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charset=UTF-8 Content-Transfer-Encoding: 7bit On 11/3/26 22:11, Alexei Starovoitov wrote: > On Tue, Nov 03, 2026 at 12:21 PM Harry Yoo wrote: >> While this is technically true, this relies too much on the current >> implementation details and makes the code hard to follow. > > Fair enough. I don't insist. > >> Patch 2 is an independent bugfix as-is already. We should really stop >> open-coding slab_free_hook(). That ended up missing init_on_free handing. > > Right. No objection to patch 2. > With patches 2 and 3 the !allow_spin side of memcg_alloc_abort_single() > is an open coded kfree_nolock(): > > kfree_nolock() memcg_alloc_abort_single(!allow_spin) > -------------------------------- ------------------------------------- > memcg_slab_free_hook() - > alloc_tagging_slab_free_hook() alloc_tagging_slab_free_hook() > slab_free_hook(!allow_spin) slab_free_hook(!allow_spin) > free_to_pcs() - > defer_free() defer_free() > > I don't insist on kfree_nolock() there, > but can we try free_to_pcs() before defer_free() ? > Like: > > if (likely(allow_spin)) > __slab_free(s, slab, object, object, 1, _RET_IP_); > else if (!can_free_to_pcs(slab) || !free_to_pcs(s, object, false)) > defer_free(s, object); Why not try free_to_pcs with allow_spin as well then, and improve memcg_alloc_abort_single() for both contexts?