Re: [PATCH net] net: bonding: annotate lockless writes with WRITE_ONCE()

[Paolo Abeni <pabeni@redhat.com>]

On 8/31/26 10:10 AM, Eric Dumazet wrote:
> Several fields in bonding are read locklessly using READ_ONCE()
> (or ACCESS_ONCE() previously) but have corresponding writes that
> do not use WRITE_ONCE().
> 
> Add WRITE_ONCE() annotations to:
> - bond->send_peer_notif decrements in bond_peer_notify_may_events()
>   and reset in bond_close().
> - bond->slave_cnt increments and decrements in bond_enslave() and
>   __bond_release_one().
> - bond->recv_probe updates in bond_open(), bond_option_arp_interval_set()
>   and rlb_initialize().
> - slaves->count decrement in bond_skip_slave().
> 
> Fixes: 4d97480b1806 ("bonding: use local function pointer of bond->recv_probe in bond_handle_frame")
> Fixes: 9a72c2da690d ("bonding: fix div by zero while enslaving and transmitting")
> Fixes: ee6377147409 ("bonding: Simplify the xmit function for modes that use xmit_hash")
> Fixes: 429208aab9db ("net: bonding: add the READ_ONCE/WRITE_ONCE for outside lock accessing")
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> Cc: Jay Vosburgh <jv@jvosburgh.net>
Clashiko noted there is still a missing READ_ONCE annotation for
`usable_slaves->count` in bond_miimon_inspect(), but I think that is
better handled with a separate patch.

/P