Backport the UUID grub fix to bullseye too

tools/boot/bullseye/boot-arm64

@@ -91,6 +91,8 @@ if [ -d boot$N/grub ] ; then
     mv boot$N/grub/* $CDDIR/boot/grub/
     rmdir boot$N/grub
 
+    change_grub_cfg_uuid $CDDIR
+
     # Stuff the EFI boot files into a FAT filesystem, making it as
     # small as possible. We end up re-packing like this in case we're
     # making a multi-arch image

tools/boot/bullseye/boot-armhf

@@ -90,6 +90,8 @@ if [ -d boot$N/grub ] ; then
     mv boot$N/grub/* $CDDIR/boot/grub/
     rmdir boot$N/grub
 
+    change_grub_cfg_uuid $CDDIR
+
     # Stuff the EFI boot files into a FAT filesystem, making it as
     # small as possible. We end up re-packing like this in case we're
     # making a multi-arch image

tools/boot/bullseye/boot-hurd-common

@@ -134,6 +134,8 @@ if [ $BOOT_EFI -ne 0 ] ; then
     mv boot$N/grub/* $CDDIR/boot/grub/
     rmdir boot$N/grub
 
+    change_grub_cfg_uuid $CDDIR
+
     # Stuff the EFI boot files into a FAT filesystem, making it as
     # small as possible. We end up re-packing like this in case we're
     # making a multi-arch image

tools/boot/bullseye/boot-ia64

@@ -91,6 +91,8 @@ if [ -d boot$N/grub ] ; then
     # small as possible. We end up re-packing like this in case we're
     # making a multi-arch image
 
+    change_grub_cfg_uuid $CDDIR
+
     # First, work out how many blocks we need
     blocks=$(calculate_efi_image_size $CDDIR)
 

tools/boot/bullseye/boot-x86

@@ -453,6 +453,8 @@ if [ -d boot$N/isolinux/grub ] && [ $BOOT_EFI -ne 0 ] ; then
     # small as possible. We end up re-packing like this in case we're
     # making a multi-arch image
 
+    change_grub_cfg_uuid $CDDIR
+
     # First, work out how many blocks we need
     blocks=$(calculate_efi_image_size $CDDIR)
 

tools/boot/bullseye/common.sh

@@ -222,3 +222,17 @@ extra_image () {
         fi
     done
 }
+
+change_grub_cfg_uuid () {
+    CDDIR=$1
+
+    # We (used to) look for /.disk/info in grub.cfg to find this
+    # Debian media once we've booted via EFI. This is not 100%
+    # reliable - see #1024346 and #1024720 for examples where this
+    # fails. Instead, let's generate a UUID here and use that as a
+    # flag file.
+    UUID=$(uuidgen)
+    mkdir -p $CDDIR/.disk/id
+    touch $CDDIR/.disk/id/$UUID
+    sed -i "/search --file --set=root/s,.disk/info,.disk/id/$UUID," $CDDIR/EFI/debian/grub.cfg
+}