3 Replies Latest reply on Jun 21, 2018 10:16 AM by mgbaskar

    AMD uProf: Bluescreen when combining IBS with stack sampling

    ext3h

      Currently running Windows 18.03 on a Threadripper 1920X based platform.

       

      The combination of IBS with "kernel and user mode" stack samplingin any GUI application reliably results in a bluescreen after a few seconds for me:

       

      DRIVER IRQL NOT LESS OR EQUAL in AMDCpuProfiler.sys

       

      (This problem isn't actually unique to uProf. Older versions of VTune had the very same problem, that performance counters would trigger stack traces at illegal times, resulting in the very same bluescreen.)

        • Re: AMD uProf: Bluescreen when combining IBS with stack sampling
          mgbaskar

          Hi,

          We will work on this issue to get it fixed. In the meantime,

          1. Can you please provide the output "AMDuProfCLI.exe info --system"
          2. If the callstack sampling is disabled, do you observe this issue?
            • Re: AMD uProf: Bluescreen when combining IBS with stack sampling
              ext3h
              CPU Info:
                      AMD Cpu: Yes
                      Family: 0x17
                      Model: 0x1
                      Stepping: 0x1
                      Local APIC: True
                      SMT Enabled: True
                      Die Count (per socket): 2
                      Thread Count (per socket): 24
                      Thread Count (per CCX): 6
                      Thread Count (per core): 2
              
              PERF Features:
                      Core PMC Available: True
                      L3 PMC Available: True
                      DF PMC Available: True
                      PERF TS Available: False
              
              IBS Features:
                      IBS Available: True
                      Ibs FetchCtlExtd Available: True
                      Ibs ExtCount Available: True
                      Ibs Dispatch Available: True
                      Ibs BrTgtAddr Available: True
                      Ibs OpData4 Available: False
              
              RAPL, CEF Features:
                      RAPL Available: True
                      APERF & MPERF Available: True
                      Read Only APERF & MPERF Available: True
                      IRPERF Available: True
                      HW P-State Control Available: True
              
              Hypervisor Features:
                      Hypervisor: False
              

               

              The bluescreens do not occur with sampling turned off, or sampling limited to user mode. (At least I couldn't reproduce them at all with sampling turned of entirely. Haven't tested user mode only sampling extensively.)