Hey everyone, I've got a question. I've got an eBPF map that's a BPF_MAP_TYPE_HASH_OF_MAPS where user space updates elements in the map, user space will create a new inner map to do map-in-map swapping in order to update the outer map's values. My XDP program will then read the inner maps by using BPF_MAP_LOOKUP_ELEM on the outer map. Does this create a potential race condition between BPF_MAP_LOOKUP_ELEM and BPF_MAP_UPDATE_ELEM when one thread is trying to lookup an existing element while another thread is trying to update the same existing element? I'm expecting to see either the old value or the new value, however I'm occasionally seeing the element does not exist when looking up the element from the eBPF program. Is this expected? Thanks, Cody Haas
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