Crash Dump Analysis Patterns (Part 42k)

Here we provide examples of threads waiting for pushlocks as they are not normally seen in crash dumps:

THREAD fffffa80033b5b50  Cid 0004.0030  Teb: 0000000000000000 Win32Thread: 0000000000000000 WAIT: (WrPushLock) KernelMode Non-Alertable
fffff880021d9750  SynchronizationEvent
Not impersonating
DeviceMap                 fffff8a0000088f0
Owning Process            fffffa80033879e0       Image:         System
Attached Process          fffffa800439c620       Image:         AppA.exe
Wait Start TickCount      30819          Ticks: 14746574 (2:15:54:08.028)
Context Switch Count      2800
UserTime                  00:00:00.000
KernelTime                00:00:00.374
Win32 Start Address nt!ExpWorkerThread (0xfffff8000189e530)
Stack Init fffff880021d9db0 Current fffff880021d9470
Base fffff880021da000 Limit fffff880021d4000 Call 0
Priority 12 BasePriority 12 UnusualBoost 0 ForegroundBoost 0 IoPriority 2 PagePriority 5
Child-SP          RetAddr           Call Site
fffff880`021d94b0 fffff800`0188aa32 nt!KiSwapContext+0×7a
fffff880`021d95f0 fffff800`0189bd8f nt!KiCommitThreadWait+0×1d2
fffff880`021d9680 fffff800`018c4bf8 nt!KeWaitForSingleObject+0×19f
fffff880`021d9720 fffff800`01c2915d nt!ExfAcquirePushLockShared+0×138
fffff880`021d97a0 fffff800`01c6da31 nt!MmEnumerateAndReferenceImages+0×6d
[…]
fffff880`021d9cb0 fffff800`01b2be5a nt!ExpWorkerThread+0×111
fffff880`021d9d40 fffff800`01885d26 nt!PspSystemThreadStartup+0×5a
fffff880`021d9d80 00000000`00000000 nt!KxStartSystemThread+0×16

THREAD fffffa8003c9d600  Cid 0004.00ac  Teb: 0000000000000000 Win32Thread: 0000000000000000 WAIT: (WrPushLock) KernelMode Non-Alertable
fffff880023d1b30  SynchronizationEvent
Not impersonating
DeviceMap                 fffff8a0000088f0
Owning Process            fffffa80033879e0       Image:         System
Attached Process          N/A            Image:         N/A
Wait Start TickCount      177686         Ticks: 14599707 (2:15:15:56.888)
Context Switch Count      1590
UserTime                  00:00:00.000
KernelTime                00:00:00.124
Win32 Start Address 0xfffff80001bac754
Stack Init fffff880023d1db0 Current fffff880023d1850
Base fffff880023d2000 Limit fffff880023cc000 Call 0
Priority 15 BasePriority 15 UnusualBoost 0 ForegroundBoost 0 IoPriority 2 PagePriority 5
Child-SP          RetAddr           Call Site
fffff880`023d1890 fffff800`0188aa32 nt!KiSwapContext+0×7a
fffff880`023d19d0 fffff800`0189bd8f nt!KiCommitThreadWait+0×1d2
fffff880`023d1a60 fffff800`01886183 nt!KeWaitForSingleObject+0×19f
fffff880`023d1b00 fffff800`01cd9982 nt!ExfAcquirePushLockExclusive+0×188
[…]
fffff880`023d1d40 fffff800`01885d26 nt!PspSystemThreadStartup+0×5a
fffff880`023d1d80 00000000`00000000 nt!KxStartSystemThread+0×16

Instead of explaining what a pushlock is we provide a link to ntdebugging blog article.

- Dmitry Vostokov @ DumpAnalysis.org + TraceAnalysis.org -

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