ThunderX: TX failure unless checksum offload disabled

[Scott Burns]

[Impact]
Most attempts to use IPv6 on the ThunderX NIC will fail.

[Test Case]
Attempt an IPv6 TCP connection:

$ wget -6 'http://www.kernel.org/'

The connection will time out.

[Regression Risk]
The fix is upstream, and is limited to the ThunderX nicvf driver.

[Workaround]
Disable TX checksum offload:

$ ethtool -K eth0 tx off

[More Details]
The issue first appears in Linux 4.12. A fix from Cavium has been merged upstream:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/drivers/net/ethernet/cavium/thunder/nicvf_queues.c?id=fa6d7cb5d76cf0467c61420fc9238045aedfd379

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is missing log files that will aid in diagnosing the problem. While running an Ubuntu kernel (not a mainline or third-party kernel) please enter the following command in a terminal window:

apport-collect 1736593

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.

[Kleber Sacilotto de Souza (kleber-souza)]

This bug is awaiting verification that the kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-artful' to 'verification-done-artful'. If the problem still exists, change the tag 'verification-needed-artful' to 'verification-failed-artful'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

[Edward Vielmetti (edward-vielmetti)]

Thank you. We will be testing this new kernel at Packet and will report results.

[dann frazier (dannf)]

On Wed, Feb 14, 2018 at 8:53 AM, Edward Vielmetti
<email address hidden> wrote:
> Thank you. We will be testing this new kernel at Packet and will report
> results.

Thanks Edward. Please beware of LP: #1749040 as you test. We're not
seeing it with the latest build, but it is not yet root-caused.

  -dann

[Edward Vielmetti (edward-vielmetti)]

Thanks Dann. Scott is testing this and has found an additional issue, but we're not sure yet whether it's directly related or independent. He'll file a more detailed report or open another Launchpad as appropriate.

[Scott Burns (scott4000)]

I am glad to report that the problem has been resolved. The issues I saw with 4.13.0-35.39 during verification appear to be KPTI-related. After upgrading to 4.13.0-36.40, all is well.

Thanks to everyone that assisted with moving this forward.

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux - 4.13.0-36.40

---------------
linux (4.13.0-36.40) artful; urgency=medium

  * linux: 4.13.0-36.40 -proposed tracker (LP: #1750010)

  * Rebuild without "CVE-2017-5754 ARM64 KPTI fixes" patch set

linux (4.13.0-35.39) artful; urgency=medium

  * linux: 4.13.0-35.39 -proposed tracker (LP: #1748743)

  * CVE-2017-5715 (Spectre v2 Intel)
    - Revert "UBUNTU: SAUCE: turn off IBPB when full retpoline is present"
    - SAUCE: turn off IBRS when full retpoline is present
    - [Packaging] retpoline files must be sorted
    - [Packaging] pull in retpoline files

linux (4.13.0-34.37) artful; urgency=medium

  * linux: 4.13.0-34.37 -proposed tracker (LP: #1748475)

  * libata: apply MAX_SEC_1024 to all LITEON EP1 series devices (LP: #1743053)
    - libata: apply MAX_SEC_1024 to all LITEON EP1 series devices

  * KVM patches for s390x to provide facility bits 81 (ppa15) and 82 (bpb)
    (LP: #1747090)
    - KVM: s390: wire up bpb feature

  * artful 4.13 i386 kernels crash after memory hotplug remove (LP: #1747069)
    - Revert "mm, memory_hotplug: do not associate hotadded memory to zones until
      online"

  * CVE-2017-5715 (Spectre v2 Intel)
    - x86/feature: Enable the x86 feature to control Speculation
    - x86/feature: Report presence of IBPB and IBRS control
    - x86/enter: MACROS to set/clear IBRS and set IBPB
    - x86/enter: Use IBRS on syscall and interrupts
    - x86/idle: Disable IBRS entering idle and enable it on wakeup
    - x86/idle: Disable IBRS when offlining cpu and re-enable on wakeup
    - x86/mm: Set IBPB upon context switch
    - x86/mm: Only set IBPB when the new thread cannot ptrace current thread
    - x86/entry: Stuff RSB for entry to kernel for non-SMEP platform
    - x86/kvm: add MSR_IA32_SPEC_CTRL and MSR_IA32_PRED_CMD to kvm
    - x86/kvm: Set IBPB when switching VM
    - x86/kvm: Toggle IBRS on VM entry and exit
    - x86/spec_ctrl: Add sysctl knobs to enable/disable SPEC_CTRL feature
    - x86/spec_ctrl: Add lock to serialize changes to ibrs and ibpb control
    - x86/cpu/AMD: Add speculative control support for AMD
    - x86/microcode: Extend post microcode reload to support IBPB feature
    - KVM: SVM: Do not intercept new speculative control MSRs
    - x86/svm: Set IBRS value on VM entry and exit
    - x86/svm: Set IBPB when running a different VCPU
    - KVM: x86: Add speculative control CPUID support for guests
    - SAUCE: turn off IBPB when full retpoline is present

  * Artful 4.13 fixes for tun (LP: #1748846)
    - tun: call dev_get_valid_name() before register_netdevice()
    - tun: allow positive return values on dev_get_valid_name() call
    - tun/tap: sanitize TUNSETSNDBUF input

  * boot failure on AMD Raven + WestonXT (LP: #1742759)
    - SAUCE: drm/amdgpu: add atpx quirk handling (v2)

linux (4.13.0-33.36) artful; urgency=low

  * linux: 4.13.0-33.36 -proposed tracker (LP: #1746903)

  [ Stefan Bader ]
  * starting VMs causing retpoline4 to reboot (LP: #1747507) // CVE-2017-5715
    (Spectre v2 retpoline)
    - x86/retpoline: Fill RSB on context switch for affected CPUs
    - x86/retpoline: Add LFENCE to the retpoline/RSB filling RSB macros
    - x86/retpol...