From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH] net: Fix IP_MULTICAST_IF
Date: Tue, 20 Oct 2009 06:23:54 +0200
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To: David Miller <davem@davemloft.net>
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David Miller a =E9crit :
> From: Eric Dumazet <eric.dumazet@gmail.com>
> Date: Tue, 20 Oct 2009 06:07:48 +0200
>=20
>> Final target might be fine, but an element in the chain, before targ=
et
>> could be deleted while reader scans hash chain.
>  ...
>> So it should visit a nice memory location ?
>=20
> It should hit a NULL eventually and deterministically even if an
> unlink happens at the same time..... unless the object gets free'd
> meanwhile, hmmm...
>=20
> This code is definitely intentional, I remember when I added it to
> the tree, Alexey wrote it :-)

I wonder if the whole thing could use RCU somehow, since some workloads=
 hit
this dev_base_lock rwlock pretty hard...