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List-Unsubscribe: On Thu, Jan 08, 2026 at 01:52:09PM +0800, Hao Li wrote: > On Mon, Jan 05, 2026 at 05:02:30PM +0900, Harry Yoo wrote: > > When a cache has high s->align value and s->object_size is not aligned > > to it, each object ends up with some unused space because of alignment. > > If this wasted space is big enough, we can use it to store the > > slabobj_ext metadata instead of wasting it. > > Hi, Harry, Hi Hao, > When we save obj_ext in s->size space, it seems that slab_ksize() might > be missing the corresponding handling. Oops. > It still returns s->size, which could cause callers of slab_ksize() > to see unexpected data (i.e. obj_ext), or even overwrite the obj_ext data. Yes indeed. Great point, thanks! I'll fix it by checking if the slab has obj_exts within the object layout and returning s->object_size if so. -- Cheers, Harry / Hyeonggon