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X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, Jun 13, 2025 at 09:04:34AM -0700, Christoph Lameter (Ampere) wrote: > On Fri, 13 Jun 2025, Harry Yoo wrote: > > > Allocate slabobj_exts array from this unused space instead of using > > kcalloc(), when it is large enough. > > How does slab debug work in this case? The object layout gets a bit > complicated with other metadata there as well. Oh, the 'leftover' space I mentioned the cover letter refers to the wasted space after the last object in a slab, not unused bytes within objects. There is no per-object metadata stored there and SLUB simply poisons the area. I taught slab_pad_check() to skip checking the slabobj_exts array. -- Cheers, Harry / Hyeonggon