ESXi 6.0 host fails with a purple diagnostic screen reporting the FTCptWriterFunc function call

Products

• VMware vSphere ESXi

Issue/Introduction

Symptoms:

• The ESXi host fails with the purple diagnostic screen.
  
  
• In the purple diagnostic screen, you see backtrace similar to:

ESXi 6.0.0 build-2715440 PSOD:2015-07-31T20:13:09.387Z cpu5:33264)@BlueScreen: PCPU 13: no heartbeat (2/2 IPIs received)
2015-07-31T20:13:09.387Z cpu5:33264)Code start: 0x418000e00000 VMK uptime: 11:06:37:47.154
2015-07-31T20:13:09.387Z cpu5:33264)Saved backtrace from: pcpu 13 Heartbeat NMI
2015-07-31T20:13:09.387Z cpu5:33264)0x4390f671bec0:[0x418001f4f630]FTCptWriterFunc@<None>#<None>+0x414 stack: 0x410021800000
2015-07-31T20:13:09.388Z cpu5:33264)0x4390f671bfd0:[0x41800101231e]CpuSched_StartWorld@vmkernel#nover+0xa2 stack: 0x0
2015-07-31T20:13:09.390Z cpu5:33264)base fs=0x0 gs=0x418041400000 Kgs=0x0
2015-07-31T20:13:09.332Z cpu13:624334)NMI: 681: NMI IPI recvd. We Halt.eip(base):ebp:cs[0x114f630(0x418000e00000):0x4306504afc38:0x4010](Src0x1,CPU13)
2015-07-31T20:12:56.332Z cpu13:624334)NMI: 709: NMI IPI received. Was eip(base):ebp:cs [0x114f630(0x418000e00000):0x4306504afc38:0x4010](Src 0x1, CPU13)
2015-07-31T20:13:09.332Z cpu13:624334)NMI: 681: NMI IPI recvd. We Halt. eip(base):ebp:cs [0x114f630(0x418000e00000):0x4306504afc38:0x4010](Src0x1, CPU13)
2015-07-31T20:12:56.332Z cpu13:624334)NMI: 709: NMI IPI received. Was eip(base):ebp:cs [0x114f630(0x418000e00000):0x4306504afc38:0x4010](Src 0x1, CPU13)
2015-07-31T20:13:09.393Z cpu5:33264)Backtrace for current CPU #5, worldID=33264, rbp=0x0
2015-07-31T20:13:09.393Z cpu5:33264)0x4390cf81b960:[0x418000e76eea]PanicvPanicInt@vmkernel#nover+0x37e stack: 0x4390cf81b9f8, 0x43004d0
2015-07-31T20:13:09.393Z cpu5:33264)0x4390cf81b9f0:[0x418000e7725e]Panic_WithBacktrace@vmkernel#nover+0x56 stack: 0x4390cf81ba60, 0x439
2015-07-31T20:13:09.393Z cpu5:33264)0x4390cf81ba60:[0x41800113c7eb]Heartbeat_DetectCPULockups@vmkernel#nover+0x4f7 stack: 0x3c1081ea8,
2015-07-31T20:13:09.393Z cpu5:33264)0x4390cf81bad0:[0x418000e881b6]Timer_BHHandler@vmkernel#nover+0xea stack: 0x43908208ab38, 0x0, 0x8f
2015-07-31T20:13:09.393Z cpu5:33264)0x4390cf81bb60:[0x418000e32254]BH_DrainAndDisableInterrupts@vmkernel#nover+0x78 stack: 0x1000000ef,
2015-07-31T20:13:09.393Z cpu5:33264)0x4390cf81bbf0:[0x418000e55fa2]IDT_IntrHandler@vmkernel#nover+0x1ce stack: 0x0, 0x418041400200, 0x0
2015-07-31T20:13:09.393Z cpu5:33264)0x4390cf81bc20:[0x418000ec6044]gate_entry_@vmkernel#nover+0x0 stack: 0x0, 0x0, 0x0, 0x0, 0x41804140
2015-07-31T20:13:09.393Z cpu5:33264)0x4390cf81bce0:[0x4180010fddac]Power_HaltPCPU@vmkernel#nover+0x1e8 stack: 0x417fc1081ea0, 0x4180415
2015-07-31T20:13:09.393Z cpu5:33264)0x4390cf81bd30:[0x41800100d5b2]CpuSchedIdleLoopInt@vmkernel#nover+0x3f2 stack: 0x8ffd5f26c9ae9, 0x1
2015-07-31T20:13:09.393Z cpu5:33264)0x4390cf81bdb0:[0x418001010af2]CpuSchedDispatch@vmkernel#nover+0x1576 stack: 0x0, 0x439d91bdbc80, 0
2015-07-31T20:13:09.393Z cpu5:33264)0x4390cf81bee0:[0x418001011710]CpuSchedWait@vmkernel#nover+0x240 stack: 0x0, 0x430053ede240, 0x550
2015-07-31T20:13:09.393Z cpu5:33264)0x4390cf81bf60:[0x418000fd7afc]NetPollWorldCallback@vmkernel#nover+0x54 stack: 0x100e, 0x418001524c
2015-07-31T20:13:09.393Z cpu5:33264)0x4390cf81bfd0:[0x41800101231e]CpuSched_StartWorld@vmkernel#nover+0xa2 stack: 0x0, 0x0, 0x0, 0x0, 0

Note: The preceding log excerpts are only examples. Date, time, and environmental variables may vary depending on your environment.

Environment

VMware vSphere ESXi 6.0

Cause

This issue occurs if FT-protected virtual machines running on the host use an SVGA frame buffer size that is not a multiple of 128KB.

Resolution

To resolve this issue, set the SVGA frame buffer size on an FT-protected virtual machine to a multiple of 128KB.

To set the SVGA frame buffer size on an FT-protected virtual machine to a multiple of 128KB:

1. Open the .vmx file of the FT-protected virtual machine using a text editor.
   
   

2. Locate for this entry:
   
   svga.vramSize:= "SVGA_frame_buffer_size"

3. Set the SVGA frame buffer size on an FT-protected virtual machine to a multiple of 128KB:

   svga.vramSize = "Multiple_of_128KB"
   
   For example:

   svga.vramSize = "9306112"