Severe problems when mounting vfat partitions

Severe problems when mounting vfat partitions

[Olaf Stetzer]

Hello *,

I hope that this is the right place to document my problems:

After some changes in the bios settings and/or rebuilding the kernel
(I don't remember the exact chronology of this..) I get the following
kernel message when I try to mount a vfat partition (either ide/hdd
or a ZIP connected to the SCSI-bus):

Dweezil:~# mount -t msdos /dev/hda5 /mnt
Unable to handle kernel NULL pointer dereference at virtual address 00000004
current->tss.cr3 = 074e4000, %cr3 = 074e4000
*pde = 00000000
Oops: 0000
CPU:    0
EIP:    0010:[<c801ead9>]
EFLAGS: 00010286
eax: 00000000   ebx: c0797df8   ecx: c0797eac   edx: 00000000
esi: 00000305   edi: c0797e60   ebp: c0797ebc   esp: c0797d78
ds: 0018   es: 0018   ss: 0018
Process mount (pid: 416, process nr: 35, stackpage=c0797000)
Stack: c0797e60 c0797ebc c021e6dc c020b0d8 c7fe7400 00000001 c0797dc0 c0180d9b
       c021e6dc c801f4ee 00000000 c0797dec c0797df0 c0797df4 c0797eac c0797e60
       c0797df8 c658f600 00000305 c80763e0 c01f0000 c0113d34 c0797df4 d4afb60c
Call Trace: [<c0180d9b>] [<c801f4ee>] [<c80763e0>] [<c0113d34>] [<c012ab63>] 
[<c0140f88>] [<c0135e32>]
       [<c0135fe0>] [<c0141a69>] [<c80760ca>] [<c8076460>] [<c012c9d4>] 
[<c012ce7e>] [<c8076120>] [<c80763e0>]
       [<c012d31e>] [<c8076120>] [<c80763e0>] [<c010a0ac>]
Code: 66 8b 40 04 66 89 41 04 8a 41 0e 66 c7 41 06 00 00 24 d0 88
Segmentation fault

After this all other attemts to run mount/umount cause this program to
hang completely (I am unable to kill this process!)

I tried to get back to the old bios settings but nothing helped. Really 
strange that this problem occured since a few hours, before everything
worked fine!!!

My system is the following:
Duron 750 on a DFI AK74-SC (VIA KT133)
Kernels I tried: 2.2.17 and 2.2.18
vfat & friends is compiled as modules.
Windows 95 is running fine with the partitions in question so I think
it is not a problem with partition tables (the fact that also the scsi-ZIP
is causing this problem too underlines this!).

If you have any suggestions to solve the problem it would be very kind
to CC them to me (sorry for being a little bit inactive for my part but in
two weeks are my PhD exams and I need this problem to be fixed soon
so I can continue to work on the slides for my PhD presentation...)

Thanks a lot in advance!!!

Olaf 

Re: Severe problems when mounting vfat partitions

[Olaf Stetzer]

Am Samstag, 28. April 2001 20:18 schrieb Andrzej Krzysztofowicz:
> > Dweezil:~# mount -t msdos /dev/hda5 /mnt
> > Unable to handle kernel NULL pointer dereference at virtual address
> > 00000004
>
> One-bit-from-zero address suggests hardware memory problem.
> Did you try to change memory chips ?
>
No, but I solved the problem yesterday at 3:00 in the night! A recompiled
kernel (this time: 2.2.19) did the trick. However, the previous kernels I
compiled with different options were not installed correctly. To be 
precise: I have a small /boot partition where I store the kernels to
boot, but unfortunately make bzlilo was not aware of that fact and so
running lilo always installed the old broken 2.2.17! 

Maybe the error had something to do with other problems mentioned
about a VIA KT133 bug (data corruption...something) but I am quite
happy that I can work again!

Bye,

Olaf