The log files are flooded with "xhci_hcd WARN" messages.

Solution Verified - Updated -


  • The log files, both /var/log/messages and dmesg, are flooded with message like :
kernel: xhci_hcd XXXX: WARN Event TRB for slot 1 ep 4 with no TDs queued?

where XXXX is a PCI device ID.


  • Observed on :

    • RHEL 6
    • RHEL 7
  • Observed on the following kernel versions :

    • 2.6.32-504.12.2.el6.x86_64
    • 3.10.0-514.26.2.el7.x86_64
    • 3.10.0-693.el7.x86_64
  • This issue is observed on servers using USB Smart-card Reader.

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