ESXi 5.x host fails with a purple diagnostic screen and reports the backtrace: VmMemCow_PShareRemoveHint@vmkernel#nover+0xa2 stack: 0x19ab7, 0xffff in VMware ESXi 5.1.x

Products

• VMware vSphere ESXi

Issue/Introduction

Symptoms:
An ESXi 5.1 (build 799733) host fails with a purple diagnostic screen and reports a backtrace similar to:

• 14T13:55:05.384Z cpu5:67852)0x41222431bb30:[0x418010300269]World_Panic@vmkernel#nover+0x184 stack: 0x323130326d375b1b, 0x412224
14T13:55:05.386Z cpu5:67852)0x41222431bd50:[0x418010300269]World_Panic@vmkernel#nover+0x184 stack: 0x41220036c020, 0x100004101,
14T13:55:05.389Z cpu5:67852)0x41222431bdd0:[0x4180102ca31b]VmMemCow_PShareRemoveHint@vmkernel#nover+0xa2 stack: 0x19ab7, 0xffff
14T13:55:05.391Z cpu5:67852)0x41222431be30:[0x4180102cd70a]VmMemCowPFrameRemoveHint@vmkernel#nover+0x6d stack: 0x410000000000,
14T13:55:05.393Z cpu5:67852)0x41222431bfa0:[0x4180102cef79]VmMemCowPShareFn@vmkernel#nover+0x548 stack: 0x41222431bff0, 0x41003
14T13:55:05.395Z cpu5:67852)0x41222431bff0:[0x4180102b13c4]VmAssistantProcessTask@vmkernel#nover+0x19f stack: 0x0, 0x0, 0x0, 0x
  
  
• 14T13:55:05.384Z cpu5:67852)0x41222431bb30:[0x418010300269]World_Panic@vmkernel#nover+0x184 stack: 0x323130326d375b1b, 0x412224
14T13:55:05.386Z cpu5:67852)0x41222431bd50:[0x418010300269]World_Panic@vmkernel#nover+0x184 stack: 0x41220036c020, 0x100004101,
14T13:55:05.389Z cpu5:67852)0x41222431bdd0:[0x4180102ca31b]VmMemCow_PShareRemoveHint@vmkernel#nover+0xa2 stack: 0x19ab7, 0xffff
14T13:55:05.391Z cpu5:67852)0x41222431be30:[0x4180102cd70a]VmMemCowPFrameRemoveHint@vmkernel#nover+0x6d stack: 0x410000000000,
14T13:55:05.393Z cpu5:67852)0x41222431bfa0:[0x4180102cef79]VmMemCowPShareFn@vmkernel#nover+0x548 stack: 0x41222431bff0, 0x41003
14T13:55:05.395Z cpu5:67852)0x41222431bff0:[0x4180102b13c4]VmAssistantProcessTask@vmkernel#nover+0x19f stack: 0x0, 0x0, 0x0, 0x
  
  
• 29T12:05:36.538Z cpu1:30150)pcpu:63 world:36075 name:"vmm6:SBCDF070" (V)
29T12:05:36.538Z cpu1:30150)@BlueScreen: #PF Exception 14 in world 30150:vmast.30149 IP 0x418034680946 addr 0x410401535420
29T12:05:36.539Z cpu1:30150)Code start: 0x418034600000 VMK uptime: 0:16:17:39.669
29T12:05:36.540Z cpu1:30150)0x41231719bda0:[0x418034680946]PShareHashTableWalk@vmkernel#nover+0x141 stack: 0x41231719bf68
29T12:05:36.541Z cpu1:30150)0x41231719be30:[0x41803468343f]PShare_LookupByKey@vmkernel#nover+0x14a stack: 0x410000000001
29T12:05:36.543Z cpu1:30150)0x41231719bfa0:[0x4180346cf0f2]VmMemCowPShareFn@vmkernel#nover+0x6c1 stack: 0x41231719bff0
29T12:05:36.544Z cpu1:30150)0x41231719bff0:[0x4180346b13c4]VmAssistantProcessTask@vmkernel#nover+0x19f stack: 0x0
29T12:05:36.545Z cpu1:30150)0x41231719bff8:[0x0]<unknown> stack: 0x0

Environment

VMware vSphere ESXi 5.1

Resolution

This is a known issue in VMware ESXi 5.1 and is resolved in patch ESXi510-201212401-BG (Build 914609). For more information, see VMware ESXi 5.1, Patch ESXi510-201212401-BG: Updates esx-base (2035777) and VMware ESXi 5.1, Patch Release ESXi510-201212001 (2035775).

To work around this issue, connect to each host in your environment using SSH and run this command:

esxcli system settings advanced set -o /BufferCache/MinZeroCopyBufferLength -i 512

To verify that the setting has been updated, run this command:

esxcli system settings advanced list --option /BufferCache/MinZeroCopyBufferLength

Additional Information

VMware ESXi 5.1, Patch Release ESXi510-201212001
VMware ESXi 5.1, Patch ESXi510-201212401-BG: Updates esx-base