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Document this, since a plain barrier without a comment is hard to interpret. Signed-off-by: Kai Kuang --- net/dsa/user.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/net/dsa/user.c b/net/dsa/user.c index cfad269be75c..96393d4b5da1 100644 --- a/net/dsa/user.c +++ b/net/dsa/user.c @@ -3435,6 +3435,10 @@ static void dsa_conduit_lag_leave(struct net_device *conduit, * physical CPU port */ lag_dev->dsa_ptr = new_cpu_dp; + /* Ensure the new dp->cpu_dp values are visible to concurrent + * RX path readers of lag_dev->dsa_ptr before the pointer + * itself becomes visible + */ wmb(); } else { /* If the LAG DSA conduit has no ports left, migrate back all -- 2.25.1 No virus found Checked by Hillstone Network AntiVirus