kern/122961: write operation on msdosfs file system causes panic

[Bruce Evans]

On Fri, 2 May 2008, Dominic Fandrey wrote:

> Bruce Evans wrote:
>> On Wed, 23 Apr 2008, Dominic Fandrey wrote:
>> 
>>> Bruce Evans wrote:
>>>> The broken nocluster* can be worked around by upgrading to a version of
>>>> mount_msdsosfs(8) that hasn't been broken by using nmount(2).
>>>> mount_msdsosfs(8) from RELENG_5 should work.
>>> 
>>> I feel reluctant about downgrading to 5.x mount_msdosfs,
>> 
>> But it would be an upgrage :-).  Anyway, running mount_msdosfs on one
>> disposable file system that might panic should be safe.
>> 
>>> however I can confirm that cp with large files does _not_ cause a panic. 
>>> As far as I understand this confirms your theory.
>> 
>> Not quite.  I would have expected the problem to affect read() and write()
>> too unless the file system is mounted with -nocluster*.
>
> This can be closed.
>
> Your suggestions have been very helpful. It turned out that fusefs-ntfs is 
> causing the panic, when I copy files from it.

Now we have a better argument for not axing non-port ntfs :-).  I think
it sort of works read-only.  Too bad we're no closer to understand the
msdosfs problem.

Bruce