Re: Kernel bug: Bad page state: related to generic symlink code and mmap

[Al Viro <viro@parcelfarce.linux.theplanet.co.uk>]

On Fri, Aug 19, 2005 at 12:14:48PM +0100, Anton Altaparmakov wrote:
> Hi,
> 
> There is a bug somewhere in 2.6.11.4 and I can't figure out where it is.
> I assume it is present in older and newer kernels, too as the related
> code hasn't changed much AFAICS and googling for "Bad page state"
> returns rather a lot of hits relating to both older (up to 2.5.70!) and
> newer kernels...
> 
> Note: PLEASE do not stop reading because you read ncpfs below as I am
> pretty sure it is not ncpfs related!  And looking at google a lot of
> people have reported such similar problems since 2.5.70 or so and they
> were all told to go away as they have bad ram.  That is impossible
> because this happens on well over 600 workstations and several servers
> 100% reproducible.  Many different types of hardware, different makes,
> difference age, all running smp kernels even if single cpu.  You can't
> tell me they all have bad ram.  Windows works fine and Linux works fine
> except for that one specific problem which is 100% reproducible...
> 
> The bug only appears, but it appears 100% reproducibly when a cross
> volume symlink on ncpfs is accessed using nautilus under gnome.  I.e.
> double click on a cross volume symlink on ncpfs in nautilus and the
> machine locks up solid.

Ugh...  Could you at least tell what does nautilus attempt to do at that
point?  Something that wouldn't show up with simple ls -l <symlink> or
cat <symlink> >/dev/null, judging by the above, but what?