From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Abeni <pabeni@redhat.com>
Subject: Re: [PATCH net] ipv6: kill sk_dst_lock
Date: Mon, 30 Nov 2015 19:13:08 +0100
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Cc: Dmitry Vyukov <dvyukov@google.com>,
	"David S. Miller" <davem@davemloft.net>,
	Vlad Yasevich <vyasevich@gmail.com>,
	Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
	netdev <netdev@vger.kernel.org>
To: Eric Dumazet <eric.dumazet@gmail.com>
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On Mon, 2015-11-30 at 08:35 -0800, Eric Dumazet wrote:
> ip6_sk_dst_lookup_flow() uses sk_dst_check() anyway, so the simplest
> way to fix the mess is to remove sk_dst_lock completely, as we did for
> IPv4.

Probably I'm missing something here, but why we don't need to sync the
update of sk_dst_cache and of dst_cookie (i.e. put them under the same
lock)?

Can't we end up with inconsistent values after concurrent udp
sendmsg() ? 

Cheers,

Paolo