From mboxrd@z Thu Jan  1 00:00:00 1970
From: Daniel Borkmann <daniel@iogearbox.net>
Subject: Re: [PATCH bpf] xsk: do not call synchronize_net() under RCU read
 lock
Date: Thu, 11 Oct 2018 10:22:20 +0200
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On 10/08/2018 07:40 PM, Björn Töpel wrote:
> From: Björn Töpel <bjorn.topel@intel.com>
> 
> The XSKMAP update and delete functions called synchronize_net(), which
> can sleep. It is not allowed to sleep during an RCU read section.
> 
> Instead we need to make sure that the sock sk_destruct (xsk_destruct)
> function is asynchronously called after an RCU grace period. Setting
> the SOCK_RCU_FREE flag for XDP sockets takes care of this.
> 
> Fixes: fbfc504a24f5 ("bpf: introduce new bpf AF_XDP map type BPF_MAP_TYPE_XSKMAP")
> Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
> Signed-off-by: Björn Töpel <bjorn.topel@intel.com>

Applied to bpf, thanks everyone!