ESXi host PSOD with "#PF Exception 14" in world "CAM taskq" due to BMC Virtual Media

Products

• VMware vSphere ESXi

Issue/Introduction

• An ESXi 8.x host experiences a Purple Screen of Death (PSOD) with a backtrace similar to the following:

  YYYY-MM-DDTHH:MM:SS cpu1:2098002)@BlueScreen: #PF Exception 14 in world 2098002:CAM taskq IP 0x0 addr 0x0

• The backtrace includes references to
  • taskqueue_run_locked
  • taskqueue_thread_loop
  • vmkWorldFunc
• Note: The current BMC version can be verified by executing the following command directly on the ESXi host:
  esxcfg-info -a | grep "BMC Version"
• ESXi Servers running older BMC firmware versions. This issue has been specifically observed on BMC versions 3.68 and 4.40.

Environment

• VMware vSphere ESXi 7.x
• VMware vSphere ESXi 8.x

Cause

This issue is caused by a race condition within the taskqueue_run_locked thread of the ESXi kernel. The condition is triggered when the Baseboard Management Controller (BMC) Virtual CD-ROM/Media is attached and detached rapidly. The thread attempts to process a corrupted or null task, leading to the #PF Exception 14 (Page Fault) crash.

 

Resolution

The issue is resolved by updating the server's BMC/IPMI firmware to the latest version provided by the hardware vendor.

Workaround: Disable or avoid using the BMC Virtual Media / Virtual CD-ROM features until the firmware can be updated.