From ea6213141ec4b27f9bd4b1cb9030f3e94b58a901 Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Mon, 29 Apr 2024 11:11:47 +0200 Subject: [PATCH] cxgb4: Properly lock TX queue for the selftest. [ 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" Closes: https://lore.kernel.org/all/Zic0ot5aGgR-V4Ks@thinkpad2021/ Signed-off-by: Sebastian Andrzej Siewior Link: https://lore.kernel.org/r/20240429091147.YWAaal4v@linutronix.de Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- 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 ccb6bd002b20..89917dde0e22 100644 --- a/drivers/net/ethernet/chelsio/cxgb4/sge.c +++ b/drivers/net/ethernet/chelsio/cxgb4/sge.c @@ -2678,12 +2678,12 @@ 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; } @@ -2718,7 +2718,7 @@ 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);