Subject: Re: i386 MP panic: amap_pp_adjref: negative reference count
To: Andrew Brown <atatat@atatdot.net>
From: Sami Kantoluoto <sami.kantoluoto@sjk-software.fi>
List: current-users
Date: 12/16/2002 13:53:45
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On Sun, Dec 15, 2002 at 12:17:00PM -0500, Andrew Brown wrote:
> >> >>I'm getting that panic (amap_pp_adjref: negative reference count) when
> >> >>building openoffice. It seems to be repeatable. I don't have ddb/trace
> >> >
> >> >i noticed this three days ago in a completely different context.
> >> >nevertheless, i have made a patch that addresses the problem.  it
> >>
> >> 	http://www.daemon.org/amap_pp_adjref.2.patch
> >
> >Did not help, thanks anyway. I should be able to test other patches quickly
> >(well, maybe not today) now.
> 
> hmm...that's no fun.
> 
> what does the traceback in ddb look like?  do you get a crash dump?

Traceback attached, and no crash dump.

> can you build a kernel with -g so that gdb can do full port-mortem
> debugging?

Sure.

Anything to do in ddb that can help? (I can do that immediately because I
haven't rebooted the machine yet)


     -sk

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db{0}> trace
cpu_Debugger(c162fe40,0,6,0,6) at cpu_Debugger+0x4
panic(c0590fc0,1,5,c031c73d,e4b49dd0) at panic+0xad
amap_pp_adjref(e4b49dd0,1,7,ffffffff,e5198948) at amap_pp_adjref+0x17d
amap_unref(e4b49dd0,1,7,0,e4b41340) at amap_unref+0x99
uvm_unmap_detach(e5198388,0,bfbfc000,e51dcd6c,e4b41340) at uvm_unmap_detach+0x56
uvm_unmap(e4b41260,0,bfbfc000,d2f,e29ccba8) at uvm_unmap+0x146
uvmspace_exec(e4ad0400,0,bfbfc000,e51dce08,0) at uvmspace_exec+0x72
sys_execve(e4ad0400,e51dcf80,e51dcf78,c03c2f87,e4ad0400) at sys_execve+0x37d
syscall_plain(ffff001f,bfbf001f,812001f,4824001f,812caa8) at syscall_plain+0xbc
db{0}> machine cpu
addr            dev     id      flags   ipis    curproc         fpcurproc
0xc06f4f60      cpu0    1       7009    0              0x0      0xe4a437e8
0xc1459800      cpu1    0       b002    0       0xe4ad0400             0x0
db{0}> ps
 PID             PPID       PGRP        UID S   FLAGS          COMMAND    WAIT
>22798          22758      11496          0 7 0x180006             idlc
 22758          22757      11496          0 3 0x84086             idlc  select
 22757          22686      11496          0 3 0x84086             tcsh   pause
 22686          23583      11496          0 3 0x84086            dmake    wait
 23583          23582      11496          0 3 0x84086             perl    wait
 23582          23581      11496          0 3 0x84086             tcsh   pause
 23581          14011      11496          0 3 0x84086            dmake    wait
 14011          14010      11496          0 3 0x84086             tcsh   pause
 14010          13997      11496          0 3 0x84086               sh    wait
 13997          13996      11496          0 3 0x84086             make    wait
 13996          11496      11496          0 3 0x84086               sh    wait
 11702              1      11702          0 3 0x84086            getty   ttyin
 11496            241      11496          0 3 0x85086             make    wait
 357                1        251          0 3 0x84086             Xvfb  select
 241              240        241          0 3 0x84086             bash    wait
 240                1        240          0 3 0x80085    screen-3.9.13  select
 230                1        230          0 3 0x84087             bash   ttyin
 229                1        229          0 3 0x84086            getty   ttyin
 228                1        228          0 3 0x84086            getty   ttyin
 227                1        227          0 3 0x84086            getty   ttyin
 224                1        224          0 3 0x80084             cron nanosle
 219                1        219          0 3 0x80084            inetd   pause
 205                1        205          0 3 0x80084             sshd  select
 189                1        189          0 3 0x80084             ntpd   pause
 178                1        178          0 3 0x80084              lpd  select
 138                0          0          0 3 0xa0284            nfsio  nfsidl
 137                0          0          0 3 0xa0284            nfsio  nfsidl
 136                0          0          0 3 0xa0284            nfsio  nfsidl
 135                0          0          0 3 0xa0284            nfsio  nfsidl
 111                1        111          0 3 0x80084          syslogd  select
 84                 1         84          0 3 0x80084         dhclient  select
 9                  0          0          0 3 0xa0204         aiodoned aiodone
 8                  0          0          0 3 0xa0204          ioflush  syncer
 7                  0          0          0 3 0x20204           reaper  reaper
 6                  0          0          0 3 0xa0204       pagedaemon pgdaemo
 5                  0          0          0 3 0xa0204             pms0 pmsrese
 4                  0          0          0 3 0xa0204          usbtask  usbtsk
 3                  0          0          0 3 0xa0204             usb0  usbevt
 2                  0          0          0 3 0xa0204        atapibus0  sccomp
 1                  0          1          0 3 0x84084             init    wait
 0                 -1          0          0 3 0xa0204          swapper schedul
db{0}> 

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