[PATCH 5.12 324/384] sfc: farch: fix TX queue lookup in TX event handling

From: Greg Kroah-Hartman
Date: Mon May 10 2021 - 08:50:09 EST


From: Edward Cree <ecree.xilinx@xxxxxxxxx>

commit 83b09a1807415608b387c7bc748d329fefc5617e upstream.

We're starting from a TXQ label, not a TXQ type, so
efx_channel_get_tx_queue() is inappropriate (and could return NULL,
leading to panics).

Fixes: 12804793b17c ("sfc: decouple TXQ type from label")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Edward Cree <ecree.xilinx@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/sfc/farch.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

--- a/drivers/net/ethernet/sfc/farch.c
+++ b/drivers/net/ethernet/sfc/farch.c
@@ -835,14 +835,14 @@ efx_farch_handle_tx_event(struct efx_cha
/* Transmit completion */
tx_ev_desc_ptr = EFX_QWORD_FIELD(*event, FSF_AZ_TX_EV_DESC_PTR);
tx_ev_q_label = EFX_QWORD_FIELD(*event, FSF_AZ_TX_EV_Q_LABEL);
- tx_queue = efx_channel_get_tx_queue(
- channel, tx_ev_q_label % EFX_MAX_TXQ_PER_CHANNEL);
+ tx_queue = channel->tx_queue +
+ (tx_ev_q_label % EFX_MAX_TXQ_PER_CHANNEL);
efx_xmit_done(tx_queue, tx_ev_desc_ptr);
} else if (EFX_QWORD_FIELD(*event, FSF_AZ_TX_EV_WQ_FF_FULL)) {
/* Rewrite the FIFO write pointer */
tx_ev_q_label = EFX_QWORD_FIELD(*event, FSF_AZ_TX_EV_Q_LABEL);
- tx_queue = efx_channel_get_tx_queue(
- channel, tx_ev_q_label % EFX_MAX_TXQ_PER_CHANNEL);
+ tx_queue = channel->tx_queue +
+ (tx_ev_q_label % EFX_MAX_TXQ_PER_CHANNEL);

netif_tx_lock(efx->net_dev);
efx_farch_notify_tx_desc(tx_queue);