1 files changed, 11 insertions, 4 deletions
diff --git a/nixos/modules/system/boot/loader/grub/install-grub.pl b/nixos/modules/system/boot/loader/grub/install-grub.pl
index 4fa157641a4a..06eece5025f8 100644
--- a/nixos/modules/system/boot/loader/grub/install-grub.pl
+++ b/nixos/modules/system/boot/loader/grub/install-grub.pl
@@ -12,8 +12,10 @@ require List::Compare;
 use POSIX;
 use Cwd;
 
+# system.build.toplevel path
 my $defaultConfig = $ARGV[1] or die;
 
+# Grub config XML generated by grubConfig function in grub.nix
 my $dom = XML::LibXML->load_xml(location => $ARGV[0]);
 
 sub get { my ($name) = @_; return $dom->findvalue("/expr/attrs/attr[\@name = '$name']/*/\@value"); }
@@ -97,6 +99,8 @@ sub PathInMount {
     }
     return 1;
 }
+
+# Figure out what filesystem is used for the directory with init/initrd/kernel files
 sub GetFs {
     my ($dir) = @_;
     my $bestFs = Fs->new(device => "", type => "", mount => "");
@@ -136,7 +140,10 @@ my $driveid = 1;
 sub GrubFs {
     my ($dir) = @_;
     my $fs = GetFs($dir);
-    my $path = "/" . substr($dir, length($fs->mount));
+    my $path = substr($dir, length($fs->mount));
+    if (substr($path, 0, 1) ne "/") {
+      $path = "/$path";
+    }
     my $search = "";
 
     if ($grubVersion > 1) {
@@ -169,7 +176,7 @@ sub GrubFs {
                 $search = $types{$fsIdentifier} . ' ';
 
                 # Based on the type pull in the identifier from the system
-                my ($status, @devInfo) = runCommand("blkid -o export @{[$fs->device]}");
+                my ($status, @devInfo) = runCommand("@utillinux@/bin/blkid -o export @{[$fs->device]}");
                 if ($status != 0) {
                     die "Failed to get blkid info for @{[$fs->mount]} on @{[$fs->device]}";
                 }
@@ -182,7 +189,7 @@ sub GrubFs {
 
             # BTRFS is a special case in that we need to fix the referrenced path based on subvolumes
             if ($fs->type eq 'btrfs') {
-                my ($status, @id_info) = runCommand("btrfs subvol show @{[$fs->mount]}");
+                my ($status, @id_info) = runCommand("@btrfsprogs@/bin/btrfs subvol show @{[$fs->mount]}");
                 if ($status != 0) {
                     die "Failed to retrieve subvolume info for @{[$fs->mount]}\n";
                 }
@@ -190,7 +197,7 @@ sub GrubFs {
                 if ($#ids > 0) {
                     die "Btrfs subvol name for @{[$fs->device]} listed multiple times in mount\n"
                 } elsif ($#ids == 0) {
-                    my ($status, @path_info) = runCommand("btrfs subvol list @{[$fs->mount]}");
+                    my ($status, @path_info) = runCommand("@btrfsprogs@/bin/btrfs subvol list @{[$fs->mount]}");
                     if ($status != 0) {
                         die "Failed to find @{[$fs->mount]} subvolume id from btrfs\n";
                     }