kern/68442: panic - acquiring duplicate lock of same type: "sleepq chain"

[Daniel Lang]

The following reply was made to PR kern/68442; it has been noted by GNATS.

From: Daniel Lang <dl at leo.org>
To: freebsd-gnats-submit at FreeBSD.org, dl at leo.org
Cc:  
Subject: Re: kern/68442: panic - acquiring duplicate lock of same type: "sleepq chain"
Date: Mon, 28 Jun 2004 22:24:34 +0200

 Ok,
 
 the problem occurs also with:=20
 
 - non PAE kernel (use the same kernel config without the PAE
   part, which includes the other=20
 
 - completeley changed RAM, which was known to work before
   (I did a system upgrade in between)
 
 I could get some more data and a ddb stacktrace.
 
 I could not get gdb to analyse it, although I could obtain
 a dump, because /var was too full, so it was not saved. :(
 
 I usually get no ddb prompt and no crash dump, so this was
 a rare occasion :((
 
 Here is what I got:
 [..]
 
 login: lock order reversal
  1st 0x80746940 sio (sio) @ /usr/src/sys/dev/sio/sio.c:3220
  2nd 0x807105b4 sleepq chain (sleepq chain) @ /usr/src/sys/kern/subr_sleepq=
 ueue3
 Stack backtrace:
 backtrace(ffffffff,80713568,80713590,806e31a4,807365dc) at 0x8051e012 =3D b=
 acktra2
 witness_checkorder(807105b4,9,8069fdd9,c1,1310) at 0x80539428 =3D witness_c=
 heckor4
 _mtx_lock_spin_flags(807105b4,0,8069fdd9,c1,83fee000) at 0x80516e4a =3D _mt=
 x_locke
 sleepq_lookup(86ea7ad8,86ea7aa8,100,86ea7aa8,7d7) at 0x8053673a =3D sleepq_=
 lookupe
 msleep(86ea7ad8,86ea7aa8,158,806a2582,0) at 0x8052357a =3D msleep+0xa6
 sbwait(86ea7a94,0,1235,0,0) at 0x8054fbaf =3D sbwait+0x33
 do_sendfile(83f9b540,ab0a9d14,0,ab0a9d40,80665343) at 0x80553afd =3D do_sen=
 dfile+5
 sendfile(83f9b540,ab0a9d14,8,a9,202) at 0x80552e9c =3D sendfile+0x10
 syscall(2f,2f,7fbf002f,8,0) at 0x80665343 =3D syscall+0x217
 Xint0x80_syscall() at 0x8065467f =3D Xint0x80_syscall+0x1f
 --- syscall (393), eip =3D 0x2812123b, esp =3D 0x7fbfde4c, ebp =3D 0x7fbfde=
 a8 ---
 
 
 Fatal trap 12: page fault while in kernel mode
 cpuid =3D 1; apic id =3D 06
 fault virtual address   =3D 0x34
 fault code              =3D supervisor read, page not present
 instruction pointer     =3D 0x8:0x805390fa
 stack pointer           =3D 0x10:0xaae8eb1c
 frame pointer           =3D 0x10:0xaae8eb40
 code segment            =3D base 0x0, limit 0xfffff, type 0x1b
                         =3D DPL 0, pres 1, def32 1, gran 1
 processor eflags        =3D interrupt enabled, resume, IOPL =3D 0
 current process         =3D 6196 (ftpd)
 kernel: type 12 trap, code=3D0
 Stopped at      0x805390fa =3D witness_checkorder+0x176:  movl    0x34(%eax=
 ),%edx
 db>
 db> trace
 witness_checkorder(8071021c,9,8069fdd9,c1,f78) at 0x805390fa =3D witness_ch=
 eckord6
 _mtx_lock_spin_flags(8071021c,0,8069fdd9,c1,83e78e70) at 0x80516e4a =3D _mt=
 x_locke
 sleepq_lookup(87a86370,86a5a904,0,8069fdd9,145) at 0x8053673a =3D sleepq_lo=
 okup+0e
 sleepq_catch_signals(87a86370,0,100,0,806a2729) at 0x805369cd =3D sleepq_ca=
 tch_sid
 msleep(87a86370,87a86340,158,806a2582,0) at 0x80523707 =3D msleep+0x233
 sbwait(87a8632c,0,1ac6,0,0) at 0x8054fbaf =3D sbwait+0x33
 do_sendfile(83e78e70,aae8ed14,0,aae8ed40,80665343) at 0x80553afd =3D do_sen=
 dfile+5
 sendfile(83e78e70,aae8ed14,8,9,202) at 0x80552e9c =3D sendfile+0x10
 syscall(7fbf002f,7fbf002f,7fbf002f,7,0) at 0x80665343 =3D syscall+0x217
 Xint0x80_syscall() at 0x8065467f =3D Xint0x80_syscall+0x1f
 --- syscall (393, FreeBSD ELF32, sendfile), eip =3D 0x2812123b, esp =3D 0x7=
 fbfde4c,-
 
 
 Hope this helps.
 
 Cheers,
  Daniel
 --=20
 IRCnet: Mr-Spock   - signs of absurd developments in the net community:=20
 #42:   - "Wurstbrot gehoert m.E. zum Fruehstuecks-botnet von Cartoon" - =20
  Daniel Lang * dl at leo.org * +49 89 289 18532 * http://www.leo.org/~dl/