On Wed, Nov 06, 2013 at 08:54:17PM +0100, Andreas Herrmann wrote: > On Wed, Nov 06, 2013 at 02:16:33PM -0500, Christoph Lameter wrote: > > On Wed, 6 Nov 2013, Andreas Herrmann wrote: > > > > > When I've used slub_debug kernel option (e.g. > > > "slub_debug=,skbuff_fclone_cache" or similar) on a debug session I've > > > seen a panic like: > > > > Hmmm.. That looks like its due to some slabs not having names > > during early boot. kmem_cache_flags is called with NULL as a parameter. > > That's because the slub_debug parameter is not evaluated before > kmem_cache_flags is called. > > Older kernels didn't show this problem. I think the sequence of those > calls has changed. Not sure what patch set has made that change. Please ignore this comment. I revisisted the code and of course you are right. Hmm, now wondering why my patch covered the panic. > > Are you sure that this fixes the issue? Looks like the > > kmem_cache_flag function should fail regardless of how early you set it. > > > > AFAICT the right fix would be: > > That would avoid the panic but I guess it won't enable slub debugging. Ok, the latter is bogus. Of course debugging is switched on. > However I'll test this. Your patch fixed it. Andreas -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>