From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH v2 net] inet: frags: better deal with smp races
Date: Thu, 08 Nov 2018 18:41:17 -0800 (PST)
Message-ID: <20181108.184117.1189358377262405362.davem@davemloft.net>
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From: Eric Dumazet <edumazet@google.com>
Date: Thu,  8 Nov 2018 17:34:27 -0800

> Multiple cpus might attempt to insert a new fragment in rhashtable,
> if for example RPS is buggy, as reported by ¹è¼®Áø in
> https://patchwork.ozlabs.org/patch/994601/
> 
> We use rhashtable_lookup_get_insert_key() instead of
> rhashtable_insert_fast() to let cpus losing the race
> free their own inet_frag_queue and use the one that
> was inserted by another cpu.
> 
> Fixes: 648700f76b03 ("inet: frags: use rhashtables for reassembly units")
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> Reported-by: ¹è¼®Áø <soukjin.bae@samsung.com>

Applied and queued up for -stable, thanks.