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> + enum global_enabled_mode m; > + bool changed = false; > + > + for (m = 0; m < ARRAY_SIZE(thp_flags); m++) { > + if (m == mode) > + changed |= !__test_and_set_bit(thp_flags[m], > + &transparent_hugepage_flags); > + else > + changed |= __test_and_clear_bit(thp_flags[m], > + &transparent_hugepage_flags); I am not a mm expert and typically do not follow the mm list. Is there an issue with the usage of non-atomic variants here? The commit message says this uses the same pattern as set_anon_enabled_mode(). However, set_anon_enabled_mode() has a spinlock=>huge_anon_orders_lock protecting the access. But, transparent_hugepage_flags seems to be unprotected in that regard. IIUC, David's suggestion to use the lockless version was also based on the use of a lock in that context. https://lore.kernel.org/all/4f2abf42-983f-4cc2-92f5-c81827e7b7e2@kernel.org/ Note: We ran into this issue while experimenting with an AI review agent internally. The patch was selected at random from the mailing list. I analyzed the issue independently and came to the same conclusion. I apologize if this is a false alarm. > + } > + > + return changed; > +} > +