From 5bad652ff3fe25e855487438a05ca4b988b500f5 Mon Sep 17 00:00:00 2001
From: Alyssa Ross <hi@alyssa.is>
Date: Sat, 6 Jan 2024 12:24:15 +0100
Subject: [PATCH] linux: enable UDMABUF

> A driver to let userspace turn memfd regions into dma-bufs.
> Qemu can use this to create host dmabufs for guest framebuffers.

Enabled by Fedora and Arch.
---
 pkgs/os-specific/linux/kernel/common-config.nix | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/pkgs/os-specific/linux/kernel/common-config.nix b/pkgs/os-specific/linux/kernel/common-config.nix
index 746991c00b7e..da0659e4231f 100644
--- a/pkgs/os-specific/linux/kernel/common-config.nix
+++ b/pkgs/os-specific/linux/kernel/common-config.nix
@@ -672,6 +672,8 @@ let
 
       VFIO_PCI_VGA = mkIf stdenv.is64bit yes;
 
+      UDMABUF = whenAtLeast "4.20" yes;
+
       # VirtualBox guest drivers in the kernel conflict with the ones in the
       # official additions package and prevent the vboxsf module from loading,
       # so disable them for now.