It’s kind of a weird problem.
I have a driver that works reliably on basic disk systems. But enabling dynamic disks causes a 9F (basically a hang) on shutdown.
After some investigation, I’ve determined that dynamic disk changes the behaviour of the disk shutdown, serializing them or running them synchronously whereas the old behaviour was to simultaneously send IRP_MJ_POWER to all disks. Since my driver deliberately postpones shutdown until the boot disk gets the IRP, and they refuse to send me the boot disk IRP until one or more other disks are successfully shut down, I have a problem.
Now, maybe I shouldn’t be messing with the ordering, but so are they! Oh well. Maybe I’ll just explicitly not support Dynamic Disks or software RAID.
I can’t do that, unfortunately, because even after deleting the mirrors, returning all disks to basic disk, the same shutdown sequence persists. I’ve reproduced this across multiple instances.
Does anyone know how I can disable this behaviour? Or work around it?