netdev - Re: [PATCH net-next v2] net: core: decouple ifalias get/set from rtnl lock

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Date:   Mon, 2 Oct 2017 17:09:36 +0200
From:   Florian Westphal <fw@...len.de>
To:     Eric Dumazet <eric.dumazet@...il.com>
Cc:     Florian Westphal <fw@...len.de>, netdev@...r.kernel.org
Subject: Re: [PATCH net-next v2] net: core: decouple ifalias get/set from
 rtnl lock

Eric Dumazet <eric.dumazet@...il.com> wrote:
> Just use RCU : A writer is supposed to work on a private copy, and
> _then_ publish the new pointer, so that a reader can not see mangled
> string.
> 
> We either copy the 'old' name or the 'new' one.
> 
> A seqcount is not needed, and wont prevent you from reading the value
> right before a change anyway.

Would you rather use kfree_rcu or unconditional synchronize_net()
before releasing old memory?