[openwrt/openwrt] x86: grub2: search for the "kernel" filesystem on all disks

[LEDE Commits]

chunkeey pushed a commit to openwrt/openwrt.git, branch master:
https://git.openwrt.org/1050e66c8f7c67ab8b3d1895e2559f03baeb2345

commit 1050e66c8f7c67ab8b3d1895e2559f03baeb2345
Author: Jax Jiang <jax.jiang.007 at gmail.com>
AuthorDate: Fri Feb 11 01:46:55 2022 +0800

    x86: grub2: search for the "kernel" filesystem on all disks
    
    Previously, grub2 was hardcoded to always look on "hd0" for the
    kernel.
    
    This works well when the system only had a single disk.
    But if there was a second disk/stick present, it may have look
    on the wrong drive because of enumeration races.
    
    This patch utilizes grub2 search function to look for a filesystem
    with the label "kernel". This works thanks to existing setup in
    scripts/gen_image_generic.sh. Which sets the "kernel" label on
    both the fat and ext4 filesystem variants.
    
    Signed-off-by: Jax Jiang <jax.jiang.007 at gmail.com>
    Suggested-by: Alberto Bursi <bobafetthotmail at gmail.com> (MX100 WA)
    (word wrapped, slightly rewritten commit message, removed MX100 WA)
    Signed-off-by: Christian Lamparter <chunkeey at gmail.com>
---
 package/boot/grub2/Makefile                         |  8 ++++----
 target/linux/x86/base-files/lib/upgrade/platform.sh | 10 ----------
 target/linux/x86/image/grub-efi.cfg                 |  2 +-
 3 files changed, 5 insertions(+), 15 deletions(-)

diff --git a/package/boot/grub2/Makefile b/package/boot/grub2/Makefile
index 9c67ff589b..67b36842ec 100644
--- a/package/boot/grub2/Makefile
+++ b/package/boot/grub2/Makefile
@@ -120,28 +120,28 @@ define Package/grub2/install
 		-O i386-pc \
 		-c $(PKG_BUILD_DIR)/grub-early.cfg \
 		-o $(STAGING_DIR_IMAGE)/grub2/gpt-core.img \
-		at_keyboard biosdisk boot chain configfile fat linux ls part_gpt reboot serial vga
+		at_keyboard biosdisk boot chain configfile fat linux ls part_gpt reboot search serial vga
 	$(STAGING_DIR_HOST)/bin/grub-mkimage \
 		-d $(PKG_BUILD_DIR)/grub-core \
 		-p /boot/grub \
 		-O i386-pc \
 		-c ./files/grub-early.cfg \
 		-o $(STAGING_DIR_IMAGE)/grub2/generic-core.img \
-		at_keyboard biosdisk boot chain configfile ext2 linux ls part_msdos reboot serial vga
+		at_keyboard biosdisk boot chain configfile ext2 linux ls part_msdos reboot search serial vga
 	$(STAGING_DIR_HOST)/bin/grub-mkimage \
 		-d $(PKG_BUILD_DIR)/grub-core \
 		-p /boot/grub \
 		-O i386-pc \
 		-c ./files/grub-early.cfg \
 		-o $(STAGING_DIR_IMAGE)/grub2/eltorito.img \
-		at_keyboard biosdisk boot chain configfile iso9660 linux ls part_msdos reboot serial test vga
+		at_keyboard biosdisk boot chain configfile iso9660 linux ls part_msdos reboot search serial test vga
 	$(STAGING_DIR_HOST)/bin/grub-mkimage \
 		-d $(PKG_BUILD_DIR)/grub-core \
 		-p /boot/grub \
 		-O i386-pc \
 		-c ./files/grub-early.cfg \
 		-o $(STAGING_DIR_IMAGE)/grub2/legacy-core.img \
-		biosdisk boot chain configfile ext2 linux ls part_msdos reboot serial vga
+		biosdisk boot chain configfile ext2 linux ls part_msdos reboot search serial vga
 endef
 
 define Package/grub2-efi/install
diff --git a/target/linux/x86/base-files/lib/upgrade/platform.sh b/target/linux/x86/base-files/lib/upgrade/platform.sh
index 94bf80b144..d8f2eba97e 100644
--- a/target/linux/x86/base-files/lib/upgrade/platform.sh
+++ b/target/linux/x86/base-files/lib/upgrade/platform.sh
@@ -65,16 +65,6 @@ platform_do_bootloader_upgrade() {
 			"/dev/$diskdev" \
 		&& touch /tmp/boot/boot/grub/upgraded
 
-        case "$(board_name)" in
-        cisco-mx100-hw)
-            # If the MX100 is booted UEFI AND the SATA HDD exists, we need to change
-            # grub's root= to hd1 for it to boot correctly, otherwise we can keep it hd0.
-            if [ -d /sys/firmware/efi ] && [ "$(ls -a /dev/sd[a-z] | wc -w)" -gt 1 ] ; then
-                sed -i "s|hd0,${parttable}1|hd1,${parttable}1|g" /tmp/boot/boot/grub/grub.cfg
-            fi
-            ;;
-        esac
-
 		umount /tmp/boot
 	fi
 }
diff --git a/target/linux/x86/image/grub-efi.cfg b/target/linux/x86/image/grub-efi.cfg
index 14d30e88e4..bbb31f7747 100644
--- a/target/linux/x86/image/grub-efi.cfg
+++ b/target/linux/x86/image/grub-efi.cfg
@@ -3,7 +3,7 @@
 
 set default="0"
 set timeout="@TIMEOUT@"
-set root='(hd0,gpt1)'
+search -l kernel -s root
 
 menuentry "@TITLE@" {
 	linux /boot/vmlinuz @GPT_ROOTPART@ @CMDLINE@ noinitrd