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> + timer_delete_sync(&pmctx->ip6_own_query_timer); > #endif > timer_delete_sync(&pmctx->ip4_mc_router_timer); > + timer_delete_sync(&pmctx->ip4_own_query_timer); > > spin_lock_bh(&br->multicast_lock); > del |= br_ip6_multicast_rport_del(pmctx); Thanks for the report and the fix. It looks correct, but it's unclear to me which commit to blame. AFAICT, the trace tells us that the timer is pending (not executing) when the object that contains it is RCU freed. However, it shouldn't be possible for the timer to be pending at this stage since it is deactivated when the port multicast context is disabled and it is only reactivated if the context is not disabled. So, I see two options: 1. We did not disable port multicast context. 2. We did disable the port multicast context, but the timer somehow got reactivated. I will look into it...