LOR in schedcpu(), sched_4bsd.c

Sun Oct 5 08:58:05 PDT 2003

With today's CURRENT:

...
GEOM: create disk ad0 dp=0xc2a3a380
ad0: 38166MB <ST340016A> [77545/16/63] at ata0-master UDMA100
acd0: DVDROM <_NEC DV-5700B> at ata1-master UDMA33
Mounting root from ufs:/dev/ad0s1a
Loading configuration files.
Entropy harvesting: interrupts ethernet point_to_point.
Reseed type 1
Reseed finish
lock order reversal
 1st 0xc06bfa20 callout_dont_sleep (callout_dont_sleep) @ kern/kern_timeout.c:223
 2nd 0xc06bed80 allproc /sched_4bsd.c:253
Stack backtrace:
backtrace(c06537e4,c06bed80,c065018e,c065018e,c0651c30) at backtrace+0x17
witness_lock(c06bed80,0,c0651c30,fd,c06c1e60) at witness_lock+0x697
_sx_slock(c06bed80,c0651c27,fd,8,c0651945) at _sx_slock+0xa9
schedcpu(0,0,c065193c,df,c12a8ab0) at schedcpu+0x3f
softclock(0,0,c064e447,230,c12a77d0) at softclock+0x1fb
ithread_loop(c129d200,cdb17d48,c064e2c1,314,c70000e8) at ithread_loop+0x182
fork_exit(c04aa4a0,c129d200,cdb17d48) at fork_exit+0xc1
fork_trampoline() at fork_trampoline+0x8
--- trap 0x1, eip = 0, esp = 0xcdb17d7c, ebp = 0 ---
Debugger("witness_lock")
Stopped at      Debugger+0x54:  xchgl   %ebx,in_Debugger.0
db> show locks
exclusive sleep mutex callout_dont_sleep r = 0 (0xc06bfa20) locked @ kern/kern_timeout.c:223
db> show witness
Sleep locks:
0 taskqueue kthread -- last acquired @ kern/subr_taskqueue.c:253
0 g_xdown -- last acquired @ geom/geom_io.c:351
1  ATA disk bioqueue lock -- last acquired @ dev/ata/ata-disk.c:240
3  bio queue -- last acquired @ geom/geom_io.c:64
5  Malloc Stats -- last acquired @ kern/kern_malloc.c:335
3  ATA queue lock -- last acquired @ dev/ata/ata-queue.c:174
8  UMA pcpu -- last acquired @ vm/uma_core.c:1726
9   KMAP ENTRY -- last acquired @ vm/uma_core.c:1744
9   UMA zone -- last acquired @ vm/uma_core.c:1744
0 g_xup -- last acquired @ geom/geom_io.c:370
2  Giant -- last acquired @ kern/kern_timeout.c:216
3   malloc -- last acquired @ cquired @ kern/subr_eventhandler.c:213
4    eventhandler list -- last acquired @ kern/kern_exit.c:210
3   vm object_list -- last acquired @ vm/vm_object.c:620
3   arc4_mtx -- last acquired @ libkern/arc4random.c:137
3   UMA lock -- last acquired @ vm/uma_core.c:802
3   filedesc structure -- last acquired @ kern/kern_descrip.c:1625
4    pipe mutex -- last acquired @ kern/sys_pipe.c:481
5     sigio lock -- last acquired @ kern/kern_descrip.c:587
6      process group -- last acquired @ kern/kern_fork.c:575
7       process lock -- last acquired @ kern/kern_prot.c:1821
8        struct pargs.ref -- last acquired @ kern/kern_proc.c:1077
8        sigacts -- last acquired @ kern/kern_sig.c:596
8        vnode interlock -- last acquired @ kern/vfs_subr.c:2176
9         Syncer mtx -- last acquired @ kern/vfs_subr.c:1663
9         vnode_free_list -- last acquired @ kern/vfs_subr.c:923
9         spechash -- last acquired @ kern/vfs_subr.c:1989
8        ktrace -- last acquired @ kern/kern_fork.c:601
8        session -- last acquired @ kern/kern_fork.c:584
9         uidinfo hash -- last acquired @ kern/kern_resource.c:878
10         sleep mtxpool -- last acquired @ kern/kern_prot.c:1685
10         uidinfo struct -- last acquired @ order list:0
11          allprison -- last acquired @ order list:0
3   ithread -- last acquired @ kern/kern_intr.c:265
3   GEOM orphanage -- last acquired @ geom/geom_event.c:169
3   rman head -- last acquired @ kern/subr_rman.c:110
3   sf_bufs list lock -- last acquired @ i386/i386/vm_machdep.c:577
5    Malloc Stats -- (already displayed)
5    system map -- last acquired @ vm/vm_map.c:2904
6     kmem object -- last acquired @ vm/vm_kern.c:437
7      vm page queue mutex -- last acquired @ vm/vm_object.c:594
8       vnode interlock -- (already displayed)
8       UMA pcpu -- (already displayed)
7      CMAPCADDR12 -- last acquired @ i386/i386/pmap.c:2475
6     vm object -- last acquired @ vm/vm_object.c:433
7      vm page queue mutex -- (already displayed)
7      CMAPCADDR12 -- (already displayed)
3   taskqueue list -- last acquired @ kern/subr_taskqueue.c:384
3   kernel linker -- last acquire/kern_linker.c:460
3   rman -- last acquired @ kern/subr_rman.c:132
5    Malloc Stats -- (already displayed)
5    system map -- (already displayed)
3   sellck -- last acquired @ kern/sys_generic.c:1174
3   domain list -- last acquired @ kern/uipc_domain.c:114
3   devd -- last acquired @ kern/subr_bus.c:406
3   callout_dont_sleep -- last acquired @ kern/kern_timeout.c:223
4    ifnet -- last acquired @ net/if.c:1172
4    tcp -- last acquired @ netinet/tcp_timer.c:141
4    ipflow list head -- last acquired @ netinet/ip_flow.c:288
4    ipqlock -- last acquired @ netinet/ip_input.c:1237
4    mbuf PCPU list lock -- last acquired @ kern/subr_mbuf.c:926
5     mbuf subsystem general lists lock -- last acquired @ kern/subr_mbuf.c:676
3   vm86 lock -- last acquired @ i386/i386/vm86.c:606
3   ATA queue lock -- (already displayed)
3   mntvnode vfs_subr.c:1054
3   pseudofs -- last acquired @ fs/pseudofs/pseudofs_fileno.c:86
3   bpf global lock -- last acquired @ net/bpf.c:1383
3   IPFW static rules -- last acquired @ netinet/ip_fw2.c:2159
3   random reseed -- last acquired @ dev/random/yarrow.c:172
3   mntid -- last acquired @ kern/vfs_subr.c:586
4    mountlist -- last acquired @ kern/vfs_mount.c:774
3   bio queue -- (already displayed)
3   pbuf mutex -- last acquired @ vm/vm_pager.c:443
3   devstat -- last acquired @ kern/subr_devstat.c:83
3   radix node head -- last acquired @ net/route.c:544
4    rtentry -- last acquired @ netinet6/nd6_rtr.c:1502
5     Malloc Stats -- (already displayed)
5     ifaddr -- last acquired @ net/route.c:670
5     system map -- (already displayed)
4    ifnet -- (already displayed)
3   buffer daemon lock -- last acquired @ kern/vfs_bio.c:2103
3   needsbuffer lock -- last acquired @ kern/vfs_bio.c:291
3   ufs ihash -- last acquired @ ufs/ufs/ufs_ihash.c:160
8    vnode interlock -- (already displayed)
3   bdone lock -- last acquired @ kern/vfs_bio.c:3747
3   p_peers -- last acquired @ kern/kern_exit.c:252
3   runningbufspace lock -- last acquired @ kern/vfs_bio.c:309
3   buf queue lock -- last acquired @ kern/vfs_bio.c:1387
8    vnode interlock -- (already displayed)
3   pseudofs_vncache -- last acquired @ fs/pseudofs/pseudofs_vncache.c:225
3   sem -- last acquired @ kern/sysv_sem.c:1158
3   accounting -- last acquired @ kern/kern_acct.c:232
3   fdesc -- last acquired @ kern/kern_descrip.c:1515
0 g_disk_done -- last acquired @ geom/geom_disk.c:183
3  bio queue -- (already displayed)
8  UMA pcpu -- (already displayed)
0 taskqueue -- last acquired @ kern/subr_taskqueue.c:210
0 GEOM event stalling -- last acquired @ geom/geom_event.c:157
1  GEOM topology -- last acquired @ geom/geom_event.c:158
5   Malloc Stats -- (already displayed)
3   devstat -- (already displayed)
3   GEOM orphanage -- (already displayed)
3   bio queue -- (already displayed)
3   bdone lock -- (already displayed)
5   system map -- (already displayed)
2  Giant -- (already displayed)
0 module subsystem sx lock -- last acquired @ kern/kern_module.c:102
0 filelist lock -- last acquired @ kern/kern_descrip.c:1233
3  filedesc structure -- (already displayed)
0 kernel environment -- last acquired @ kern/kern_environment.c:288
0 sysctl lock -- last acquired @ kern/kern_sysctl.c:1273
1  allproc -- last acquired @ kern/kern_fork.c:299
2   Giant -- (already displayed)
0 proctree -- last acquired @ kern/kern_exit.c:573
1  allproc -- (already displayed)

Spin locks:

Locks which were never acquired:
ATAPI CD bioqueue lock
arp_inq
rip
div
udp
ip_inq
ip6_inq
pseudofs_fileno
IPFW dynamic rules
msq
semid
cd9660_ihash
dirhash list
msdosfs dehash
bpf interface lock
if send queue
network driver
netgraph netisr mutex
netgraph idhash mutex
netgraph nodelist mutex
netgraph types mutex
strategy
netisr locbounce pages lock
umtx
rtsock route_cb lock
securelevel mutex lock
jumbo mutex
UUID generator mutex lock
phys_pager list
dev_pager list
dev_pager create
swapdev
swap_pager list
vm map sleep mutex
lockmgr