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Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , dev@openvswitch.org, linux-kernel@vger.kernel.org Subject: [PATCH net-next v2 4/7] net: openvswitch: fix load tearing with u64_stats Date: Sat, 24 Jan 2026 00:21:36 +0800 Message-ID: <20260123162159.2877941-5-mmyangfl@gmail.com> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260123162159.2877941-1-mmyangfl@gmail.com> References: <20260123162159.2877941-1-mmyangfl@gmail.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit On 64bit arches, struct u64_stats_sync is empty and provides no help against load/store tearing. struct copying should not be considered tear-free. Use u64_stats_reads() instead. Signed-off-by: David Yang --- net/openvswitch/datapath.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c index d5b6e2002bc1..8ba94df7f942 100644 --- a/net/openvswitch/datapath.c +++ b/net/openvswitch/datapath.c @@ -770,7 +770,8 @@ static void get_dp_stats(const struct datapath *dp, struct ovs_dp_stats *stats, do { start = u64_stats_fetch_begin(&percpu_stats->syncp); - local_stats = *percpu_stats; + u64_stats_reads(&local_stats, percpu_stats, + sizeof(local_stats)); } while (u64_stats_fetch_retry(&percpu_stats->syncp, start)); stats->n_hit += local_stats.n_hit; -- 2.51.0