trying to mount a write prptected zip disk panics the machine (unless the -r flag is used)

Torfinn Ingolfsen torfinn.ingolfsen at
Mon Aug 18 17:44:41 UTC 2008

On Mon, 18 Aug 2008 10:33:05 -0400
John Baldwin <jhb at> wrote:

> Can you get the stack trace?

Like this?
root at music1# kgdb kernel.debug /var/crash/vmcore.0
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Unread portion of the kernel message buffer:

Fatal trap 12: page fault while in kernel mode
cpuid = 0; apic id = 00
fault virtual address   = 0x0
fault code              = supervisor read, page not present
instruction pointer     = 0x20:0xc0737b19
stack pointer           = 0x28:0xceb9cbcc
frame pointer           = 0x28:0xceb9cbf8
code segment            = base 0x0, limit 0xfffff, type 0x1b
                        = DPL 0, pres 1, def32 1, gran 1
processor eflags        = interrupt enabled, resume, IOPL = 0
current process         = 42 (syncer)
trap number             = 12
panic: page fault
cpuid = 0
Uptime: 24m34s
Physical memory: 307 MB
Dumping 58 MB: 43 27 11

Reading symbols from /boot/kernel/acpi.ko...Reading symbols
from /boot/kernel/acpi.ko.symbols...done. done.
Loaded symbols for /boot/kernel/acpi.ko
#0  doadump () at pcpu.h:195
195             __asm __volatile("movl %%fs:0,%0" : "=r" (td));
(kgdb) backtrace
#0  doadump () at pcpu.h:195
#1  0xc078eed7 in boot (howto=260)
#at /usr/src/sys/kern/kern_shutdown.c:418 2  0xc078f199 in panic
#(fmt=Variable "fmt" is not available.
) at /usr/src/sys/kern/kern_shutdown.c:572
#3  0xc0a9efbc in trap_fatal (frame=0xceb9cb8c, eva=0)
#at /usr/src/sys/i386/i386/trap.c:899 4  0xc0a9f240 in trap_pfault
#(frame=0xceb9cb8c, usermode=0, eva=0)
#at /usr/src/sys/i386/i386/trap.c:812 5  0xc0a9fbec in trap
#(frame=0xceb9cb8c) at /usr/src/sys/i386/i386/trap.c:490 6  0xc0a859ab
#in calltrap () at /usr/src/sys/i386/i386/exception.s:139 7  0xc0737b19
#in g_io_request (bp=0xc299ba50, cp=0xc29b2e00)
#at /usr/src/sys/geom/geom_io.c:364 8  0xc073c116 in g_vfs_strategy
#(bo=0xc29881d4, bp=0xc88efc24) at /usr/src/sys/geom/geom_vfs.c:107 9
#0xc07f97b0 in bufwrite (bp=0xc88efc24) at buf.h:429 10 0xc07f2618 in
#bawrite (bp=0xc88efc24) at buf.h:417 11 0xc07fddaa in vop_stdfsync
#(ap=0xceb9ccd4) at /usr/src/sys/kern/vfs_default.c:479 12 0xc071cbbe
#in devfs_fsync (ap=0xceb9ccd4)
#at /usr/src/sys/fs/devfs/devfs_vnops.c:395 13 0xc0ab3ce2 in
#VOP_FSYNC_APV (vop=0xc0bcf040, a=0xceb9ccd4) at vnode_if.c:1007 14
#0xc080dff8 in sched_sync () at vnode_if.h:538 15 0xc076bc59 in
#fork_exit (callout=0xc080d8f0 <sched_sync>, arg=0x0, frame=0xceb9cd38)
    at /usr/src/sys/kern/kern_fork.c:781
#16 0xc0a85a20 in fork_trampoline ()
#at /usr/src/sys/i386/i386/exception.s:205

Let me know if it was wrong, or if you need something else.
Torfinn Ingolfsen

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