today's 8.1/i386: panic: bad pte

[Alan Cox]

On Mon, Jul 19, 2010 at 11:40 PM, Mikhail T.
<mi+thun at aldan.algebra.com<mi%2Bthun at aldan.algebra.com>
> wrote:

> Some part of KDE4's kdm crashed at start-up and seems to have taken the
> entire machine with it:
>
>   kgdb /boot/kernel/kernel /var/crash/vmcore.22
>   GNU gdb 6.1.1 [FreeBSD]
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>   This GDB was configured as "i386-marcel-freebsd"...
>
>   Unread portion of the kernel message buffer:
>   <6>pid 18398 (drkonqi), uid 0: exited on signal 11 (core dumped)
>   TPTE at 0xbfca9488  IS ZERO @ VA 2a522000
>   panic: bad pte
>   Uptime: 2h28m24s
>   Physical memory: 1263 MB
>   Dumping 195 MB: 180 164 148 132 116 100 84 68 52 36 20 4
>
>   Reading symbols from /boot/kernel/splash_pcx.ko...Reading symbols
>   from /boot/kernel/splash_pcx.ko.symbols...done.
>   done.
>   Loaded symbols for /boot/kernel/splash_pcx.ko
>   Reading symbols from /boot/kernel/vesa.ko...Reading symbols from
>   /boot/kernel/vesa.ko.symbols...done.
>   done.
>   Loaded symbols for /boot/kernel/vesa.ko
>   Reading symbols from /boot/modules/nvidia.ko...done.
>   Loaded symbols for /boot/modules/nvidia.ko
>   Reading symbols from /boot/kernel/linux.ko...Reading symbols from
>   /boot/kernel/linux.ko.symbols...done.
>   done.
>   Loaded symbols for /boot/kernel/linux.ko
>   Reading symbols from /boot/kernel/acpi.ko...Reading symbols from
>   /boot/kernel/acpi.ko.symbols...done.
>   done.
>   Loaded symbols for /boot/kernel/acpi.ko
>   Reading symbols from /boot/kernel/linprocfs.ko...Reading symbols
>   from /boot/kernel/linprocfs.ko.symbols...done.
>   done.
>   Loaded symbols for /boot/kernel/linprocfs.ko
>   #0  doadump () at pcpu.h:231
>   231             __asm __volatile("movl %%fs:0,%0" : "=r" (td));
>   (kgdb) bt full
>   #0  doadump () at pcpu.h:231
>   No locals.
>   #1  0xc05d10a4 in boot (howto=260) at
>   /usr/src/sys/kern/kern_shutdown.c:416
>            _giantcnt = Variable "_giantcnt" is not available.
>   (kgdb) where
>   #0  doadump () at pcpu.h:231
>   #1  0xc05d10a4 in boot (howto=260) at
>   /usr/src/sys/kern/kern_shutdown.c:416
>   #2  0xc05d12b1 in panic (fmt=Variable "fmt" is not available.
>   ) at /usr/src/sys/kern/kern_shutdown.c:590
>   #3  0xc07f0406 in pmap_remove_pages (pmap=0xc85bbc78) at
>   /usr/src/sys/i386/i386/pmap.c:4198
>   #4  0xc079516b in vmspace_exit (td=0xc51f3a00) at
>   /usr/src/sys/vm/vm_map.c:409
>   #5  0xc05a7253 in exit1 (td=0xc51f3a00, rv=139) at
>   /usr/src/sys/kern/kern_exit.c:303
>   #6  0xc05d3296 in sigexit (td=0xc51f3a00, sig=139) at
>   /usr/src/sys/kern/kern_sig.c:2872
>   #7  0xc05d47a8 in postsig (sig=11) at /usr/src/sys/kern/kern_sig.c:2759
>   #8  0xc06082f8 in ast (framep=0xe5fafd38) at
>   /usr/src/sys/kern/subr_trap.c:234
>   #9  0xc07e2c44 in doreti_ast () at
>   /usr/src/sys/i386/i386/exception.s:368
>
> Does this look familiar to anyone? Thanks!
>
>
Historically, this panic has indicated flakey memory.  This panic occurs
because a memory location within a page table has unexpectedly changed to
zero.

Alan