6b2dd0f731
Signed-off-by: Peter Jones <pjones@redhat.com>
244 lines
12 KiB
Diff
244 lines
12 KiB
Diff
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
|
|
From: Nicholas Vinson <nvinson234@gmail.com>
|
|
Date: Mon, 16 Apr 2018 22:36:26 -0700
|
|
Subject: [PATCH] templates: Update grub script template files
|
|
|
|
Update grub-mkconfig.in and 10_linux.in to support grub-probe's new
|
|
partuuid target. Update grub.texi documentation. The following table
|
|
shows how GRUB_DISABLE_LINUX_UUID, GRUB_DISABLE_LINUX_PARTUUID, and
|
|
initramfs detection interact:
|
|
|
|
Initramfs GRUB_DISABLE_LINUX_PARTUUID GRUB_DISABLE_LINUX_UUID Linux Root
|
|
detected Set Set ID Method
|
|
|
|
false false false part UUID
|
|
false false true part UUID
|
|
false true false dev name
|
|
false true true dev name
|
|
true false false fs UUID
|
|
true false true part UUID
|
|
true true false fs UUID
|
|
true true true dev name
|
|
|
|
Note: GRUB_DISABLE_LINUX_PARTUUID and GRUB_DISABLE_LINUX_UUID equate to
|
|
'false' when unset or set to any value other than 'true'.
|
|
GRUB_DISABLE_LINUX_PARTUUID defaults to 'true'.
|
|
|
|
Signed-off-by: Nicholas Vinson <nvinson234@gmail.com>
|
|
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
|
|
---
|
|
docs/grub.texi | 67 ++++++++++++++++++++++++++++++++++++++++++---
|
|
util/grub-mkconfig.in | 3 ++
|
|
util/grub.d/10_linux.in | 22 +++++++++++++--
|
|
util/grub.d/20_linux_xen.in | 22 +++++++++++++--
|
|
4 files changed, 104 insertions(+), 10 deletions(-)
|
|
|
|
diff --git a/docs/grub.texi b/docs/grub.texi
|
|
index 0f2ab91fc69..2adfa97bee8 100644
|
|
--- a/docs/grub.texi
|
|
+++ b/docs/grub.texi
|
|
@@ -1214,10 +1214,11 @@ GRUB is configured using @file{grub.cfg}, usually located under
|
|
need to write the whole thing by hand.
|
|
|
|
@menu
|
|
-* Simple configuration:: Recommended for most users
|
|
-* Shell-like scripting:: For power users and developers
|
|
-* Multi-boot manual config:: For non-standard multi-OS scenarios
|
|
-* Embedded configuration:: Embedding a configuration file into GRUB
|
|
+* Simple configuration:: Recommended for most users
|
|
+* Root Identifcation Heuristics:: Summary on how the root file system is identified.
|
|
+* Shell-like scripting:: For power users and developers
|
|
+* Multi-boot manual config:: For non-standard multi-OS scenarios
|
|
+* Embedded configuration:: Embedding a configuration file into GRUB
|
|
@end menu
|
|
|
|
|
|
@@ -1425,6 +1426,17 @@ the Linux kernel, using a @samp{root=UUID=...} kernel parameter. This is
|
|
usually more reliable, but in some cases it may not be appropriate. To
|
|
disable the use of UUIDs, set this option to @samp{true}.
|
|
|
|
+@item GRUB_DISABLE_LINUX_PARTUUID
|
|
+If @command{grub-mkconfig} cannot identify the root filesystem via its
|
|
+universally-unique indentifier (UUID), @command{grub-mkconfig} can use the UUID
|
|
+of the partition containing the filesystem to identify the root filesystem to
|
|
+the Linux kernel via a @samp{root=PARTUUID=...} kernel parameter. This is not
|
|
+as reliable as using the filesystem UUID, but is more reliable than using the
|
|
+Linux device names. When @samp{GRUB_DISABLE_LINUX_PARTUUID} is set to
|
|
+@samp{false}, the Linux kernel version must be 2.6.37 (3.10 for systems using
|
|
+the MSDOS partition scheme) or newer. This option defaults to @samp{true}. To
|
|
+enable the use of partition UUIDs, set this option to @samp{false}.
|
|
+
|
|
@item GRUB_DISABLE_RECOVERY
|
|
If this option is set to @samp{true}, disable the generation of recovery
|
|
mode menu entries.
|
|
@@ -1556,6 +1568,53 @@ edit the scripts in @file{/etc/grub.d} directly.
|
|
menu entries; simply type the menu entries you want to add at the end of
|
|
that file, making sure to leave at least the first two lines intact.
|
|
|
|
+@node Root Identifcation Heuristics
|
|
+@section Root Identifcation Heuristics
|
|
+If the target operating system uses the Linux kernel, @command{grub-mkconfig}
|
|
+attempts to identify the root file system via a heuristic algoirthm. This
|
|
+algorithm selects the identification method of the root file system by
|
|
+considering three factors. The first is if an initrd for the target operating
|
|
+system is also present. The second is @samp{GRUB_DISABLE_LINUX_UUID} and if set
|
|
+to @samp{true}, prevents @command{grub-mkconfig} from identifying the root file
|
|
+system by its UUID. The third is @samp{GRUB_DISABLE_LINUX_PARTUUID} and if set
|
|
+to @samp{true}, prevents @command{grub-mkconfig} from identifying the root file
|
|
+system via the UUID of its enclosing partition. If the variables are assigned
|
|
+any other value, that value is considered equivalent to @samp{false}. The
|
|
+variables are also considered to be set to @samp{false} if they are not set.
|
|
+
|
|
+When booting, the Linux kernel will delegate the task of mounting the root
|
|
+filesystem to the initrd. Most initrd images determine the root file system by
|
|
+checking the Linux kernel's command-line for the @samp{root} key and use its
|
|
+value as the identification method of the root file system. To improve the
|
|
+reliability of booting, most initrd images also allow the root file system to be
|
|
+identified by its UUID. Because of this behavior, the @command{grub-mkconfig}
|
|
+command will set @samp{root} to @samp{root=UUID=...} to provide the initrd with
|
|
+the filesystem UUID of the root file system.
|
|
+
|
|
+If no initrd is detected or @samp{GRUB_DISABLE_LINUX_UUID} is set to @samp{true}
|
|
+then @command{grub-command} will identify the root filesystem by setting the
|
|
+kernel command-line variable @samp{root} to @samp{root=PARTUUID=...} unless
|
|
+@samp{GRUB_DISABLE_LINUX_PARTUUID} is also set to @samp{true}. If
|
|
+@samp{GRUB_DISABLE_LINUX_PARTUUID} is also set to @samp{true},
|
|
+@command{grub-command} will identify by its Linux device name.
|
|
+
|
|
+The following table summarizes the behavior of the @command{grub-mkconfig}
|
|
+command.
|
|
+
|
|
+@multitable {detected} {GRUB_DISABLE_LINUX_PARTUUID} {GRUB_DISABLE_LINUX_UUID} {Linux Root}
|
|
+@headitem Initrd detected @tab GRUB_DISABLE_LINUX_PARTUUID Set To @tab GRUB_DISABLE_LINUX_UUID Set To @tab Linux Root ID Method
|
|
+@item false @tab false @tab false @tab part UUID
|
|
+@item false @tab false @tab true @tab part UUID
|
|
+@item false @tab true @tab false @tab dev name
|
|
+@item false @tab true @tab true @tab dev name
|
|
+@item true @tab false @tab false @tab fs UUID
|
|
+@item true @tab false @tab true @tab part UUID
|
|
+@item true @tab true @tab false @tab fs UUID
|
|
+@item true @tab true @tab true @tab dev name
|
|
+@end multitable
|
|
+
|
|
+Remember, @samp{GRUB_DISABLE_LINUX_PARTUUID} and @samp{GRUB_DISABLE_LINUX_UUID}
|
|
+are also considered to be set to @samp{false} when they are unset.
|
|
|
|
@node Shell-like scripting
|
|
@section Writing full configuration files directly
|
|
diff --git a/util/grub-mkconfig.in b/util/grub-mkconfig.in
|
|
index 35ef583b05f..33332360eec 100644
|
|
--- a/util/grub-mkconfig.in
|
|
+++ b/util/grub-mkconfig.in
|
|
@@ -134,6 +134,7 @@ fi
|
|
# Device containing our userland. Typically used for root= parameter.
|
|
GRUB_DEVICE="`${grub_probe} --target=device /`"
|
|
GRUB_DEVICE_UUID="`${grub_probe} --device ${GRUB_DEVICE} --target=fs_uuid 2> /dev/null`" || true
|
|
+GRUB_DEVICE_PARTUUID="`${grub_probe} --device ${GRUB_DEVICE} --target=partuuid 2> /dev/null`" || true
|
|
|
|
# Device containing our /boot partition. Usually the same as GRUB_DEVICE.
|
|
GRUB_DEVICE_BOOT="`${grub_probe} --target=device /boot`"
|
|
@@ -188,6 +189,7 @@ if [ "x${GRUB_ACTUAL_DEFAULT}" = "xsaved" ] ; then GRUB_ACTUAL_DEFAULT="`"${grub
|
|
# override them.
|
|
export GRUB_DEVICE \
|
|
GRUB_DEVICE_UUID \
|
|
+ GRUB_DEVICE_PARTUUID \
|
|
GRUB_DEVICE_BOOT \
|
|
GRUB_DEVICE_BOOT_UUID \
|
|
GRUB_FS \
|
|
@@ -223,6 +225,7 @@ export GRUB_DEFAULT \
|
|
GRUB_TERMINAL_OUTPUT \
|
|
GRUB_SERIAL_COMMAND \
|
|
GRUB_DISABLE_LINUX_UUID \
|
|
+ GRUB_DISABLE_LINUX_PARTUUID \
|
|
GRUB_DISABLE_RECOVERY \
|
|
GRUB_VIDEO_BACKEND \
|
|
GRUB_GFXMODE \
|
|
diff --git a/util/grub.d/10_linux.in b/util/grub.d/10_linux.in
|
|
index faedf74e14e..146499f22fd 100644
|
|
--- a/util/grub.d/10_linux.in
|
|
+++ b/util/grub.d/10_linux.in
|
|
@@ -43,12 +43,22 @@ case ${GRUB_DEVICE} in
|
|
;;
|
|
esac
|
|
|
|
+# Default to disabling partition uuid support to maintian compatibility with
|
|
+# older kernels.
|
|
+GRUB_DISABLE_LINUX_PARTUUID=${GRUB_DISABLE_LINUX_PARTUUID-true}
|
|
+
|
|
# btrfs may reside on multiple devices. We cannot pass them as value of root= parameter
|
|
# and mounting btrfs requires user space scanning, so force UUID in this case.
|
|
-if [ "x${GRUB_DEVICE_UUID}" = "x" ] || [ "x${GRUB_DISABLE_LINUX_UUID}" = "xtrue" ] \
|
|
- || ! test -e "/dev/disk/by-uuid/${GRUB_DEVICE_UUID}" \
|
|
+if ( [ "x${GRUB_DEVICE_UUID}" = "x" ] && [ "x${GRUB_DEVICE_PARTUUID}" = "x" ) \
|
|
+ || ( [ "x${GRUB_DISABLE_LINUX_UUID}" = "xtrue" ] \
|
|
+ && [ "x${GRUB_DISABLE_LINUX_PARTUUID}" = "xtrue" ] ) \
|
|
+ || ( ! test -e "/dev/disk/by-uuid/${GRUB_DEVICE_UUID}" \
|
|
+ && ! test -e "/dev/disk/by-partuuid/${GRUB_DEVICE_PARTUUID}" ) \
|
|
|| ( test -e "${GRUB_DEVICE}" && uses_abstraction "${GRUB_DEVICE}" lvm ); then
|
|
LINUX_ROOT_DEVICE=${GRUB_DEVICE}
|
|
+elif [ "x${GRUB_DEVICE_UUID}" = "x" ] \
|
|
+ || [ "x${GRUB_DISABLE_LINUX_UUID}" = "xtrue" ]; then
|
|
+ LINUX_ROOT_DEVICE=PARTUUID=${GRUB_DEVICE_PARTUUID}
|
|
else
|
|
LINUX_ROOT_DEVICE=UUID=${GRUB_DEVICE_UUID}
|
|
fi
|
|
@@ -242,7 +252,13 @@ while [ "x$list" != "x" ] ; do
|
|
if test -z "${initramfs}" && test -z "${initrd_real}" ; then
|
|
# "UUID=" and "ZFS=" magic is parsed by initrd or initramfs. Since there's
|
|
# no initrd or builtin initramfs, it can't work here.
|
|
- linux_root_device_thisversion=${GRUB_DEVICE}
|
|
+ if [ "x${GRUB_DEVICE_PARTUUID}" = "x" ] \
|
|
+ || [ "x${GRUB_DISABLE_LINUX_PARTUUID}" = "xtrue" ]; then
|
|
+
|
|
+ linux_root_device_thisversion=${GRUB_DEVICE}
|
|
+ else
|
|
+ linux_root_device_thisversion=PARTUUID=${GRUB_DEVICE_PARTUUID}
|
|
+ fi
|
|
fi
|
|
|
|
if [ "x$is_top_level" = xtrue ] && [ "x${GRUB_DISABLE_SUBMENU}" != xy ]; then
|
|
diff --git a/util/grub.d/20_linux_xen.in b/util/grub.d/20_linux_xen.in
|
|
index 0cb0f4e49b9..e8143b079dc 100644
|
|
--- a/util/grub.d/20_linux_xen.in
|
|
+++ b/util/grub.d/20_linux_xen.in
|
|
@@ -43,12 +43,22 @@ case ${GRUB_DEVICE} in
|
|
;;
|
|
esac
|
|
|
|
+# Default to disabling partition uuid support to maintian compatibility with
|
|
+# older kernels.
|
|
+GRUB_DISABLE_LINUX_PARTUUID=${GRUB_DISABLE_LINUX_PARTUUID-true}
|
|
+
|
|
# btrfs may reside on multiple devices. We cannot pass them as value of root= parameter
|
|
# and mounting btrfs requires user space scanning, so force UUID in this case.
|
|
-if [ "x${GRUB_DEVICE_UUID}" = "x" ] || [ "x${GRUB_DISABLE_LINUX_UUID}" = "xtrue" ] \
|
|
- || ! test -e "/dev/disk/by-uuid/${GRUB_DEVICE_UUID}" \
|
|
+if ( [ "x${GRUB_DEVICE_UUID}" = "x" ] && [ "x${GRUB_DEVICE_PARTUUID}" = "x" ] ) \
|
|
+ || ( [ "x${GRUB_DISABLE_LINUX_UUID}" = "xtrue" ] \
|
|
+ && [ "x${GRUB_DISABLE_LINUX_PARTUUID}" = "xtrue" ] ) \
|
|
+ || ( ! test -e "/dev/disk/by-uuid/${GRUB_DEVICE_UUID}" \
|
|
+ && ! test -e "/dev/disk/by-partuuid/${GRUB_DEVICE_PARTUUID}" ) \
|
|
|| ( test -e "${GRUB_DEVICE}" && uses_abstraction "${GRUB_DEVICE}" lvm ); then
|
|
LINUX_ROOT_DEVICE=${GRUB_DEVICE}
|
|
+elif [ "x${GRUB_DEVICE_UUID}" = "x" ] \
|
|
+ || [ "x${GRUB_DISABLE_LINUX_UUID}" = "xtrue" ]; then
|
|
+ LINUX_ROOT_DEVICE=PARTUUID=${GRUB_DEVICE_PARTUUID}
|
|
else
|
|
LINUX_ROOT_DEVICE=UUID=${GRUB_DEVICE_UUID}
|
|
fi
|
|
@@ -246,7 +256,13 @@ while [ "x${xen_list}" != "x" ] ; do
|
|
gettext_printf "Found initrd image: %s\n" "${dirname}/${initrd}" >&2
|
|
else
|
|
# "UUID=" magic is parsed by initrds. Since there's no initrd, it can't work here.
|
|
- linux_root_device_thisversion=${GRUB_DEVICE}
|
|
+ if [ "x${GRUB_DEVICE_PARTUUID}" = "x" ] \
|
|
+ || [ "x${GRUB_DISABLE_LINUX_PARTUUID}" = "xtrue" ]; then
|
|
+
|
|
+ linux_root_device_thisversion=${GRUB_DEVICE}
|
|
+ else
|
|
+ linux_root_device_thisversion=PARTUUID=${GRUB_DEVICE_PARTUUID}
|
|
+ fi
|
|
fi
|
|
|
|
if [ "x$is_top_level" = xtrue ] && [ "x${GRUB_DISABLE_SUBMENU}" != xy ]; then
|