Bug #755

disklabel -r -W md0s0 enters into debugger

Added by kmb810 over 6 years ago. Updated over 6 years ago.

Status:ClosedStart date:
Priority:NormalDue date:
Assignee:-% Done:


Target version:-


Hello All,

I synced with the lattest head an hour ago and ran into the following problem:
Trying to configure memory disk and disklabel -r -W md0s0 enters into debugger.

mdstrategy_malloc+0x11a : page fault while in kernel mode.

So I took a crash dump and nailed down the problem to the following point.

to mdstrategy_malloc via ap->bio and mdstrategy_malloc blows up at

This problem is reproducible.

Going to sleep now will try to fix this after work tomorrow if it's
not already been fixed by Matt then.

Backtrace is as follows:

#0 dumpsys () at thread.h:83
#1 0xc013e8ad in db_fncall (dummy1=1936, dummy2=0, dummy3=-560314676,
dummy4=0xde9a46c8 "�\a")
at /usr/src/sys/ddb/db_command.c:541
#2 0xc013e667 in db_command (last_cmdp=0xc0384770, cmd_table=0x0,
aux_cmd_tablep_end=0xc0352218) at /usr/src/sys/ddb/db_command.c:343
#3 0xc013e747 in db_command_loop () at /usr/src/sys/ddb/db_command.c:469
#4 0xc0141300 in db_trap (type=12, code=0) at /usr/src/sys/ddb/db_trap.c:71
#5 0xc02e59e3 in kdb_trap (type=12, code=0, regs=0xde9a485c) at
#6 0xc02fe72e in trap_fatal (frame=0xde9a485c, eva=0) at
#7 0xc02fe3a5 in trap_pfault (frame=0xde9a485c, usermode=0, eva=0) at
#8 0xc02fdf64 in trap (frame=0xde9a485c) at
#9 0xc02e6aa6 in calltrap () at /usr/src/sys/platform/pc32/i386/exception.s:783
#10 0xc0181196 in mdstrategy_malloc (ap=0xff800000) at buf2.h:163
#11 0xc018105d in mdstrategy (ap=0xde9a4940) at
#12 0xc01a5712 in dev_dstrategy (dev=0xd9e93ef8, bio=0x0) at
#13 0xc01d58b2 in diskstrategy (ap=0xff800000) at
#14 0xc01a5712 in dev_dstrategy (dev=0xd9e93f88, bio=0x0) at
#15 0xc031252d in mbrinit (dev=0xd9e9c448, info=0xd33779fc, sspp=0xd33779f8)
at /usr/src/sys/kern/subr_diskmbr.c:129
#16 0xc01d8822 in dsopen (dev=0xd9e9c448, mode=8192, flags=1,
sspp=0xd33779f8, info=0xd33779fc)
at /usr/src/sys/kern/subr_diskslice.c:808
#17 0xc01d56ef in diskopen (ap=0xde9a4ab8) at /usr/src/sys/kern/subr_disk.c:334
#18 0xc01a54fd in dev_dopen (dev=0xc40b2c00, oflags=-8388608,
devtype=-8388608, cred=0xff800000)
at /usr/src/sys/kern/kern_device.c:112
#19 0xc021d422 in spec_open (ap=0xde9a4b28) at
#20 0xc021d232 in spec_vnoperate (ap=0xc40b2c00) at
#21 0xc0290276 in ufs_vnoperatespec (ap=0xc40b2c00) at
#22 0xc0218468 in vop_open (ops=0xc40b2c00, vp=0xff800000,
mode=-8388608, cred=0xff800000, fp=0xff800000)
at /usr/src/sys/kern/vfs_vopops.c:242
#23 0xc0217398 in vn_open (nd=0xde9a4c70, fp=0xd3389a50, fmode=3,
cmode=2341) at /usr/src/sys/kern/vfs_vnops.c:298
#24 0xc021376e in kern_open (nd=0xde9a4c70, oflags=0, mode=134679349,
at /usr/src/sys/kern/vfs_syscalls.c:1499
#25 0xc02139d6 in sys_open (uap=0xde9a4cf8) at
#26 0xc02feb51 in syscall2 (frame=0xde9a4d40) at
#27 0xc02e6b45 in Xint0x80_syscall () at


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