Hi,

While playing with SVN head ScummVM emulator, i'm experiencing kernel
panics. This is on my i386 laptop running -current 4.99.1, and this
host is currently missing a serial port ... no remote console.

The problem is that blindly typing `sync', from X, does not do
anything. I have to issue it twice to get the expected kernel core
file. The first call seems to produce another panic (panic: lockmgr:
locking against myself) which hide the real problem ...

Any hint to get around this problem ?

Here follow the backtrace i currently have :

(gdb) bt
#0  0x0f03b000 in ?? ()
#1  0xc03fac79 in cpu_reboot (howto=256, bootstr=0x0)
    at /local/src/NetBSD/src/sys/arch/i386/i386/machdep.c:869
#2  0xc01b0bf4 in db_sync_cmd (addr=-1066395616, have_addr=0, 
    count=-1071960727, modif=0xcb180178 "#\030pĀc")
    at /local/src/NetBSD/src/sys/ddb/db_command.c:811
#3  0xc01b1178 in db_command (last_cmdp=0xc06bf83c, cmd_table=0xc0582780)
    at /local/src/NetBSD/src/sys/ddb/db_command.c:508
#4  0xc01b145f in db_command_loop ()
    at /local/src/NetBSD/src/sys/ddb/db_command.c:296
#5  0xc01b3ede in db_trap (type=1, code=0)
    at /local/src/NetBSD/src/sys/ddb/db_trap.c:101
#6  0xc03f76cd in kdb_trap (type=1, code=0, regs=0xcb180390)
    at /local/src/NetBSD/src/sys/arch/i386/i386/db_interface.c:226
#7  0xc040549b in trap (frame=0xcb180390)
    at /local/src/NetBSD/src/sys/arch/i386/i386/trap.c:313
#8  0xc0102ecf in calltrap ()
#9  0xc0383a75 in panic (fmt=0xc06950bc "lockmgr: locking against myself")
    at /local/src/NetBSD/src/sys/kern/subr_prf.c:243
#10 0xc03638fa in lockmgr (lkp=0xcb7b0518, flags=65554, interlkp=0xcb7b04a8)
    at /local/src/NetBSD/src/sys/kern/kern_lock.c:759
#11 0xc03b237f in genfs_lock (v=0xcb180474)
    at /local/src/NetBSD/src/sys/miscfs/genfs/genfs_vnops.c:301
#12 0xc03b0f43 in VOP_LOCK (vp=0xcb7b04a8, flags=65554)
    at /local/src/NetBSD/src/sys/kern/vnode_if.c:1228
#13 0xc03ae6d8 in vn_lock (vp=0xcb7b04a8, flags=65554)
    at /local/src/NetBSD/src/sys/kern/vfs_vnops.c:727
#14 0xc03a7690 in vget (vp=0xcb7b04a8, flags=65554)
    at /local/src/NetBSD/src/sys/kern/vfs_subr.c:1206
#15 0xc02ff37a in ffs_sync (mp=0xc0de6000, waitfor=2, cred=0xca760f3c, 
    l=0xca76d578) at /local/src/NetBSD/src/sys/ufs/ffs/ffs_vfsops.c:1328
#16 0xc03acd98 in sys_sync (l=0xca76d578, v=0x0, retval=0x0)
    at /local/src/NetBSD/src/sys/kern/vfs_syscalls.c:693
#17 0xc03a79ab in vfs_shutdown ()
    at /local/src/NetBSD/src/sys/kern/vfs_subr.c:2217
#18 0xc03fad57 in cpu_reboot (howto=256, bootstr=0x0)
    at /local/src/NetBSD/src/sys/arch/i386/i386/machdep.c:855
#19 0xc01b0bf4 in db_sync_cmd (addr=-1066395616, have_addr=0, 
    count=-1071960727, modif=0xcb1805b4 "#\030pĀc")
    at /local/src/NetBSD/src/sys/ddb/db_command.c:811
#20 0xc01b1178 in db_command (last_cmdp=0xc06bf83c, cmd_table=0xc0582780)
    at /local/src/NetBSD/src/sys/ddb/db_command.c:508
#21 0xc01b145f in db_command_loop ()
    at /local/src/NetBSD/src/sys/ddb/db_command.c:296
#22 0xc01b3ede in db_trap (type=6, code=0)
    at /local/src/NetBSD/src/sys/ddb/db_trap.c:101
#23 0xc03f76cd in kdb_trap (type=6, code=0, regs=0xcb1807cc)
    at /local/src/NetBSD/src/sys/arch/i386/i386/db_interface.c:226
#24 0xc040549b in trap (frame=0xcb1807cc)
    at /local/src/NetBSD/src/sys/arch/i386/i386/trap.c:313
#25 0xc0102ecf in calltrap ()
#26 0xc02ee301 in ffs_truncate (ovp=0xcb7b04a8, length=4088, ioflag=0, 
    cred=0xca760f3c, l=0xca76d578)
    at /local/src/NetBSD/src/sys/ufs/ffs/ffs_inode.c:281
#27 0xc0302049 in ffs_write (v=0xcb180b08)
    at /local/src/NetBSD/src/sys/ufs/ufs/ufs_readwrite.c:493
#28 0xc03b0b4b in VOP_WRITE (vp=0xcb7b04a8, uio=0xcb180ba0, ioflag=16, 
    cred=0xca760f3c) at /local/src/NetBSD/src/sys/kern/vnode_if.c:462
#29 0xc03aea0e in vn_write (fp=0xca77ab7c, offset=0xca77aba8, uio=0xcb180ba0, 
    cred=0xca760f3c, flags=1) at /local/src/NetBSD/src/sys/kern/vfs_vnops.c:512
#30 0xc038694b in dofilewrite (l=0xca76d578, fd=2, fp=0xca77ab7c, 
    buf=0x81e1320, nbyte=58, offset=0xca77aba8, flags=1, retval=0xcb180c68)
    at /local/src/NetBSD/src/sys/kern/sys_generic.c:380
#31 0xc0386a82 in sys_write (l=0xca76d578, v=0xcb180c48, retval=0xcb180c68)
    at /local/src/NetBSD/src/sys/kern/sys_generic.c:331
#32 0xc0404cd1 in syscall_plain (frame=0xcb180c88)
    at /local/src/NetBSD/src/sys/arch/i386/i386/syscall.c:144

Thanks in advance,
Regards.

-- 
Nicolas Joly

Biological Software and Databanks.
Institut Pasteur, Paris.