On Windows RS builds 14361 and higher hyper-v and vbox don't work due to hyperguard

[Trance]

Hyperguard (starting with TH2) blocks programs from scribbling over control registers like CR4. In RS1, Hyper-V opportunistically enables secure kernel which brings in Hyperguard when the Hyper-V role is enabled.

VBox needs to do something here, detect an incompatible hypervisor and not bugcheck

HyperGuard intercepts the write to CR4 and injects a #GP (here is the value VirtualBox tried to write: rax=0000000000000274). VirtualBox does not require VT-x to run 32-bit guests. In RS1, HyperGuard / secure kernel is always present when the hypervisor is present. That means that if a customer installs Hyper-V and VirtualBox, the machine will always bugcheck when the first VirtualBox VM is started. This was not the case in TH2.

STACK_TEXT:  
ffffde00`9e2ac668 ffffde00`99dca712 : 00000000`00000010 fffff802`1eec16c6 00000000`00000000 ffff858f`1cfea1a0 : 0xffffde00`99dca890
ffffde00`9e2ac670 00000000`00000010 : fffff802`1eec16c6 00000000`00000000 ffff858f`1cfea1a0 00000000`0000639f : 0xffffde00`99dca712
ffffde00`9e2ac678 fffff802`1eec16c6 : 00000000`00000000 ffff858f`1cfea1a0 00000000`0000639f fffff802`1ef2aff0 : 0x10
ffffde00`9e2ac680 fffff802`1eec2ae8 : 00000000`c8077200 ffffde00`9e2acb80 00000000`0022821c ffff858f`20a02680 : VMMR0!VMMR0EntryFast+0xf96
ffffde00`9e2ac6e0 fffff802`1cb66250 : 00000000`00000000 fffff800`81896aa9 fffff6bf`fe4b27b8 ffff858f`1faedd00 : VMMR0!VMMR0EntryEx+0xe8
ffffde00`9e2ac750 fffff802`1cb74140 : ffff858f`00000000 00000000`00000030 00000000`00000030 00000000`00000000 : VBoxDrv!SUPR0PageFree+0x1e30
ffffde00`9e2ac7b0 fffff800`818c07de : fffff802`1cb73e70 00000000`0022821c 00000000`0531f9c8 ffffde00`00000030 : VBoxDrv!SUPR0SuspendVTxOnCpu+0x29f0
ffffde00`9e2ac850 fffff800`818bf9c6 : ffff858f`1faedd00 00000000`00000000 00000000`00000000 00000000`00000000 : nt!IopXxxControlFile+0x51e [d:\rs1\minkernel\ntos\io\iomgr\internal.c @ 10464]
ffffde00`9e2aca20 fffff800`815e1193 : fffff6fb`7dafff90 fffff6fb`7dbed7f8 ffffc7cb`c9738199 00000000`00000000 : nt!NtDeviceIoControlFile+0x56 [d:\rs1\minkernel\ntos\io\iomgr\devctrl.c @ 110]
ffffde00`9e2aca90 00007ffc`b7dc1344 : 00000000`00000000 00000000`00000000 00000000`00000000 00000000`00000000 : nt!KiSystemServiceCopyEnd+0x13 [d:\rs1\minkernel\ntos\ke\amd64\trap.asm @ 2564]
00000000`0531f928 00000000`00000000 : 00000000`00000000 00000000`00000000 00000000`00000000 00000000`00000000 : 0x00007ffc`b7dc1344

[Frank Mehnert]

Still relevant with VBox 5.1.20?

[ReMarkble]

Windows 10 Enterprise still has this issue.

Tested with VBox 5.1.22.

Disabling Device Guard and Credential Guard in the bios and windows boot parameters and the registry are a place to start.

[aeichner]

VirtualBox supports Hyper-V as its virtualization backend, closing. Please create new tickets or use other existing ones for issues related to that.