[dpdk-dev] IXGBE, IOMMU DMAR DRHD handling fault issue

Ravi Kerur rkerur at gmail.com
Mon Feb 12 23:00:41 CET 2018


On Mon, Feb 12, 2018 at 2:13 AM, Burakov, Anatoly <anatoly.burakov at intel.com
> wrote:

> On 10-Feb-18 5:53 PM, Ravi Kerur wrote:
>
>
>>
>> On Sat, Feb 10, 2018 at 2:58 AM, Burakov, Anatoly <
>> anatoly.burakov at intel.com <mailto:anatoly.burakov at intel.com>> wrote:
>>
>>     On 29-Jan-18 10:35 PM, Ravi Kerur wrote:
>>
>>         Hi Burakov,
>>
>>         When using vfio-pci on host both VF and PF interfaces works fine
>>         with dpdk i.e. I don't see DMAR fault messages anymore. However,
>>         when I attach a VF interface to a VM and start DPDK with
>>         vfio-pci inside VM I still see DMAR fault messages on host. Both
>>         host and VM are booted with 'intel-iommu=on' on GRUB. Ping from
>>         VM with DPDK/vfio-pci doesn't work (I think it's expected
>>         because of DMAR faults), however, when VF interface uses ixgbevf
>>         driver ping works.
>>
>>         Following are some details
>>
>>         /*****************On VM***************/
>>         dpdk-devbind -s
>>
>>         Network devices using DPDK-compatible driver
>>         ============================================
>>         0000:00:07.0 '82599 Ethernet Controller Virtual Function'
>>         drv=vfio-pci unused=ixgbevf
>>
>>         Network devices using kernel driver
>>         ===================================
>>         0000:03:00.0 'Device 1041' if=eth0 drv=virtio-pci
>>         unused=vfio-pci *Active*
>>         0000:04:00.0 'Device 1041' if=eth1 drv=virtio-pci unused=vfio-pci
>>         0000:05:00.0 'Device 1041' if=eth2 drv=virtio-pci unused=vfio-pci
>>
>>         Other network devices
>>         =====================
>>         <none>
>>
>>         Crypto devices using DPDK-compatible driver
>>         ===========================================
>>         <none>
>>
>>         Crypto devices using kernel driver
>>         ==================================
>>         <none>
>>
>>         Other crypto devices
>>         ====================
>>         <none>
>>
>>
>>         00:07.0 Ethernet controller: Intel Corporation 82599 Ethernet
>>         Controller Virtual Function (rev 01)
>>                   Subsystem: Intel Corporation 82599 Ethernet Controller
>>         Virtual Function
>>                   Control: I/O- Mem+ BusMaster- SpecCycle- MemWINV-
>>         VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
>>                   Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast
>>          >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
>>                   Region 0: Memory at fda00000 (64-bit, prefetchable)
>>         [size=16K]
>>                   Region 3: Memory at fda04000 (64-bit, prefetchable)
>>         [size=16K]
>>                   Capabilities: [70] MSI-X: Enable+ Count=3 Masked-
>>                           Vector table: BAR=3 offset=00000000
>>                           PBA: BAR=3 offset=00002000
>>                   Capabilities: [a0] Express (v1) Root Complex
>>         Integrated Endpoint, MSI 00
>>                           DevCap: MaxPayload 128 bytes, PhantFunc 0
>>                                   ExtTag- RBE-
>>                           DevCtl: Report errors: Correctable- Non-Fatal-
>>         Fatal- Unsupported-
>>                                   RlxdOrd- ExtTag- PhantFunc- AuxPwr-
>>         NoSnoop-
>>                                   MaxPayload 128 bytes, MaxReadReq 128
>> bytes
>>                           DevSta: CorrErr- UncorrErr- FatalErr-
>>         UnsuppReq- AuxPwr- TransPend-
>>                   Capabilities: [100 v1] Advanced Error Reporting
>>                           UESta:  DLP- SDES- TLP- FCP- CmpltTO-
>>         CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
>>                           UEMsk:  DLP- SDES- TLP- FCP- CmpltTO-
>>         CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
>>                           UESvrt: DLP- SDES- TLP- FCP- CmpltTO-
>>         CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
>>                           CESta:  RxErr- BadTLP- BadDLLP- Rollover-
>>         Timeout- NonFatalErr-
>>                           CEMsk:  RxErr- BadTLP- BadDLLP- Rollover-
>>         Timeout- NonFatalErr-
>>                           AERCap: First Error Pointer: 00, GenCap-
>>         CGenEn- ChkCap- ChkEn-
>>                   Kernel driver in use: vfio-pci
>>                   Kernel modules: ixgbevf
>>
>>         /***************on Host*************/
>>         dmesg | grep DMAR
>>         ...
>>         [  978.268143] DMAR: DRHD: handling fault status reg 2
>>         [  978.268147] DMAR: [DMA Read] *Request device [04:10.0]* fault
>>         addr 33a128000 [fault reason 06] PTE Read access is not set
>>         [ 1286.677726] DMAR: DRHD: handling fault status reg 102
>>         [ 1286.677730] DMAR: [DMA Read] Request device [04:10.0] fault
>>         addr fb663000 [fault reason 06] PTE Read access is not set
>>         [ 1676.436145] DMAR: DRHD: handling fault status reg 202
>>         [ 1676.436149] DMAR: [DMA Read] Request device [04:10.0] fault
>>         addr 33a128000 [fault reason 06] PTE Read access is not set
>>         [ 1734.433649] DMAR: DRHD: handling fault status reg 302
>>         [ 1734.433652] DMAR: [DMA Read] Request device [04:10.0] fault
>>         addr 33a128000 [fault reason 06] PTE Read access is not set
>>         [ 2324.428938] DMAR: DRHD: handling fault status reg 402
>>         [ 2324.428942] DMAR: [DMA Read] Request device [04:10.0] fault
>>         addr 7770c000 [fault reason 06] PTE Read access is not set
>>         [ 2388.553640] DMAR: DRHD: handling fault status reg 502
>>         [ 2388.553643] DMAR: [DMA Read] *Request device [04:10.0]* fault
>>         addr 33a128000 [fault reason 06] PTE Read access is not set
>>
>>
>>
>>     Going back to this, i would like to suggest run a few tests to
>>     ensure that we have all information that we can gather.
>>
>>     First of all, i'm assuming that you're using native ixgbe Linux
>>     driver on the host, and that you're only passing through the VF
>>     device to the VM using VFIO. Is my understanding correct here?
>>
>>     Now, let's forget about the iommu=pt and igb_uio for a moment. Boot
>>     both your host and your VM with iommu=on and intel_iommu=on (or
>>     whatever command-line enables full IOMMU support on both host and
>>     guest) and do the same tests you've done before. Do you still see
>>     your issues?
>>
>>     It would also be very useful to also try native Linux kernel driver
>>     on the guest *with traffic forwarding* and see how it works in your
>>     VM. Therefore i would suggest you to compile DPDK with PCAP support,
>>     bind your (VM) interface to native Linux driver, and use the
>>     interface via our pcap driver (creating a vdev should do the trick -
>>     please refer to PCAP PMD documentation [1]). Simple forwarding test
>>     should be enough - just make sure to pass traffic to and from DPDK
>>     in both cases, and that it doesn't give you any DMAR errors.
>>
>>     We can go from there.
>>
>>
>> Let me just give you what has been tested and working/nonworking
>> scenarios. Some of your questions might get answered as well. Test bed is
>> very simple with 2 VF's created under IXGBE PF on host with one VF
>> interface added to ovs-bridge on host and another VF interface given to
>> guest. Test connectivity between VF's via ping.
>>
>> Host and guest -- Kernel 4.9
>> Host -- Qemu 2.11.50 (tried both released 2.11 and tip of the git
>> (2.11.50))
>> DPDK -- 17.05.1 on host and guest
>> Host and guest -- booted with GRUB intel_iommu=on (which enables IOMMU).
>> Have tried with "iommu=on and intel_iommu=on" as well, but iommu=on is not
>> needed when intel_iommu=on is set.
>>
>> Test-scenario-1: Host -- ixgbe_vf driver, Guest ixgbe_vf driver ping works
>> Test-scenario-2: Host -- DPDK vfio-pci driver, Guest ixgbe_vf driver ping
>> works
>> Test-scenario-3: Host -- DPDK vfio-pci driver, Guest DPDK vfio-pci
>> driver, DMAR errors seen on host, ping doesn't work
>>
>
> OK, that makes it clearer, thanks. Does the third scenario work in other
> DPDK versions?


No. Tried 16.11 same issue on guest and works fine on host.

>
>
>
>> DPDK works fine on host with vfio-pci, however, has issues when used
>> inside the guest. Please let me know if more information is needed.
>>
>> Thanks,
>> Ravi
>>
>>     [1] http://dpdk.org/doc/guides/nics/pcap_ring.html
>>     <http://dpdk.org/doc/guides/nics/pcap_ring.html>
>>
>>     --     Thanks,
>>     Anatoly
>>
>>
>>
>
> --
> Thanks,
> Anatoly
>


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