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Unloading drivers for filesystems

Jorgen_LundmanJorgen_Lundman Member - All Emails Posts: 47

So when I started working on my FSD, I used devstudio to deploy the driver to the remove VM, then deploy it again for it to unload my driver and I could test the unloading routines, stepping through the code etc.

But recently I have noticed I can no longer unload, using either devstudio, or devcon.exe to uninstall will just result in a timeout period, followed by reboot.

So I went back to MS site and grabbed helloworld driver, only to find it also does not unload.

Did something change with devstudio or drivers that I missed? What am I doing wrong here.

My INF file - which I think might have something to do with it all - is here: (and probably wrong)


  • rod_widdowsonrod_widdowson Member - All Emails Posts: 1,151

    Being a dinosaur I don't use this whole devstudio deploy thing (I use kdfiles) But I'll note that by the time a FSD gets any sort of shape it is pretty much unloadable because stuff pinned in the cache requires that your driver stay around. I normally rely of VMWare snapshots and DEMAND start (plus, as I say kdfiles) to redeploy.

  • Jorgen_LundmanJorgen_Lundman Member - All Emails Posts: 47

    Ok so to update, we wrote a small installer.exe that when asked to uninstall will send a made up IOCTL to the kernel, which then calls zfs_ioc_unregister_fs();, this then allows us to unload the driver with DefaultUninstall.

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