"nvrm: this pci i/o region assigned to your nvidia device is invalid: nvrm: bar2 is 0M @ #x# (PCI : ####:##:##.#)" error appears during the guest OS bootup

Products

• VMware vSphere ESXi

Issue/Introduction

• In Linux Virtual Machines configured for PCI passthrough, the guest OS reports the error "nvrm: this pci i/o region assigned to your nvidia device is invalid: nvrm: bar2 is 0M @ #x# (PCI : ####:##:##.#)" indicating that the base address register 2 (BAR2) is reporting a zero size and zero address. 
• The impacted virtual machine is configured to use BIOS boot mode. 

Environment

VMware vSphere ESXi 8.x

Cause

• The issue occurs due to the legacy BIOS boot mode in the Virtual Machine being unable to map the 64-bit Memory-Mapped I/O (MMIO) address space required by the NVIDIA GPU.

Resolution

• Log in to the vSphere Client using the local SSO account or an account with the administrator privilege. 
• Power off the virtual machine. 
• Navigate to "Edit Settings > VM Options > Boot Options > select EFI" to configure the UEFI for the virtual machine.
  • Note: The Virtual Machine must be reconfigured to use UEFI (Unified Extensible Firmware Interface) or EFI firmware instead of BIOS. 
• Power on the virtual machine. 

Additional Information

Using GPUs with Virtual Machines on vSphere – Part 2: VMDirectPath I/O