6.8-stable review patch. If anyone has any objections, please let me know.
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From: Sebastian Andrzej Siewior bigeasy@linutronix.de
[ Upstream commit 9067eccdd7849dd120d5495dbd5a686fa6ed2c1a ]
The selftest for the driver sends a dummy packet and checks if the packet will be received properly as it should be. The regular TX path and the selftest can use the same network queue so locking is required and was missing in the selftest path. This was addressed in the commit cited below. Unfortunately locking the TX queue requires BH to be disabled which is not the case in selftest path which is invoked in process context. Lockdep should be complaining about this.
Use __netif_tx_lock_bh() for TX queue locking.
Fixes: c650e04898072 ("cxgb4: Fix race between loopback and normal Tx path") Reported-by: "John B. Wyatt IV" jwyatt@redhat.com Closes: https://lore.kernel.org/all/Zic0ot5aGgR-V4Ks@thinkpad2021/ Signed-off-by: Sebastian Andrzej Siewior bigeasy@linutronix.de Link: https://lore.kernel.org/r/20240429091147.YWAaal4v@linutronix.de Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/chelsio/cxgb4/sge.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/chelsio/cxgb4/sge.c b/drivers/net/ethernet/chelsio/cxgb4/sge.c index b5ff2e1a9975f..2285f2e87e689 100644 --- a/drivers/net/ethernet/chelsio/cxgb4/sge.c +++ b/drivers/net/ethernet/chelsio/cxgb4/sge.c @@ -2684,12 +2684,12 @@ int cxgb4_selftest_lb_pkt(struct net_device *netdev) lb->loopback = 1;
q = &adap->sge.ethtxq[pi->first_qset]; - __netif_tx_lock(q->txq, smp_processor_id()); + __netif_tx_lock_bh(q->txq);
reclaim_completed_tx(adap, &q->q, -1, true); credits = txq_avail(&q->q) - ndesc; if (unlikely(credits < 0)) { - __netif_tx_unlock(q->txq); + __netif_tx_unlock_bh(q->txq); return -ENOMEM; }
@@ -2724,7 +2724,7 @@ int cxgb4_selftest_lb_pkt(struct net_device *netdev) init_completion(&lb->completion); txq_advance(&q->q, ndesc); cxgb4_ring_tx_db(adap, &q->q, ndesc); - __netif_tx_unlock(q->txq); + __netif_tx_unlock_bh(q->txq);
/* wait for the pkt to return */ ret = wait_for_completion_timeout(&lb->completion, 10 * HZ);