airoha_qdma_get_tx_ets_stats() has two bugs:
- The hardware counters read via airoha_qdma_rr() are 32-bit values
but are stored in u64 locals and subtracted from u64 baselines. When
a 32-bit hardware counter wraps around, the subtraction produces a
large underflow value passed to _bstats_update().
- The baseline counters (cpu_tx_packets, fwd_tx_packets) are stored as
single per-device fields, but airoha_qdma_get_tx_ets_stats() is
called with different channel values (0-3). Each call reads a
different channel's hardware counter but overwrites the same
baseline, corrupting the delta computation for other channels.
Fix both by:
- Narrowing the counter locals and baselines to u32 so that 32-bit
unsigned subtraction handles wrap-around naturally.
- Grouping the baselines into a per-channel qos_stats array so each
channel tracks its own previous counter value independently.
- Splitting the delta addition into two statements so the first u32
delta is widened to u64 on assignment and the second is added in
u64 arithmetic, preventing overflow when both deltas are large.
Fixes: 20bf7d07c9 ("net: airoha: Add sched ETS offload support")
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://patch.msgid.link/20260725-airoha-ethtool-priv_flags-v12-2-5136a30b2157@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
8b9a508819