Status: Resolved.
130624: Turns out this issue was caused by a storage problem.
130211: This issue is triggered when a machine is handling a surprise removal for a Csv volume. Nothing conclusive yet, but I wanted to see if there is anyone out there with the same issue. The 0x9F code indicates that a driver has failed to complete a power IRP within a specific time (usually 10 minutes).
The failure bucket is:
0x9F_4_IMAGE_CsvFs.sys
When you have a dump with this bucket, start with running !pnptriage. The stack of the relevant device event thread will show:
00 fffff880`0853a160 fffff801`76ea73fc nt!KiSwapContext+0x76
01 fffff880`0853a2a0 fffff801`76ea520f nt!KiCommitThreadWait+0x23c
02 fffff880`0853a360 fffff801`76eeeead nt!KeWaitForSingleObject+0x1cf
03 fffff880`0853a3f0 fffff801`76ebca61 nt!ExpWaitForResource+0xbd
04 fffff880`0853a480 fffff880`081320a2 nt!ExAcquireResourceExclusiveLite+0x1e1
05 fffff880`0853a4f0 fffff880`0813066f CsvFs!CsvFsAcquireExclusiveVcb_Real+0x3a
06 fffff880`0853a520 fffff880`08130369 CsvFs!CsvFsPnpSurpriseRemove+0x3b
07 fffff880`0853a580 fffff880`081301ba CsvFs!CsvFsCommonPnp+0x105
08 fffff880`0853a5c0 fffff880`00b024ee CsvFs!CsvFsFsdPnp+0xea
09 fffff880`0853a650 fffff880`00b000b6 fltmgr!FltpLegacyProcessingAfterPreCallbacksCompleted+0x25e
0a fffff880`0853a6f0 fffff801`77186e07 fltmgr!FltpDispatch+0xb6
0b fffff880`0853a750 fffff801`772976ec nt!IopSynchronousCall+0xc7
0c fffff880`0853a7c0 fffff801`77298ba5 nt!IopRemoveDevice+0x100
0d fffff880`0853a880 fffff801`772974f5 nt!PnpSurpriseRemoveLockedDeviceNode+0x15d
0e fffff880`0853a8d0 fffff801`772973e5 nt!PnpDeleteLockedDeviceNode+0x59
0f fffff880`0853a910 fffff801`772956c7 nt!PnpDeleteLockedDeviceNodes+0xa1
10 fffff880`0853a970 fffff801`77289ab1 nt!PnpProcessQueryRemoveAndEject+0x647
11 fffff880`0853aae0 fffff801`771831fd nt!PnpProcessTargetDeviceEvent+0xa1
12 fffff880`0853ab20 fffff801`76eb7511 nt!PnpDeviceEventWorker+0x2e5
13 fffff880`0853ab80 fffff801`76e26551 nt!ExpWorkerThread+0x142
14 fffff880`0853ac10 fffff801`76e64dd6 nt!PspSystemThreadStartup+0x59
15 fffff880`0853ac60 00000000`00000000 nt!KiStartSystemThread+0x16
Did your machine crash with the same STOP code and stack? Then please let me know!