VMware ESXi 6.x host experiences a purple diagnostic screen

Products

VMware vSphere ESXi

Issue/Introduction

Before the crash, we have COW copy failed log spew:

ESC[7m2015-10-07T12:38:02.459Z cpu5:498764)WARNING: VmMemPf: vm 498729: 654: COW copy failed: pgNum=0x23de9, mpn=0x3fffffffffESC[0m

Followed by the PSOD:

2015-10-07T12:38:02.515Z cpu10:33172)@BlueScreen: PCPU 5: no heartbeat (2/2 IPIs received)

2015-10-07T12:38:02.516Z cpu10:33172)Code start: 0x418038000000 VMK uptime: 5:18:04:19.074

2015-10-07T12:38:02.516Z cpu10:33172)Saved backtrace from: pcpu 5 Heartbeat NMI

2015-10-07T12:38:02.516Z cpu10:33172)0x4391a261b858:[0x4180383433aa]vsnprintfPutChar@vmkernel#nover+0x16 stack: 0x4391a261b895

2015-10-07T12:38:02.516Z cpu10:33172)0x4391a261b860:[0x418038343b6d]Printf_WithFunc@vmkernel#nover+0x7c1 stack: 0x4391a261be01

2015-10-07T12:38:02.517Z cpu10:33172)0x4391a261b960:[0x418038344093]vsnprintf@vmkernel#nover+0x33 stack: 0x4180383a356d

2015-10-07T12:38:02.517Z cpu10:33172)0x4391a261b980:[0x41803809b992]vmk_StringVFormat@vmkernel#nover+0x4a stack: 0x4391a261ba20

2015-10-07T12:38:02.517Z cpu10:33172)0x4391a261b9a0:[0x418038060f77]LogFormatStringV@vmkernel#nover+0x1b3 stack: 0x100

2015-10-07T12:38:02.518Z cpu10:33172)0x4391a261ba20:[0x41803806171d]LogWarning@vmkernel#nover+0x55 stack: 0x2e32303a38333a32

2015-10-07T12:38:02.518Z cpu10:33172)0x4391a261bb50:[0x418038061cd8]_Warning@vmkernel#nover+0x50 stack: 0x4391a261bbb0

2015-10-07T12:38:02.518Z cpu10:33172)0x4391a261bbb0:[0x4180380f95e5]VmMemPf@vmkernel#nover+0x3d9 stack: 0x46a2e6ad237d4

2015-10-07T12:38:02.518Z cpu10:33172)0x4391a261bc40:[0x4180380f9ee5]VmMemPf_UserWorldPageFault@vmkernel#nover+0xf9 stack: 0x3ffc630f

2015-10-07T12:38:02.519Z cpu10:33172)0x4391a261bc90:[0x4180385d43be]UserMem_HandleMapFault@<None>#<None>+0x1042 stack: 0x439339927b00

2015-10-07T12:38:02.519Z cpu10:33172)0x4391a261bec0:[0x4180385ba002]User_Exception@<None>#<None>+0x126 stack: 0x431214197fc0

2015-10-07T12:38:02.519Z cpu10:33172)0x4391a261bf10:[0x4180380552c3]Int14_PF@vmkernel#nover+0x17f stack: 0x3ffc1f761f0

2015-10-07T12:38:02.520Z cpu10:33172)0x4391a261bf30:[0x4180380c7044]gate_entry_@vmkernel#nover+0x0 stack: 0x0 mentioning VmMemPf

Symptoms:
VMware ESXi 6.x host experiences a purple diagnostic screen

Environment

VMware vSphere ESXi 6.0

Cause

Attempts to launch VMs with higher display resolution or a multiple monitor setup might result in a flood of warning messages similar to the following in the vmkernel log file and might cause the host to crash due to excessive load of logging:

ESC[7m2015-10-07T12:38:02.459Z cpu5:498764)WARNING: VmMemPf: vm 498729: 654: COW copy failed: pgNum=0x23de9, mpn=0x3fffffffffESC[0m

Resolution

This issue is resolved in ESXi 6.0 U1b (P02)