[Linux-cachefs] Hitting a kernel bug with active cache

[Hans Meine]

Hi,

for some days I've been getting syslog messages which I now tracked down to 
this assertion ("kernel BUG at fs/nfs/fscache.c:385!"):

/*
 * Release the caching state associated with a page if undergoing complete
 * page invalidation.
 */
void __nfs_fscache_invalidate_page(struct page *page, struct inode *inode)
{
	struct nfs_inode *nfsi = NFS_I(inode);
	struct fscache_cookie *cookie = nfsi->fscache;

	BUG_ON(!cookie); <========== failing line 385

I must admit that I spent too much time recently on sysadmin things, so I am 
not too eager to debug this, but I thought I should let you know, just in case 
that this is something which really should not have happened.

I don't know what triggered it; I had been using fscache (on a 2.6.34 kernel) 
successfully for (maybe exactly) two weeks now, and suddenly I got these 
problems.  (I stopped caching for now, in order to get other things done.)  
Interestingly, it were always the same programs/actions which made problems, 
possibly because they were accessing some specific files..

I also tried updating my kernel to 2.6.35, but that did not change anything.
(You might remember from my first posting that I am using NFS4 with Kerberos 
etc.)

Have a nice day,
  Hans