On Wed, 8 Nov 2017, Miles Chen wrote: > > Ok then the aliasing failed for some reason. The creation of the unique id > > and the alias detection needs to be in sync otherwise duplicate filenames > > are created. What is the difference there? > > The aliasing failed because find_mergeable() returns if (flags & > SLAB_NEVER_MERGE) is true. So we do not go to search for alias caches. > > __kmem_cache_alias() > find_mergeable() > kmem_cache_flags() --> setup flag by the slub_debug > if (flags & SLAB_NEVER_MERGE) return NULL; > ... > search alias logic... > > > The flags maybe changed if disable_higher_order_debug=1. So the > unmergeable cache becomes mergeable later. Ok so make sure taht the aliasing logic also clears those flags before checking for SLAB_NEVER_MERGE. > > The clearing of the DEBUG_METADATA_FLAGS looks ok to me. kmem_cache_alias > > should do the same right? > > > Yes, I think clearing DEBUG_METADATA flags in kmem_cache_alias is > another solution for this issue. > > We will need to do calculate_sizes() by using original flags and compare > the order of s->size and s->object_size when > disable_higher_order_debug=1. Hmmm... Or move the aliasing check to a point where we know the size of the slab objects? -- 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>
