6.5-stable review patch. If anyone has any objections, please let me know.
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From: Vinicius Costa Gomes vinicius.gomes@intel.com
[ Upstream commit cb47b1f679c4d83a5fa5f1852e472f844e41a3da ]
When an XDP redirect happens before the link is ready, that transmission will not finish and will timeout, causing an adapter reset. If the redirects do not stop, the adapter will not stop resetting.
Wait for the driver to signal that there's a carrier before allowing transmissions to proceed.
Previous code was relying that when __IGC_DOWN is cleared, the NIC is ready to transmit as all the queues are ready, what happens is that the carrier presence will only be signaled later, after the watchdog workqueue has a chance to run. And during this interval (between clearing __IGC_DOWN and the watchdog running) if any transmission happens the timeout is emitted (detected by igc_tx_timeout()) which causes the reset, with the potential for the infinite loop.
Fixes: 4ff320361092 ("igc: Add support for XDP_REDIRECT action") Reported-by: Ferenc Fejes ferenc.fejes@ericsson.com Closes: https://lore.kernel.org/netdev/0caf33cf6adb3a5bf137eeaa20e89b167c9986d5.came... Signed-off-by: Vinicius Costa Gomes vinicius.gomes@intel.com Tested-by: Ferenc Fejes ferenc.fejes@ericsson.com Reviewed-by: Maciej Fijalkowski maciej.fijalkowski@intel.com Tested-by: Naama Meir naamax.meir@linux.intel.com Signed-off-by: Tony Nguyen anthony.l.nguyen@intel.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/intel/igc/igc_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c index 6f557e843e495..4e23b821c39ba 100644 --- a/drivers/net/ethernet/intel/igc/igc_main.c +++ b/drivers/net/ethernet/intel/igc/igc_main.c @@ -6433,7 +6433,7 @@ static int igc_xdp_xmit(struct net_device *dev, int num_frames, struct igc_ring *ring; int i, drops;
- if (unlikely(test_bit(__IGC_DOWN, &adapter->state))) + if (unlikely(!netif_carrier_ok(dev))) return -ENETDOWN;
if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK))