rear/rear-skip-useless-xfs-mount-options-RHEL-10478.patch
2024-02-02 09:27:32 +01:00

86 lines
4.5 KiB
Diff

diff --git a/usr/share/rear/layout/prepare/GNU/Linux/133_include_mount_filesystem_code.sh b/usr/share/rear/layout/prepare/GNU/Linux/133_include_mount_filesystem_code.sh
index d57077791..87ab5d691 100644
--- a/usr/share/rear/layout/prepare/GNU/Linux/133_include_mount_filesystem_code.sh
+++ b/usr/share/rear/layout/prepare/GNU/Linux/133_include_mount_filesystem_code.sh
@@ -29,6 +29,7 @@ mount_fs() {
case $name in
(options)
# Do not mount nodev, as chrooting later on would fail:
+ # FIXME: naive approach, will replace any "nodev" inside longer options/values
value=${value//nodev/dev}
# btrfs mount options like subvolid=259 or subvol=/@/.snapshots/1/snapshot
# from the old system cannot work here for recovery because btrfs subvolumes
@@ -147,6 +148,27 @@ mount_fs() {
echo "mount $mountopts,remount,user_xattr $device $TARGET_FS_ROOT$mountpoint"
) >> "$LAYOUT_CODE"
;;
+ (xfs)
+ # remove logbsize=... mount option. It is a purely performance/memory usage optimization option,
+ # which can lead to mount failures, because it must be an integer multiple of the log stripe unit
+ # and the log stripe unit can be different in the recreated filesystem from the original filesystem
+ # (for example when using MKFS_XFS_OPTIONS, or in some exotic situations involving an old filesystem,
+ # see GitHub issue #2777 ).
+ # If logbsize is not an integer multiple of the log stripe unit, mount fails with the warning
+ # "XFS (...): logbuf size must be greater than or equal to log stripe size"
+ # in the kernel log
+ # (and a confusing error message
+ # "mount: ...: wrong fs type, bad option, bad superblock on ..., missing codepage or helper program, or other error."
+ # from the mount command), causing the layout restoration in the recovery process to fail.
+ # Wrong sunit/swidth can cause mount to fail as well, with this in the kernel log:
+ # "kernel: XFS (...): alignment check failed: sunit/swidth vs. agsize",
+ # so remove the sunit=.../swidth=... mount options as well.
+ mountopts="$( remove_mount_options_values "$mountopts" logbsize sunit swidth )"
+ (
+ echo "mkdir -p $TARGET_FS_ROOT$mountpoint"
+ echo "mount $mountopts $device $TARGET_FS_ROOT$mountpoint"
+ ) >> "$LAYOUT_CODE"
+ ;;
(*)
(
echo "mkdir -p $TARGET_FS_ROOT$mountpoint"
diff --git a/usr/share/rear/lib/filesystems-functions.sh b/usr/share/rear/lib/filesystems-functions.sh
index afdd3f24c..658d757f4 100644
--- a/usr/share/rear/lib/filesystems-functions.sh
+++ b/usr/share/rear/lib/filesystems-functions.sh
@@ -239,3 +239,40 @@ function xfs_parse
# Output xfs options for further use
echo "$xfs_opts"
}
+
+
+# $1 is a mount command argument (string containing comma-separated
+# mount options). The remaining arguments to the function ($2 ... )
+# specify the mount options to remove from $1, together with a trailing "="
+# and any value that follows each option.
+# For example, the call
+# "remove_mount_options_values nodev,uid=1,rw,gid=1 uid gid"
+# returns "nodev,rw".
+# There is no support for removing a mount option without a value and "=",
+# so "remove_mount_options_values nodev,uid=1,rw,gid=1 rw" will not work.
+# The function will return the modified string on stdout.
+
+function remove_mount_options_values () {
+ local str="$1"
+
+ shift
+ # First add a comma at the end so that it is easier to remove a mount option at the end:
+ str="${str/%/,}"
+ for i in "$@" ; do
+ # FIXME this also removes trailing strings at the end of longer words
+ # For example if one wants to remove any id=... option,
+ # the function will also replace "uid=1" by "u" by removing
+ # the trailing "id=1", which is not intended.
+ # Not easy to fix because $str can contain prefixes which are not
+ # mount options but arguments to the mount command itself
+ # (in particluar, "-o ").
+ # FIXME this simple approach would fail in case of mount options
+ # containing commas, for example the "context" option values,
+ # see mount(8)
+
+ # the extglob shell option is enabled in rear
+ str="${str//$i=*([^,]),/}"
+ done
+ # Remove all commas at the end:
+ echo "${str/%,/}"
+}