System got hung while trying to add/delete the SAN devices repeateadly

Solution Verified - Updated -


  • System got hung while trying to test the addition/deletion of the SAN devices using following steps:

Steps to Reproduce:
1. Boot on the 6.6 kernel
2. Inject faults on the fabric layer and disable/enable targets ports repeatedly
3. Keep rescanning the SAN devices using following script:

    #!/bin/sh -ex
    while true; do
    date -r -a --hosts=7,8 -a --hosts=7,8
    sleep 1

4. System hangs with following processes in UN (uninterruptible) state:

    crash> ps -m |grep UN
    [0 05:11:58.719] [UN]  PID: 26788  TASK: ffff88033a868040  CPU: 3   COMMAND: "rescan-scsi-bus"
    [0 05:11:58.804] [UN]  PID: 16227  TASK: ffff880339604ab0  CPU: 1   COMMAND: "sysfsd"
    [0 05:11:58.750] [UN]  PID: 604    TASK: ffff880336ba8040  CPU: 4   COMMAND: "fc_wq_7"
    [0 05:12:28.276] [UN]  PID: 603    TASK: ffff880336ba8ab0  CPU: 3   COMMAND: "scsi_wq_7"


  • Red Hat Enterprise Linux 6.6
  • Kernel-2.6.32-504.16.2.el6.x86_64
  • Emulex FC HBA

Subscriber exclusive content

A Red Hat subscription provides unlimited access to our knowledgebase, tools, and much more.

Current Customers and Partners

Log in for full access

Log In

New to Red Hat?

Learn more about Red Hat subscriptions

Using a Red Hat product through a public cloud?

How to access this content