From cb3a0f55e8e37c4f7db239ce27491fd66c9503cc Mon Sep 17 00:00:00 2001
From: Michael Fellinger <michael.fellinger@iohk.io>
Date: Wed, 20 Oct 2021 22:09:16 +0200
Subject: [PATCH] stage2: use atomic bind mounts

---
 nixos/modules/system/boot/stage-2-init.sh | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/nixos/modules/system/boot/stage-2-init.sh b/nixos/modules/system/boot/stage-2-init.sh
index 50ee0b8841e5..afaca2e4158d 100644
--- a/nixos/modules/system/boot/stage-2-init.sh
+++ b/nixos/modules/system/boot/stage-2-init.sh
@@ -62,9 +62,11 @@ chown -f 0:30000 /nix/store
 chmod -f 1775 /nix/store
 if [ -n "@readOnlyStore@" ]; then
     if ! [[ "$(findmnt --noheadings --output OPTIONS /nix/store)" =~ ro(,|$) ]]; then
-        # FIXME when linux < 4.5 is EOL, switch to atomic bind mounts
-        #mount /nix/store /nix/store -o bind,remount,ro
-        mount --bind /nix/store /nix/store
+        if [ -z "$container" ]; then
+            mount --bind /nix/store /nix/store
+        else
+            mount --rbind /nix/store /nix/store
+        fi
         mount -o remount,ro,bind /nix/store
     fi
 fi