[PATCH 5.19 151/207] ice: Fix ice_xdp_xmit() when XDP TX queue number is not sufficient

From: Greg Kroah-Hartman
Date: Mon Sep 26 2022 - 07:56:47 EST


From: Larysa Zaremba <larysa.zaremba@xxxxxxxxx>

[ Upstream commit 114f398d48c571bb628187a7b2dd42695156781f ]

The original patch added the static branch to handle the situation,
when assigning an XDP TX queue to every CPU is not possible,
so they have to be shared.

However, in the XDP transmit handler ice_xdp_xmit(), an error was
returned in such cases even before static condition was checked,
thus making queue sharing still impossible.

Fixes: 22bf877e528f ("ice: introduce XDP_TX fallback path")
Signed-off-by: Larysa Zaremba <larysa.zaremba@xxxxxxxxx>
Reviewed-by: Alexander Lobakin <alexandr.lobakin@xxxxxxxxx>
Link: https://lore.kernel.org/r/20220919134346.25030-1-larysa.zaremba@xxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/intel/ice/ice_txrx.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/ice/ice_txrx.c b/drivers/net/ethernet/intel/ice/ice_txrx.c
index 836dce840712..97453d1dfafe 100644
--- a/drivers/net/ethernet/intel/ice/ice_txrx.c
+++ b/drivers/net/ethernet/intel/ice/ice_txrx.c
@@ -610,7 +610,7 @@ ice_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames,
if (test_bit(ICE_VSI_DOWN, vsi->state))
return -ENETDOWN;

- if (!ice_is_xdp_ena_vsi(vsi) || queue_index >= vsi->num_xdp_txq)
+ if (!ice_is_xdp_ena_vsi(vsi))
return -ENXIO;

if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK))
@@ -621,6 +621,9 @@ ice_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames,
xdp_ring = vsi->xdp_rings[queue_index];
spin_lock(&xdp_ring->tx_lock);
} else {
+ /* Generally, should not happen */
+ if (unlikely(queue_index >= vsi->num_xdp_txq))
+ return -ENXIO;
xdp_ring = vsi->xdp_rings[queue_index];
}

--
2.35.1