From 2c696013cd8f68504c225526efa2f6c6c3ad265e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marek=20Marczykowski-G=C3=B3recki?=
 <marmarek@invisiblethingslab.com>
Date: Mon, 18 Feb 2019 23:59:54 +0100
Subject: [PATCH] Do not use /proc/xen for detecting dom0 anymore

Phase out /proc/xen usage. Relevant device files are available in
/dev/xen. Dom0 check can be replaced with uuid check - dom0 have
well-known value of all-0.

QubesOS/qubes-issues#2540
---
 initramfs-tools/qubes_vm | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/initramfs-tools/qubes_vm b/initramfs-tools/qubes_vm
index e12baf6..3a0b7d4 100755
--- a/initramfs-tools/qubes_vm
+++ b/initramfs-tools/qubes_vm
@@ -1,6 +1,6 @@
 #!/bin/sh
 
-if grep -q control_d /proc/xen/capabilities; then
+if grep -q '^[0-]*$' /sys/hypervisor/uuid; then
     echo "Not intended for dom0"
     exit 0
 fi