Re: [PATCH] slub/slab: fix kmemleak didn't work on some case

[Christoph Lameter]

On Mon, 8 Jun 2015, Liu, XinwuX wrote:

> when kernel uses kmalloc to allocate memory, slub/slab will find
> a suitable kmem_cache. Ususally the cache's object size is often
> greater than requested size. There is unused space which contains
> dirty data. These dirty data might have pointers pointing to a block

dirty? In what sense?

> of leaked memory. Kernel wouldn't consider this memory as leaked when
> scanning kmemleak object.

This has never been considered leaked memory before to my knowledge and
the data is already initialized.

F.e. The zeroing function in linux/mm/slub.c::slab_alloc_node() zeros the
complete object and not only the number of bytes specified in the kmalloc
call. Same thing is true for SLAB.

I am a bit confused as to what issue this patch would address.

Also please send clean patches without special characters. Ensure proper
tabbing etc.

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