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The tx->dropped_pkt counter is a 64-bit integer that is incremented directly. On 32-bit architectures, this operation is not atomic and can lead to read/write tearing if a reader accesses the counter during the update. This can result in incorrect values being reported for dropped packets. To prevent this potential data corruption, wrap the increment operation with u64_stats_update_begin() and u64_stats_update_end(). This ensures that updates to the 64-bit counter are atomic, even on 32-bit systems, by using a sequence lock. The u64_stats_sync API requires the writer to have exclusive access, which is already provided in this context by the network stack's serialization of the transmit path (net_device_ops::ndo_start_xmit [1]) for a given queue. [1]: https://www.kernel.org/doc/Documentation/networking/netdevices.txt Signed-off-by: Max Yuan <maxyuan@google.com> Reviewed-by: Jordan Rhee <jordanrhee@google.com> Signed-off-by: Harshitha Ramamurthy <hramamurthy@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>