panic: Assertion td->td_turnstile != NULL failed

Stefan Farfeleder stefan at fafoe.narf.at
Sat Nov 15 10:21:03 PST 2003


Hi,

this panic just happened on an i386 SMP box that was idle except for
generating tons of "checking stopevent 2 with the following
non-sleepable locks held" messages.  Its sources are are just a few
hours old.

%%
checking stopevent 2 with the following non-sleepable locks held:               
exclusive sleep mutex sigacts r = 0 (0xc6b6caa8) locked @ /freebsd/frog/src/sys/kern/subr_trap.c:260
panic: Assertion td->td_turnstile != NULL failed at /freebsd/frog/src/sys/kern/subr_turnstile.c:437
cpuid = 0;                                                                      
Debugger("panic")                                                               
Stopped at      Debugger+0x4e:  xchgl   %ebx,in_Debugger.0                      
db> t                                                                           
Debugger(c070b63e,0,c070ab4a,e041ca58,100) at Debugger+0x4e
panic(c070ab4a,c070e631,c070e401,1b5,c0793a40) at panic+0x148
turnstile_wait(c6938240,c078f4a0,c68bc140,1cc,c078f4a0) at turnstile_wait+0x29c
_mtx_lock_sleep(c078f4a0,0,c0723748,df,c29a8b04) at _mtx_lock_sleep+0x111
_mtx_lock_flags(c078f4a0,0,c0723748,df,bf800000) at _mtx_lock_flags+0x98
vm_fault(c078be80,0,2,8,c29a9780) at vm_fault+0x5a
trap_pfault(e041cc2c,0,0,e041cc1c,0) at trap_pfault+0xf6
trap(18,10,10,0,e041cca8) at trap+0x2f3
calltrap() at calltrap+0x5
--- trap 0xc, eip = 0xc06babb3, esp = 0xe041cc6c, ebp = 0xe041cc90 ---
intr_execute_handlers(c07782a4,e041cca8,e041ccec,c06ccc4e,7) at intr_execute_handlers+0x23
atpic_handle_intr(7) at atpic_handle_intr+0x41
Xatpic_intr7() at Xatpic_intr7+0x1e
--- interrupt, eip = 0xc06befe5, esp = 0xe041ccec, ebp = 0xe041ccec ---
cpu_idle_default(e041cd14,c0528bcc,c078f4a0,2,c07092f6) at cpu_idle_default+0x5
cpu_idle(c078f4a0,2,c07092f6,53,c0528b90) at cpu_idle+0x28
idle_proc(0,e041cd48,c070919e,311,0) at idle_proc+0x3c
fork_exit(c0528b90,0,e041cd48) at fork_exit+0xb4
fork_trampoline() at fork_trampoline+0x8
--- trap 0x1, eip = 0, esp = 0xe041cd7c, ebp = 0 ---
db> call doadump
Dumping 1023 MB
 16 32 48 64 80 96 112 128 144 160 176 192 208 224 240 256 272 288 304 320 336 352 368 384 400 416 432 448 464 480 496 512 528 544 560 576 592 608 624 640 656 672 688 704 720 736 752 768 784 800 816 832 848 864 880 896 912 928 944 960 976 992 1008
Dump complete
0xf
db> r
cpu_reset called on cpu#0
%%

GDB tells this:

%%
GNU gdb 5.2.1 (FreeBSD)
Copyright 2002 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "i386-undermydesk-freebsd"...
panic: Assertion td->td_turnstile != NULL failed at /freebsd/frog/src/sys/kern/subr_turnstile.c:437
panic messages:
---
panic: Assertion td->td_turnstile != NULL failed at /freebsd/frog/src/sys/kern/subr_turnstile.c:437
cpuid = 0; 
Dumping 1023 MB
 16 32 48 64 80 96 112 128 144 160 176 192 208 224 240 256 272 288 304 320 336 352 368 384 400 416 432 448 464 480 496 512 528 544 560 576 592 608 624 640 656 672 688 704 720 736 752 768 784 800 816 832 848 864 880 896 912 928 944 960 976 992 1008
---
#0  doadump () at /freebsd/frog/src/sys/kern/kern_shutdown.c:240
240		dumping++;
(kgdb) bt
#0  doadump () at /freebsd/frog/src/sys/kern/kern_shutdown.c:240
#1  0xc046ea8d in db_fncall (dummy1=1016, dummy2=0, dummy3=331, 
    dummy4=0xe041c894 "") at /freebsd/frog/src/sys/ddb/db_command.c:548
#2  0xc046e82a in db_command (last_cmdp=0xc077c140, cmd_table=0x0, 
    aux_cmd_tablep=0xc072fe2c, aux_cmd_tablep_end=0xc072fe30)
    at /freebsd/frog/src/sys/ddb/db_command.c:346
#3  0xc046e938 in db_command_loop ()
    at /freebsd/frog/src/sys/ddb/db_command.c:472
#4  0xc0471679 in db_trap (type=3, code=0)
    at /freebsd/frog/src/sys/ddb/db_trap.c:73
#5  0xc06b5343 in kdb_trap (type=3, code=0, regs=0xe041c9d4)
    at /freebsd/frog/src/sys/i386/i386/db_interface.c:171
#6  0xc06c9eae in trap (frame=
      {tf_fs = 24, tf_es = 16, tf_ds = 16, tf_edi = -1066357942, tf_esi = 1, tf_ebp = -532559328, tf_isp = -532559360, tf_ebx = 0, tf_edx = 0, tf_ecx = 1, tf_eax = 18, tf_trapno = 3, tf_err = 0, tf_eip = -1066707410, tf_cs = 8, tf_eflags = 134, tf_esp = -1066237866, tf_ss = -1066355138})
    at /freebsd/frog/src/sys/i386/i386/trap.c:580
#7  0xc06b6c48 in calltrap () at {standard input}:94
#8  0xc053cd18 in panic (fmt=0xc070ab4a "Assertion %s failed at %s:%d")
    at /freebsd/frog/src/sys/kern/kern_shutdown.c:534
#9  0xc0561a6c in turnstile_wait (ts=0xc6938240, lock=0xc078f4a0, 
    owner=0xc68bc140) at /freebsd/frog/src/sys/kern/subr_turnstile.c:469
---Type <return> to continue, or q <return> to quit---
#10 0xc05338a1 in _mtx_lock_sleep (m=0xc078f4a0, opts=0, 
    file=0xc0723748 "/freebsd/frog/src/sys/vm/vm_fault.c", line=223)
    at /freebsd/frog/src/sys/kern/kern_mutex.c:476
#11 0xc0533458 in _mtx_lock_flags (m=0xc078f4a0, opts=0, 
    file=0xc0723748 "/freebsd/frog/src/sys/vm/vm_fault.c", line=223)
    at /freebsd/frog/src/sys/kern/kern_mutex.c:218
#12 0xc067811a in vm_fault (map=0xc078be80, vaddr=0, fault_type=2 '\002', 
    fault_flags=8) at /freebsd/frog/src/sys/vm/vm_fault.c:223
#13 0xc06ca096 in trap_pfault (frame=0xe041cc2c, usermode=0, eva=0)
    at /freebsd/frog/src/sys/i386/i386/trap.c:711
#14 0xc06c9d33 in trap (frame=
      {tf_fs = 24, tf_es = 16, tf_ds = 16, tf_edi = 0, tf_esi = -532558680, tf_ebp = -532558704, tf_isp = -532558760, tf_ebx = -1030059368, tf_edx = 0, tf_ecx = 0, tf_eax = 1, tf_trapno = 12, tf_err = 2, tf_eip = -1066685517, tf_cs = 8, tf_eflags = 65538, tf_esp = -1030091636, tf_ss = -1068393691})
    at /freebsd/frog/src/sys/i386/i386/trap.c:420
#15 0xc06b6c48 in calltrap () at {standard input}:94
#16 0xc06cc9b1 in atpic_handle_intr (iframe=
      {if_vec = 7, if_fs = 24, if_es = 16, if_ds = 16, if_edi = 0, if_esi = -1030056064, if_ebp = -532558612, if_ebx = -1030059368, if_edx = -1065806176, if_ecx = 0, if_eax = 0, if_eip = -1066668059, if_cs = 8, if_eflags = 582, if_esp = -532558604, if_ss = -1066668008}) at /freebsd/frog/src/sys/i386/isa/atpic.c:335
#17 0xc06ccc4e in Xatpic_intr7 () at {standard input}:39
---Type <return> to continue, or q <return> to quit---
#18 0xc06bf018 in cpu_idle () at /freebsd/frog/src/sys/i386/i386/machdep.c:1071
#19 0xc0528bcc in idle_proc (dummy=0x0)
    at /freebsd/frog/src/sys/kern/kern_idle.c:86
#20 0xc05288d4 in fork_exit (callout=0xc0528b90 <idle_proc>, arg=0x0, 
    frame=0x0) at /freebsd/frog/src/sys/kern/kern_fork.c:793
(kgdb) f 9
#9  0xc0561a6c in turnstile_wait (ts=0xc6938240, lock=0xc078f4a0, 
    owner=0xc68bc140) at /freebsd/frog/src/sys/kern/subr_turnstile.c:469
469			MPASS(owner == ts->ts_owner);
(kgdb) l
464			else
465				TAILQ_INSERT_TAIL(&ts->ts_blocked, td, td_lockq);
466			mtx_unlock_spin(&td_contested_lock);
467			MPASS(td->td_turnstile != NULL);
468			LIST_INSERT_HEAD(&ts->ts_free, td->td_turnstile, ts_hash);
469			MPASS(owner == ts->ts_owner);
470		}
471	#ifdef INVARIANTS
472		td->td_turnstile = NULL;
473	#endif
(kgdb) p *td
$1 = {td_proc = 0xc29a8a98, td_ksegrp = 0xc29adc80, td_plist = {
    tqe_next = 0x0, tqe_prev = 0xc29a8aa8}, td_kglist = {tqe_next = 0x0, 
    tqe_prev = 0xc29adc9c}, td_slpq = {tqe_next = 0x0, tqe_prev = 0x0}, 
  td_lockq = {tqe_next = 0xc29aa640, tqe_prev = 0xc29aa160}, td_runq = {
    tqe_next = 0x0, tqe_prev = 0x0}, td_selq = {tqh_first = 0x0, 
    tqh_last = 0x0}, td_turnstile = 0x0, td_flags = 65568, td_inhibitors = 8, 
  td_pflags = 0, td_last_kse = 0xc29abe00, td_kse = 0xc29abe00, td_dupfd = 0, 
  td_wchan = 0x0, td_wmesg = 0x0, td_lastcpu = 0 '\0', td_oncpu = 0 '\0', 
  td_locks = 0, td_blocked = 0xc6938240, td_ithd = 0x0, 
  td_lockname = 0xc070ad83 "Giant", td_contested = {lh_first = 0x0}, 
  td_sleeplocks = 0x0, td_intr_nesting_level = 1, td_pinned = 0, 
  td_mailbox = 0x0, td_ucred = 0xc2996e80, td_standin = 0x0, td_prticks = 0, 
  td_upcall = 0x0, td_sticks = 9712, td_uuticks = 0, td_usticks = 0, 
  td_intrval = 0, td_oldsigmask = {__bits = {0, 0, 0, 0}}, td_sigmask = {
    __bits = {0, 0, 0, 0}}, td_siglist = {__bits = {0, 0, 0, 0}}, 
  td_waitset = 0x0, td_umtx = {tqe_next = 0x0, tqe_prev = 0x0}, 
  td_generation = 8792, td_base_pri = 160 ' ', td_priority = 68 'D', 
  td_pcb = 0xe041cda0, td_state = TDS_RUNNING, td_retval = {0, 0}, 
  td_slpcallout = {c_links = {sle = {sle_next = 0x0}, tqe = {tqe_next = 0x0, 
        tqe_prev = 0x0}}, c_time = 0, c_arg = 0x0, c_func = 0, c_flags = 8}, 
  td_frame = 0xe041cd48, td_kstack_obj = 0xc1032bdc, td_kstack = 3762401280, 
  td_kstack_pages = 2, td_altkstack_obj = 0x0, td_altkstack = 0, 
  td_altkstack_pages = 0, td_critnest = 1, td_md = {md_savecrit = 582}, 
---Type <return> to continue, or q <return> to quit---
  td_sched = 0xc29a98b8}
%%

Stefan


More information about the freebsd-current mailing list