This is a note to let you know that I've just added the patch titled
cxgb4: Properly lock TX queue for the selftest.
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
cxgb4-properly-lock-tx-queue-for-the-selftest.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit f86a6d2c1fadfc4771cc75ab393e52ded1b18e68
Author: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
Date: Mon Apr 29 11:11:47 2024 +0200
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" <jwyatt@xxxxxxxxxx>
Closes: https://lore.kernel.org/all/Zic0ot5aGgR-V4Ks@thinkpad2021/
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20240429091147.YWAaal4v@xxxxxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/ethernet/chelsio/cxgb4/sge.c b/drivers/net/ethernet/chelsio/cxgb4/sge.c
index fa5b596ff23a1..a074e9d44277f 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/sge.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/sge.c
@@ -2682,12 +2682,12 @@ 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;
}
@@ -2722,7 +2722,7 @@ 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);
