[PATCH 6.6 165/254] be2net: fix data race in be_get_new_eqd

Greg Kroah-Hartman
2026-01-28T15:35:31Z

From: David Yang <mmyangfl@gmail.com>

[ Upstream commit 302e5b481caa7b3d11ec0e058434c1fc95195e50 ]

In be_get_new_eqd(), statistics of pkts, protected by u64_stats_sync, are
read and accumulated in ignorance of possible u64_stats_fetch_retry()
events. Before the commit in question, these statistics were retrieved
one by one directly from queues. Fix this by reading them into temporary
variables first.

Fixes: 209477704187 ("be2net: set interrupt moderation for Skyhawk-R using EQ-DB")
Signed-off-by: David Yang <mmyangfl@gmail.com>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Link: https://patch.msgid.link/20260119153440.1440578-1-mmyangfl@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/emulex/benet/be_main.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/emulex/benet/be_main.c b/drivers/net/ethernet/emulex/benet/be_main.c
index 011c8cc8429e3..2ed1e290f9d78 100644
--- a/drivers/net/ethernet/emulex/benet/be_main.c
+++ b/drivers/net/ethernet/emulex/benet/be_main.c
@@ -2141,7 +2141,7 @@ static int be_get_new_eqd(struct be_eq_obj *eqo)
struct be_aic_obj *aic;
struct be_rx_obj *rxo;
struct be_tx_obj *txo;
- u64 rx_pkts = 0, tx_pkts = 0;
+ u64 rx_pkts = 0, tx_pkts = 0, pkts;
ulong now;
u32 pps, delta;
int i;
@@ -2157,15 +2157,17 @@ static int be_get_new_eqd(struct be_eq_obj *eqo)
for_all_rx_queues_on_eq(adapter, eqo, rxo, i) {
do {
start = u64_stats_fetch_begin(&rxo->stats.sync);
- rx_pkts += rxo->stats.rx_pkts;
+ pkts = rxo->stats.rx_pkts;
} while (u64_stats_fetch_retry(&rxo->stats.sync, start));
+ rx_pkts += pkts;
}

for_all_tx_queues_on_eq(adapter, eqo, txo, i) {
do {
start = u64_stats_fetch_begin(&txo->stats.sync);
- tx_pkts += txo->stats.tx_reqs;
+ pkts = txo->stats.tx_reqs;
} while (u64_stats_fetch_retry(&txo->stats.sync, start));
+ tx_pkts += pkts;
}

/* Skip, if wrapped around or first calculation */
--
2.51.0