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I am trying to create GPU passthrough from ubuntu host to windows guest. I want to know if I could enable GPU passthrough on my laptop. I tried searching for boot options on link but all iommu options are related to AMD system. My system configurations are:

CPU: i7 5000U
GPU: Nvidia 920M
Motherboard: Dell (Dell laptop Inspiron 5588)

the output of dmesg | grep -i dmar

[    0.011173] ACPI: DMAR 0x00000000CB3AA790 0000B0 (v01 INTEL  BDW      00000001 INTL 00000001)
[    0.118907] DMAR: Host address width 39
[    0.118909] DMAR: DRHD base: 0x000000fed90000 flags: 0x0
[    0.118915] DMAR: dmar0: reg_base_addr fed90000 ver 1:0 cap 1c0000c40660462 ecap 7e1ff0505e
[    0.118917] DMAR: DRHD base: 0x000000fed91000 flags: 0x1
[    0.118920] DMAR: dmar1: reg_base_addr fed91000 ver 1:0 cap d2008c20660462 ecap f010da
[    0.118923] DMAR: RMRR base: 0x000000cbef4000 end: 0x000000cbf02fff
[    0.118924] DMAR: RMRR base: 0x000000cd000000 end: 0x000000cf7fffff
[    0.118927] DMAR-IR: IOAPIC id 2 under DRHD base  0xfed91000 IOMMU 1
[    0.118929] DMAR-IR: HPET id 0 under DRHD base 0xfed91000
[    0.118930] DMAR-IR: x2apic is disabled because BIOS sets x2apic opt out bit.
[    0.118931] DMAR-IR: Use 'intremap=no_x2apic_optout' to override the BIOS setting.
[    0.119374] DMAR-IR: Enabled IRQ remapping in xapic mode
[    0.229772] pci 0000:00:02.0: DMAR: Disabling IOMMU for graphics on this chipset

And the output of lspci | grep -i nvidia

08:00.0 3D controller: NVIDIA Corporation GK208BM [GeForce 920M] (rev a1)
08:00.1 Audio device: NVIDIA Corporation GK208 HDMI/DP Audio Controller (rev a1)

The output of lspci -nn -s 00:02.0 -v | head -2

00:02.0 VGA compatible controller [0300]: Intel Corporation HD Graphics 5500 [8086:1616] (rev 09) (prog-if 00 [VGA controller])
    DeviceName:  Onboard IGD

I made sure I enable direct IO in the virtualization section of BIOS.

All the answers I saw on the internet were either too old or not for my chipset thus making it difficult for someone like me who is new to Linux, difficult to understand. It will be great if someone can tell me how I should proceed? Does my GPU supports passthrough? If any additional information is required then please let me know.

Thank you.

Mandar Sadye
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    The message `pci 0000:00:02.0: DMAR: Disabling IOMMU for graphics on this chipset`suggests there might be some hardware bug or other compatibility issue that prevents using IOMMU with the GPU. It would be helpful to know the chipset used in your system: what is the output of `lspci -nn -s 00:02.0 -v | head -2`? – telcoM Dec 25 '20 at 13:25
  • @telcoM thanks for the reply. I added the output of command. – Mandar Sadye Dec 25 '20 at 16:05
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    Oh, that looks like your laptop has dual GPUs: an Inte HD Graphics 5500 integrated to the main CPU, and also a discrete Nvidia GPU. And the iGPU model indicates your chipset is a mid-range Broadwell chipset. The important question is now, does your Nvidia GPU have access to any displays, or is it intended only as RAM-based 3d booster to supplement the Intel iGPU? Unfortunately this information can be hard to find out. Does `/sys/kernel/debug/vgaswitcheroo/switch` exist on your system? If you `cat` it as root, what does it say? – telcoM Dec 25 '20 at 17:15
  • @telcoM Sorry but there is no folder "vgaswitcheroo" in "/sys/kernel/debug" – Mandar Sadye Dec 26 '20 at 07:52

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