     0     1     0     8    0
dma1024    1024       1    0        0     1     0     1     1     0     8    0
dma256     256        6    0        6     1     1     0     1     0     8    0
dma128     128      253    0      253     1     1     0     1     0     8    0
dma64       64        6    0        6     1     1     0     1     0     8    0
dma32       32        7    0        7     1     1     0     1     0     8    0
dma16       16       18    0       17     1     0     1     1     0     8    0
aobjpl      72        8    0        1     1     0     1     1     0     8    0
uaddrrnd    24      490    0      451     1     0     1     1     0     8    0
uaddrbest   32        2    0        0     1     0     1     1     0     8    0
uaddr       24      490    0      451     1     0     1     1     0     8    0
vmmpekpl   168     5749    0     5715     2     0     2     2     0     8    0
vmmpepl    168    39669    0    37507    94     0    94    94     0   357    0
vmsppl     488      489    0      451     7     1     6     6     0     8    0
rwobjpl     80    14378    0    13413    22     0    22    22     0     8    0
pdppl      4096     987    0      902   107    20    87    97     0     8    2
pvpl        32    13101    0        0   106     0   106   106     0   265    0
pmappl     256      489    0      451     4     1     3     3     0     8    0
extentpl    40       46    0       28     1     0     1     1     0     8    0
phpool     112      425    0       23    12     0    12    12     0     8    0
ddb{1}> machine ddbcpu 0
Stopped at      x86_ipi_db+0x27:        addq    $0x8,%rsp
x86_ipi_db(ffffffff838f6ff0) at x86_ipi_db+0x27 sys/arch/amd64/amd64/db_interface.c:394
x86_ipi_handler() at x86_ipi_handler+0xd9 sys/arch/amd64/amd64/ipi.c:106
Xresume_lapic_ipi() at Xresume_lapic_ipi+0x27
__mp_lock(ffffffff839e23c0) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:142 [inline]
__mp_lock(ffffffff839e23c0) at __mp_lock+0x192 sys/kern/kern_lock.c:173
softintr_dispatch(0) at softintr_dispatch+0x125 sys/kern/kern_softintr.c:83
dosoftint(0) at dosoftint+0x54 sys/arch/amd64/amd64/intr.c:862
Xsoftclock() at Xsoftclock+0x27
end of kernel
end trace frame: 0x7740f2fa1a40, count: 8
ddb{0}> trace
x86_ipi_db(ffffffff838f6ff0) at x86_ipi_db+0x27 sys/arch/amd64/amd64/db_interface.c:394
x86_ipi_handler() at x86_ipi_handler+0xd9 sys/arch/amd64/amd64/ipi.c:106
Xresume_lapic_ipi() at Xresume_lapic_ipi+0x27
__mp_lock(ffffffff839e23c0) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:142 [inline]
__mp_lock(ffffffff839e23c0) at __mp_lock+0x192 sys/kern/kern_lock.c:173
softintr_dispatch(0) at softintr_dispatch+0x125 sys/kern/kern_softintr.c:83
dosoftint(0) at dosoftint+0x54 sys/arch/amd64/amd64/intr.c:862
Xsoftclock() at Xsoftclock+0x27
end of kernel
end trace frame: 0x7740f2fa1a40, count: -7
ddb{0}> machine ddbcpu 1
Stopped at      db_enter+0x25:  addq    $0x8,%rsp
db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438
panic(ffffffff835214b5) at panic+0x1e5 sys/kern/subr_prf.c:198
amap_pp_adjref(fffff1807080b5a0,0,2,1) at amap_pp_adjref+0x74c sys/uvm/uvm_amap.c:881
amap_adjref_anons(fffff1807080b5a0,0,2,1,0) at amap_adjref_anons+0x22d sys/uvm/uvm_amap.c:1299
uvm_mapent_clone(fffff1806cec6030,4e35bda6000,2000,0,3,7,6c2557755d07e1f2,fffff1806e3f8e90,ffff80002a2823e8,fffff1806cec6030) at uvm_mapent_clone+0x17e sys/uvm/uvm_map.c:3503
uvm_mapent_forkcopy(1,fffff1806cec6030,fffff1800b1f77a0,fffff1806e3f8e90,ffff80002a2823e8) at uvm_mapent_forkcopy+0x6f sys/uvm/uvm_map.c:3573
uvmspace_fork(ffff800045ff2690) at uvmspace_fork+0x299 sys/uvm/uvm_map.c:3776
process_new(ffff80003bfb87e8,ffff800045ff2690,1) at process_new+0x583 sys/kern/kern_fork.c:282
fork1(ffff80002a2222a8,1,ffffffff81462b20,0,ffff80002a2825c0,0) at fork1+0x3f6 sys/kern/kern_fork.c:-1
syscall(ffff80002a282670) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80002a282670) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7bcc1998ede0, count: 4
ddb{1}> trace
db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438
panic(ffffffff835214b5) at panic+0x1e5 sys/kern/subr_prf.c:198
amap_pp_adjref(fffff1807080b5a0,0,2,1) at amap_pp_adjref+0x74c sys/uvm/uvm_amap.c:881
amap_adjref_anons(fffff1807080b5a0,0,2,1,0) at amap_adjref_anons+0x22d sys/uvm/uvm_amap.c:1299
uvm_mapent_clone(fffff1806cec6030,4e35bda6000,2000,0,3,7,6c2557755d07e1f2,fffff1806e3f8e90,ffff80002a2823e8,fffff1806cec6030) at uvm_mapent_clone+0x17e sys/uvm/uvm_map.c:3503
uvm_mapent_forkcopy(1,fffff1806cec6030,fffff1800b1f77a0,fffff1806e3f8e90,ffff80002a2823e8) at uvm_mapent_forkcopy+0x6f sys/uvm/uvm_map.c:3573
uvmspace_fork(ffff800045ff2690) at uvmspace_fork+0x299 sys/uvm/uvm_map.c:3776
process_new(ffff80003bfb87e8,ffff800045ff2690,1) at process_new+0x583 sys/kern/kern_fork.c:282
fork1(ffff80002a2222a8,1,ffffffff81462b20,0,ffff80002a2825c0,0) at fork1+0x3f6 sys/kern/kern_fork.c:-1
syscall(ffff80002a282670) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80002a282670) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7bcc1998ede0, count: -11

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/07/30 04:49 openbsd cc5b7dd097c6 2377cd3d .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-setuid panic: amap_pp_adjref: negative reference count
2026/07/29 02:57 openbsd 7c9a09f11f52 19622d9d .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-setuid panic: amap_pp_adjref: negative reference count
2026/07/22 08:09 openbsd e524649e2c66 b561ce9c .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-setuid panic: amap_pp_adjref: negative reference count
2026/07/20 00:10 openbsd 2fc221d2874b 72524a66 .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-setuid panic: amap_pp_adjref: negative reference count
2026/05/30 16:02 openbsd 1e1be23b32e7 cb4e87ff .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-setuid panic: amap_pp_adjref: negative reference count
* Struck through repros no longer work on HEAD.