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It is forbidden to hold a spin lock around copyout, and t_lock is a spin lock. We need t_lock in order to iterate over the list of entries. However, during copyout itself, we only need to ensure that the object we're copying out isn't freed by npf_table_remove or npf_table_gc. Fortunately, the only caller of npf_table_list, npf_table_remove, and npf_table_gc is npfctl_table, and it serializes all of them by the npf config lock. So we can safely drop t_lock across copyout. https://gnats.NetBSD.org/57136 https://gnats.NetBSD.org/57181
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It is forbidden to hold a spin lock around copyout, and t_lock is a spin lock.
We need t_lock in order to iterate over the list of entries. However, during copyout itself, we only need to ensure that the object we're copying out isn't freed by npf_table_remove or npf_table_gc.
Fortunately, the only caller of npf_table_list, npf_table_remove, and npf_table_gc is npfctl_table, and it serializes all of them by the npf config lock. So we can safely drop t_lock across copyout.
https://gnats.NetBSD.org/57136
https://gnats.NetBSD.org/57181