Re: BUG: unable to handle kernel paging request xfs_is_delayed_page

[Christoph Hellwig <hch@xxxxxxxxxxxxx>]

On Thu, Jul 21, 2011 at 11:55:04PM +0300, T?r?k Edwin wrote:
> Not sure what the BUG means: did XFS ran out of memory when trying to write 
> the 4GB coredump, as it wanted to allocate an extra 4G temporarely to hold it?
> 

It means we dereferenced an invalid pointer in xfs_is_delayed_page,
which is called from the writeback code, which is pretty odd.  We
haven't really touched that particular piece of code for a long time,
and it really doesn't derefence many pointers, basically just
page->mapping, page->private and the flags and b_this_page fields
in the buffer head.