Re: [PATCH v2] net/mlx4_en: protect ring->xdp_prog with rcu_read_lock

From: Brenden Blanco Date: Sat, 3 Sep 2016 21:29:58 -0700 > Depending on the preempt mode, the bpf_prog stored in xdp_prog may be > freed despite the use of call_rcu inside bpf_prog_put. The situation is > possible when running in PREEMPT_RCU=y mode, for instance, since

[PATCH v2] net/mlx4_en: protect ring->xdp_prog with rcu_read_lock

Depending on the preempt mode, the bpf_prog stored in xdp_prog may be freed despite the use of call_rcu inside bpf_prog_put. The situation is possible when running in PREEMPT_RCU=y mode, for instance, since the rcu callback for destroying the bpf prog can run even during the bh handling in the