Re: [PATCH net-next v9 3/6] net: add a generation counter for dev->mc changes

[Nicolas Dichtel <nicolas.dichtel@6wind.com>]

Le 30/09/2026 à 13:28, Yuyang Huang a écrit :
> A multi-part RTM_GETMULTICAST dump of dev->mc resumes by position, so
> entries added or removed between two dump rounds can be skipped or
> repeated. The IPv4 and IPv6 dumps report that with NLM_F_DUMP_INTR by
> stamping cb->seq from a per netns generation counter combined with
> dev_base_seq, see inet_base_seq().
> 
> Add the equivalent for the device multicast lists: a per netns counter
> bumped whenever an entry is added to or removed from any dev->mc. The
> list helpers do not know which device a list belongs to, so give
> netdev_hw_addr_list an owner, set for the lists of a device and NULL
> for snapshots and other standalone lists, and bump the counter of
> dev_net(owner) from the count helpers when the list is dev->mc. That
> covers the dev_mc_* helpers, both lists of a sync, the hardware sync
> helpers drivers call from their rx mode callbacks or their own workers
> and the reconciliation after an asynchronous rx mode update. It is
> atomic since the writers only hold the address lock of their own
> device.
> 
> Used by the following patch for the AF_PACKET multicast dump.
> 
> Signed-off-by: Yuyang Huang <sigefriedhyy@gmail.com>

Reviewed-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>