[Qemu-devel] PCI passthrough of 40G ethernet interface (Openstack/KVM)

[jacob jacob]

Hi,

Seeing failures when trying to do PCI passthrough of Intel XL710 40G interface to KVM vm.

    0a:00.1 Ethernet controller: Intel Corporation Ethernet Controller XL710 for 40GbE QSFP+ (rev 01)

From dmesg on host:

[80326.559674] kvm: zapping shadow pages for mmio generation wraparound

[80327.271191] kvm [175994]: vcpu0 unhandled rdmsr: 0x1c9

[80327.271689] kvm [175994]: vcpu0 unhandled rdmsr: 0x1a6

[80327.272201] kvm [175994]: vcpu0 unhandled rdmsr: 0x1a7

[80327.272681] kvm [175994]: vcpu0 unhandled rdmsr: 0x3f6

[80327.376186] kvm [175994]: vcpu0 unhandled rdmsr: 0x606

The pci device is still available in the VM but stat transfer fails.

With the i40e driver, the data transfer fails.

 Relevant dmesg output:

 [   11.544088] i40e 0000:00:05.0 eth1: NIC Link is Up 40 Gbps Full Duplex, Flow Control: None

[   11.689178] i40e 0000:00:06.0 eth2: NIC Link is Up 40 Gbps Full Duplex, Flow Control: None

[   16.704071] ------------[ cut here ]------------

[   16.705053] WARNING: CPU: 1 PID: 0 at net/sched/sch_generic.c:303 dev_watchdog+0x23e/0x250()

[   16.705053] NETDEV WATCHDOG: eth1 (i40e): transmit queue 1 timed out

[   16.705053] Modules linked in: cirrus ttm drm_kms_helper i40e drm ppdev serio_raw i2c_piix4 virtio_net parport_pc ptp virtio_balloon crct10dif_pclmul pps_core parport pvpanic crc32_pclmul ghash_clmulni_intel virtio_blk crc32c_intel virtio_pci virtio_ring virtio ata_generic pata_acpi

[   16.705053] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 3.18.7-200.fc21.x86_64 #1

[   16.705053] Hardware name: Fedora Project OpenStack Nova, BIOS 1.7.5-20140709_153950- 04/01/2014

[   16.705053]  0000000000000000 2e5932b294d0c473 ffff88043fc83d48 ffffffff8175e686

[   16.705053]  0000000000000000 ffff88043fc83da0 ffff88043fc83d88 ffffffff810991d1

[   16.705053]  ffff88042958f5c0 0000000000000001 ffff88042865f000 0000000000000001

[   16.705053] Call Trace:

[   16.705053]  <IRQ>  [<ffffffff8175e686>] dump_stack+0x46/0x58

[   16.705053]  [<ffffffff810991d1>] warn_slowpath_common+0x81/0xa0

[   16.705053]  [<ffffffff81099245>] warn_slowpath_fmt+0x55/0x70

[   16.705053]  [<ffffffff8166e62e>] dev_watchdog+0x23e/0x250

[   16.705053]  [<ffffffff8166e3f0>] ? dev_graft_qdisc+0x80/0x80

[   16.705053]  [<ffffffff810fd52a>] call_timer_fn+0x3a/0x120

[   16.705053]  [<ffffffff8166e3f0>] ? dev_graft_qdisc+0x80/0x80

[   16.705053]  [<ffffffff810ff692>] run_timer_softirq+0x212/0x2f0

[   16.705053]  [<ffffffff8109d7a4>] __do_softirq+0x124/0x2d0

[   16.705053]  [<ffffffff8109db75>] irq_exit+0x125/0x130

[   16.705053]  [<ffffffff817681d8>] smp_apic_timer_interrupt+0x48/0x60

[   16.705053]  [<ffffffff817662bd>] apic_timer_interrupt+0x6d/0x80

[   16.705053]  <EOI>  [<ffffffff811005c8>] ? hrtimer_start+0x18/0x20

[   16.705053]  [<ffffffff8105ca96>] ? native_safe_halt+0x6/0x10

[   16.705053]  [<ffffffff810f81d3>] ? rcu_eqs_enter+0xa3/0xb0

[   16.705053]  [<ffffffff8101ec7f>] default_idle+0x1f/0xc0

[   16.705053]  [<ffffffff8101f64f>] arch_cpu_idle+0xf/0x20

[   16.705053]  [<ffffffff810dad35>] cpu_startup_entry+0x3c5/0x410

[   16.705053]  [<ffffffff8104a2af>] start_secondary+0x1af/0x1f0

[   16.705053] ---[ end trace 7bda53aeda558267 ]---

[   16.705053] i40e 0000:00:05.0 eth1: tx_timeout recovery level 1

[   16.705053] i40e 0000:00:05.0: i40e_vsi_control_tx: VSI seid 519 Tx ring 0 disable timeout

[   16.744198] i40e 0000:00:05.0: i40e_vsi_control_tx: VSI seid 520 Tx ring 64 disable timeout

[   16.779322] i40e 0000:00:05.0: i40e_ptp_init: added PHC on eth1

[   16.791819] i40e 0000:00:05.0: PF 40 attempted to control timestamp mode on port 1, which is owned by PF 1

[   16.933869] i40e 0000:00:05.0 eth1: NIC Link is Up 40 Gbps Full Duplex, Flow Control: None

[   18.853624] SELinux: initialized (dev tmpfs, type tmpfs), uses transition SIDs

[   22.720083] i40e 0000:00:05.0 eth1: tx_timeout recovery level 2

[   22.826993] i40e 0000:00:05.0: i40e_vsi_control_tx: VSI seid 519 Tx ring 0 disable timeout

[   22.935288] i40e 0000:00:05.0: i40e_vsi_control_tx: VSI seid 520 Tx ring 64 disable timeout

[   23.669555] i40e 0000:00:05.0: i40e_ptp_init: added PHC on eth1

[   23.682067] i40e 0000:00:05.0: PF 40 attempted to control timestamp mode on port 1, which is owned by PF 1

[   23.722423] i40e 0000:00:05.0 eth1: NIC Link is Up 40 Gbps Full Duplex, Flow Control: None

[   23.800206] i40e 0000:00:06.0: i40e_ptp_init: added PHC on eth2

[   23.813804] i40e 0000:00:06.0: PF 48 attempted to control timestamp mode on port 0, which is owned by PF 0

[   23.855275] i40e 0000:00:06.0 eth2: NIC Link is Up 40 Gbps Full Duplex, Flow Control: None

[   38.720091] i40e 0000:00:05.0 eth1: tx_timeout recovery level 3

[   38.725844] random: nonblocking pool is initialized

[   38.729874] i40e 0000:00:06.0: HMC error interrupt

[   38.733425] i40e 0000:00:06.0: i40e_vsi_control_tx: VSI seid 518 Tx ring 0 disable timeout

[   38.738886] i40e 0000:00:06.0: i40e_vsi_control_tx: VSI seid 521 Tx ring 64 disable timeout

[   39.689569] i40e 0000:00:06.0: i40e_ptp_init: added PHC on eth2

[   39.704197] i40e 0000:00:06.0: PF 48 attempted to control timestamp mode on port 0, which is owned by PF 0

[   39.746879] i40e 0000:00:06.0 eth2: NIC Link is Down

[   39.838356] i40e 0000:00:05.0: i40e_ptp_init: added PHC on eth1

[   39.851788] i40e 0000:00:05.0: PF 40 attempted to control timestamp mode on port 1, which is owned by PF 1

[   39.892822] i40e 0000:00:05.0 eth1: NIC Link is Down

[   43.011610] i40e 0000:00:06.0 eth2: NIC Link is Up 40 Gbps Full Duplex, Flow Control: None

[   43.059976] i40e 0000:00:05.0 eth1: NIC Link is Up 40 Gbps Full Duplex, Flow Control: None

Would appreciate any information on how to debug this issue further and if the "unhandled rdmsr" logs from KVM indicate some issues with the device passthrough.

Thanks

Jacob