Only set blsdir if /boot/loader/entries is in a btrfs or zfs partition

Commit bfc756f8d86 ("Set blsdir if the BLS directory path isn't one of the
looked up by default") attempted to set blsdir if /boot/loader/entries was
not the real path of the directory containing the BLS snippets. Which may
be the case if for example /boot/loader/entries is in a btrfs subvolume.

But in the case of ostree, /boot/loader is a symlink to the directory with
the entries for the current deployment. So with ostree the blsdir will be
wrongly set, since GRUB is able to follow the symlinks just fine. In fact,
it has to follow the symlink since otherwise GRUB will always use the BLS
files for the deployment that the symlink pointed out when blsdir was set.

So only set blsdir if /boot/loader/entries is in a btrfs or zfs partition.

Related: rhbz#1688453

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>

0286-Only-set-blsdir-if-boot-loader-entries-is-in-a-btrfs.patch

@@ -0,0 +1,55 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Javier Martinez Canillas <javierm@redhat.com>
+Date: Tue, 19 Mar 2019 01:27:57 +0100
+Subject: [PATCH] Only set blsdir if /boot/loader/entries is in a btrfs or zfs
+ partition
+
+Commit bfc756f8d86 ("Set blsdir if the BLS directory path isn't one of the
+looked up by default") attempted to set blsdir if /boot/loader/entries was
+not the real path of the directory containing the BLS snippets. Which may
+be the case if for example /boot/loader/entries is in a btrfs subvolume.
+
+But in the case of ostree, /boot/loader is a symlink to the directory with
+the entries for the current deployment. So with ostree the blsdir will be
+wrongly set, since GRUB is able to follow the symlinks just fine. In fact,
+it has to follow the symlink since otherwise GRUB will always use the BLS
+files for the deployment that the symlink pointed out when blsdir was set.
+
+So only set blsdir if /boot/loader/entries is in a btrfs or zfs partition.
+
+Related: rhbz#1688453
+
+Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
+---
+ util/grub.d/10_linux.in     | 3 ++-
+ util/grub.d/10_linux_bls.in | 3 ++-
+ 2 files changed, 4 insertions(+), 2 deletions(-)
+
+diff --git a/util/grub.d/10_linux.in b/util/grub.d/10_linux.in
+index 2547dd52115..8f7ecf65df9 100644
+--- a/util/grub.d/10_linux.in
++++ b/util/grub.d/10_linux.in
+@@ -169,7 +169,8 @@ EOF
+ 
+     if [ "x${GRUB_GRUBENV_UPDATE}" = "xyes" ]; then
+         blsdir="/boot/loader/entries"
+-        if [ -d "${blsdir}" ]; then
++        [ -d "${blsdir}" ] && GRUB_BLS_FS="$(${grub_probe} --target=fs ${blsdir})"
++        if [ "x${GRUB_BLS_FS}" = "xbtrfs" ] || [ "x${GRUB_BLS_FS}" = "xzfs" ]; then
+             blsdir=$(make_system_path_relative_to_its_root "${blsdir}")
+             if [ "x${blsdir}" != "x/loader/entries" ] && [ "x${blsdir}" != "x/boot/loader/entries" ]; then
+                 ${grub_editenv} - set blsdir="${blsdir}"
+diff --git a/util/grub.d/10_linux_bls.in b/util/grub.d/10_linux_bls.in
+index 47b87c8a14b..1707e86f2d3 100644
+--- a/util/grub.d/10_linux_bls.in
++++ b/util/grub.d/10_linux_bls.in
+@@ -227,7 +227,8 @@ linux_entry ()
+ 
+     if [ "x${GRUB_GRUBENV_UPDATE}" = "xyes" ]; then
+         blsdir="/boot/loader/entries"
+-        if [ -d "${blsdir}" ]; then
++        [ -d "${blsdir}" ] && GRUB_BLS_FS="$(${grub_probe} --target=fs ${blsdir})"
++        if [ "x${GRUB_BLS_FS}" = "xbtrfs" ] || [ "x${GRUB_BLS_FS}" = "xzfs" ]; then
+             blsdir=$(make_system_path_relative_to_its_root "${blsdir}")
+             if [ "x${blsdir}" != "x/loader/entries" ] && [ "x${blsdir}" != "x/boot/loader/entries" ]; then
+                 ${grub_editenv} - set blsdir="${blsdir}"

grub.patches

@@ -283,3 +283,4 @@ Patch0282: 0282-Set-blsdir-if-the-BLS-directory-path-isn-t-one-of-th.patch
 Patch0283: 0283-Check-if-blsdir-exists-before-attempting-to-get-it-s.patch
 Patch0284: 0284-blscfg-fallback-to-default_kernelopts-if-BLS-option-.patch
 Patch0285: 0285-grub-switch-to-blscfg-copy-increment.mod-for-legacy-.patch
+Patch0286: 0286-Only-set-blsdir-if-boot-loader-entries-is-in-a-btrfs.patch

grub2.spec

@@ -7,7 +7,7 @@
 Name:		grub2
 Epoch:		1
 Version:	2.02
-Release:	72%{?dist}
+Release:	73%{?dist}
 Summary:	Bootloader with support for Linux, Multiboot and more
 License:	GPLv3+
 URL:		http://www.gnu.org/software/grub/
@@ -480,6 +480,10 @@ rm -r /boot/grub2.tmp/ || :
 %endif
 
 %changelog
+* Wed Mar 20 2019 Javier Martinez Canillas <javierm@redhat.com> - 2.02-73
+- Only set blsdir if /boot/loader/entries is in a btrfs or zfs partition
+  Related: rhbz#1688453
+
 * Mon Mar 11 2019 Javier Martinez Canillas <javierm@redhat.com> - 2.02-72
 - Avoid grub2-efi package to overwrite existing /boot/grub2/grubenv file
   Resolves: rhbz#1687323