From eed913f6919e253f35d454b2f115f2a4db2b741a Mon Sep 17 00:00:00 2001 From: Akihiko Odaki Date: Fri, 28 Oct 2022 22:00:00 +0900 Subject: [PATCH 1/2] e1000e: Fix TX dispatch condition e1000_xmit_frame is expected to stop the queue and dispatch frames to hardware if there is not sufficient space for the next frame in the buffer, but sometimes it failed to do so because the estimated maximum size of frame was wrong. As the consequence, the later invocation of e1000_xmit_frame failed with NETDEV_TX_BUSY, and the frame in the buffer remained forever, resulting in a watchdog failure. This change fixes the estimated size by making it match with the condition for NETDEV_TX_BUSY. Apparently, the old estimation failed to account for the following lines which determines the space requirement for not causing NETDEV_TX_BUSY: ``` /* reserve a descriptor for the offload context */ if ((mss) || (skb->ip_summed == CHECKSUM_PARTIAL)) count++; count++; count += DIV_ROUND_UP(len, adapter->tx_fifo_limit); ``` This issue was found when running http-stress02 test included in Linux Test Project 20220930 on QEMU with the following commandline: ``` qemu-system-x86_64 -M q35,accel=kvm -m 8G -smp 8 -drive if=virtio,format=raw,file=root.img,file.locking=on -device e1000e,netdev=netdev -netdev tap,script=ifup,downscript=no,id=netdev ``` Fixes: bc7f75fa9788 ("[E1000E]: New pci-express e1000 driver (currently for ICH9 devices only)") Signed-off-by: Akihiko Odaki Tested-by: Gurucharan G (A Contingent worker at Intel) Tested-by: Naama Meir Signed-off-by: Tony Nguyen --- drivers/net/ethernet/intel/e1000e/netdev.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c index 49e926959ad3..55cf2f62bb30 100644 --- a/drivers/net/ethernet/intel/e1000e/netdev.c +++ b/drivers/net/ethernet/intel/e1000e/netdev.c @@ -5936,9 +5936,9 @@ static netdev_tx_t e1000_xmit_frame(struct sk_buff *skb, e1000_tx_queue(tx_ring, tx_flags, count); /* Make sure there is space in the ring for the next send. */ e1000_maybe_stop_tx(tx_ring, - (MAX_SKB_FRAGS * + ((MAX_SKB_FRAGS + 1) * DIV_ROUND_UP(PAGE_SIZE, - adapter->tx_fifo_limit) + 2)); + adapter->tx_fifo_limit) + 4)); if (!netdev_xmit_more() || netif_xmit_stopped(netdev_get_tx_queue(netdev, 0))) { From 28e96556baca7056d11d9fb3cdd0aba4483e00d8 Mon Sep 17 00:00:00 2001 From: Akihiko Odaki Date: Fri, 25 Nov 2022 22:30:31 +0900 Subject: [PATCH 2/2] igb: Allocate MSI-X vector when testing Without this change, the interrupt test fail with MSI-X environment: $ sudo ethtool -t enp0s2 offline [ 43.921783] igb 0000:00:02.0: offline testing starting [ 44.855824] igb 0000:00:02.0 enp0s2: igb: enp0s2 NIC Link is Down [ 44.961249] igb 0000:00:02.0 enp0s2: igb: enp0s2 NIC Link is Up 1000 Mbps Full Duplex, Flow Control: RX/TX [ 51.272202] igb 0000:00:02.0: testing shared interrupt [ 56.996975] igb 0000:00:02.0 enp0s2: igb: enp0s2 NIC Link is Up 1000 Mbps Full Duplex, Flow Control: RX/TX The test result is FAIL The test extra info: Register test (offline) 0 Eeprom test (offline) 0 Interrupt test (offline) 4 Loopback test (offline) 0 Link test (on/offline) 0 Here, "4" means an expected interrupt was not delivered. To fix this, route IRQs correctly to the first MSI-X vector by setting IVAR_MISC. Also, set bit 0 of EIMS so that the vector will not be masked. The interrupt test now runs properly with this change: $ sudo ethtool -t enp0s2 offline [ 42.762985] igb 0000:00:02.0: offline testing starting [ 50.141967] igb 0000:00:02.0: testing shared interrupt [ 56.163957] igb 0000:00:02.0 enp0s2: igb: enp0s2 NIC Link is Up 1000 Mbps Full Duplex, Flow Control: RX/TX The test result is PASS The test extra info: Register test (offline) 0 Eeprom test (offline) 0 Interrupt test (offline) 0 Loopback test (offline) 0 Link test (on/offline) 0 Fixes: 4eefa8f01314 ("igb: add single vector msi-x testing to interrupt test") Signed-off-by: Akihiko Odaki Reviewed-by: Maciej Fijalkowski Tested-by: Gurucharan G (A Contingent worker at Intel) Signed-off-by: Tony Nguyen --- drivers/net/ethernet/intel/igb/igb_ethtool.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/net/ethernet/intel/igb/igb_ethtool.c b/drivers/net/ethernet/intel/igb/igb_ethtool.c index e5f3e7680dc6..ff911af16a4b 100644 --- a/drivers/net/ethernet/intel/igb/igb_ethtool.c +++ b/drivers/net/ethernet/intel/igb/igb_ethtool.c @@ -1413,6 +1413,8 @@ static int igb_intr_test(struct igb_adapter *adapter, u64 *data) *data = 1; return -1; } + wr32(E1000_IVAR_MISC, E1000_IVAR_VALID << 8); + wr32(E1000_EIMS, BIT(0)); } else if (adapter->flags & IGB_FLAG_HAS_MSI) { shared_int = false; if (request_irq(irq,