Root hash generalize by tlaurion · Pull Request #2067 · linuxboot/heads

tlaurion · 2026-03-06T16:08:08Z

merge Replace fdisk -l with sysfs-based disk enumeration (2tb+ drive support) #2035 first

Compatible with

pureos 10.3
debian-13
ubuntu-25.10 (LUKS+LVM based default installs from DVD livecd, bootable from TPM DUK to mitigate Ubuntu 24.04 LTS/24.10 misses efifb in initramfs (upstream bug: WON'T FIX?!?!?!) #1641)
QubesOS (untested yet since I use btrfs partition scheme and heads doesn't have btrfs-tools until Btrfs support in Heads recovery console #1939)
Fedora-43 default partition scheme is btrfs as well, so doesn't work there as for all btrfs default installs until Btrfs support in Heads recovery console #1939 (and Further optimization for space (-Os -> -Oz): musl-cross-make-> bump to gcc 15.1.0 & related changes #1991 merge to gain some needed space.

Meanwhile users have to specify LUKS+LVM from DVD live installers and dodge BTRFS partiton schemes

adds whole stack trace when in DEBUG mode, improving Improve TRACE_FUNC/ DEBUG_STACK helper functions so that whole stack trace is given on console when TRACE+DEBUG mode is on #1933

Copilot

Pull request overview

This PR updates Heads initrd utilities to better support varied Linux distros and storage layouts by improving disk info display (avoiding busybox fdisk limits) and generalizing root-hash handling across more LVM naming schemes.

Changes:

Replace fdisk -l parsing with a new sysfs-based disk_info_sysfs() helper for System Info disk display.
Improve LVM VG/LV handling to support non-root LV names (e.g., Ubuntu-style layouts) and enhance debug tracing.
Refine boot/root detection flow with additional logging and a fast-path when /boot is already mounted.

Reviewed changes

Copilot reviewed 2 out of 4 changed files in this pull request and generated 3 comments.

File	Description
initrd/etc/gui_functions	System Info now prints disk sizes via `disk_info_sysfs()` rather than parsing `fdisk`.
initrd/etc/functions	Adds `disk_info_sysfs()`; adjusts LVM VG discovery parsing; refactors GPT BIOS/GRUB detection and boot-device detection logging.
initrd/bin/root-hashes-gui.sh	Adds tracing/debug; generalizes LVM root LV selection and LVM cleanup behavior.
initrd/bin/oem-system-info-xx30	System Info screen now uses `disk_info_sysfs()` for disk listing.

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

initrd/etc/gui_functions

initrd/etc/functions

Copilot

Pull request overview

Copilot reviewed 2 out of 4 changed files in this pull request and generated no new comments.

Comments suppressed due to low confidence (1)

initrd/etc/functions:1378

mount_possible_boot_device declares local PARTITION_TYPE but never uses it, and assigns to sectors without declaring it local. This leaves a global sectors variable in the shared /etc/functions environment and adds dead code. Make sectors local (and remove PARTITION_TYPE if no longer needed) to avoid accidental cross-function coupling.

	local BOOT_DEV="$1"
	local PARTITION_TYPE

	# Unmount anything on /boot.  Ignore failure since there might not be
	# anything.  If there is something mounted and we cannot unmount it for
	# some reason, mount will fail, which is handled.
	umount /boot 2>/dev/null || true

	# Skip bios-grub partitions on GPT disks, LUKS partitions, and LVM PVs,
	# we can't mount these as /boot.
	# Skip partitions we definitely can't mount for /boot.  Log each reason.
	if is_gpt_bios_grub "$BOOT_DEV"; then
		DEBUG "$BOOT_DEV is GPT BIOS/GRUB partition, skipping"
		return 1
	fi
	if cryptsetup isLuks "$BOOT_DEV"; then
		DEBUG "$BOOT_DEV is a LUKS volume, skipping"
		return 1
	fi
	if find_lvm_vg_name "$BOOT_DEV" >/dev/null; then
		DEBUG "$BOOT_DEV is an LVM PV, skipping"
		return 1
	fi

	# Get the size of BOOT_DEV in 512-byte sectors
	sectors=$(blockdev --getsz "$BOOT_DEV")

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

Copilot

Pull request overview

Copilot reviewed 1 out of 2 changed files in this pull request and generated 1 comment.

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

initrd/etc/functions

… enabled Signed-off-by: Thierry Laurion <[email protected]>

Compared to HEAD^, this commit updates initrd root-hash probing in: - initrd/bin/root-hashes-gui.sh - initrd/etc/functions Behavior expected to work: - Root-hash create/verify flow on latest Ubuntu, Debian, and PureOS under KVM. - LUKS/LVM root probing based on mountability + expected root directory checks. - Clear unsupported-layout whiptail guidance for unsupported filesystem/layout combinations. Current status and non-goals: - Fedora and QubesOS are untested in this change set. - QubesOS on coreboot q35 with Heads still does not support qemu/kvm; no regression is implied. Signed-off-by: Thierry Laurion <[email protected]>

Copilot

Pull request overview

Copilot reviewed 1 out of 2 changed files in this pull request and generated 2 comments.

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

Copilot · 2026-03-06T21:16:12Z

initrd/etc/functions

 	mkdir -p /tmp/root-hashes-gui
-	if ! lvm pvs --noheadings -o vg_name "$DEVICE" >/tmp/root-hashes-gui/lvm_vg 2>/dev/null; then
-		# It's not an LVM PV
+	# Try to query whether DEVICE is an LVM physical volume.  On systems
+	# without LVM the command may not exist; treat that like "not a PV".
+	if ! lvm pvs --noheadings -o vg_name "$DEVICE" >/tmp/root-hashes-gui/lvm_vg 2>/tmp/root-hashes-gui/lvm_err; then
+		# It's not an LVM PV, or lvm failed entirely.  Log stderr for debugging.
+		DEBUG "lvm pvs failed for $DEVICE, stderr:" "$(cat /tmp/root-hashes-gui/lvm_err)"


find_lvm_vg_name() writes its scratch output under /tmp/root-hashes-gui/* even though it lives in the shared /etc/functions library. This creates a hard coupling to the root-hashes flow and can also clobber data if another caller uses the same path. Consider using a more generic per-function temp dir (or mktemp) so /etc/functions utilities remain reusable.

Copilot · 2026-03-06T21:16:13Z

initrd/etc/functions

+case "${TRACE_STACK}" in
+*"main($0:"*)
+	;;
+*)
+	TRACE_STACK="${TRACE_STACK:+$TRACE_STACK -> }main($0:0)"
+	export TRACE_STACK
+	;;
+esac


The TRACE_STACK header comment says it appends the script name/line, but the code always records ":0" (TRACE_STACK="...main($0:0)"). Consider capturing the actual source location (e.g., using BASH_SOURCE[1] and BASH_LINENO[0]) so traces are accurate and match the documented format.

Suggested change

case "${TRACE_STACK}" in

*"main($0:"*)

;;

*)

TRACE_STACK="${TRACE_STACK:+$TRACE_STACK -> }main($0:0)"

export TRACE_STACK

;;

esac

# Determine the calling script and line, if available.

if [ "${#BASH_SOURCE[@]}" -ge 2 ]; then

_TRACE_SRC="${BASH_SOURCE[1]}"

else

_TRACE_SRC="$0"

fi

if [ "${#BASH_LINENO[@]}" -ge 1 ]; then

_TRACE_LINE="${BASH_LINENO[0]}"

else

_TRACE_LINE=0

fi

_TRACE_ENTRY="main(${_TRACE_SRC}:${_TRACE_LINE})"

case "${TRACE_STACK}" in

*"${_TRACE_ENTRY}"*)

;;

*)

TRACE_STACK="${TRACE_STACK:+$TRACE_STACK -> }${_TRACE_ENTRY}"

export TRACE_STACK

;;

esac

unset _TRACE_SRC _TRACE_LINE _TRACE_ENTRY

Copilot AI review requested due to automatic review settings March 6, 2026 16:08

Copilot started reviewing on behalf of tlaurion March 6, 2026 16:08 View session

tlaurion mentioned this pull request Mar 6, 2026

UX improvements: TPM reseal (HOTP/TOTP/DUK) adds integrity report; detects disk/tpm swap and guide user into action #2068

Draft

12 tasks

Copilot AI reviewed Mar 6, 2026

View reviewed changes

initrd/etc/gui_functions Show resolved Hide resolved

initrd/etc/functions Outdated Show resolved Hide resolved

initrd/etc/functions Show resolved Hide resolved

tlaurion force-pushed the root-hash_generalize branch 2 times, most recently from 293a8d9 to ff96aef Compare March 6, 2026 17:37

tlaurion requested a review from Copilot March 6, 2026 17:38

Copilot started reviewing on behalf of tlaurion March 6, 2026 17:38 View session

Copilot AI reviewed Mar 6, 2026

View reviewed changes

tlaurion added bug security UX feature freeze 2026-04 labels Mar 6, 2026

tlaurion force-pushed the root-hash_generalize branch from ff96aef to 6ab7d10 Compare March 6, 2026 20:51

tlaurion requested a review from Copilot March 6, 2026 20:54

Copilot started reviewing on behalf of tlaurion March 6, 2026 20:54 View session

Copilot AI reviewed Mar 6, 2026

View reviewed changes

initrd/etc/functions Show resolved Hide resolved

tlaurion force-pushed the root-hash_generalize branch from 6ab7d10 to 2aa58a0 Compare March 6, 2026 21:04

tlaurion requested a review from Copilot March 6, 2026 21:05

tlaurion force-pushed the root-hash_generalize branch 2 times, most recently from a2981bc to 8d03b23 Compare March 6, 2026 21:07

Copilot started reviewing on behalf of tlaurion March 6, 2026 21:07 View session

tlaurion added 2 commits March 6, 2026 16:09

functions: add full track tracing when doing TRACE_FUNC when DEBUG is…

c37f96d

… enabled Signed-off-by: Thierry Laurion <[email protected]>

tlaurion force-pushed the root-hash_generalize branch from 8d03b23 to 9d03303 Compare March 6, 2026 21:09

tlaurion merged commit 2ab9ff3 into linuxboot:master Mar 6, 2026
1 of 2 checks passed

Copilot AI reviewed Mar 6, 2026

View reviewed changes

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

Root hash generalize#2067

Root hash generalize#2067
tlaurion merged 2 commits intolinuxboot:masterfrom
tlaurion:root-hash_generalize

tlaurion commented Mar 6, 2026 •

edited

Loading

Uh oh!

Copilot AI left a comment

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Copilot AI left a comment

Uh oh!

Copilot AI left a comment

Uh oh!

Uh oh!

Uh oh!

Copilot AI left a comment

Uh oh!

Copilot AI Mar 6, 2026

Uh oh!

Copilot AI Mar 6, 2026

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

2 participants

-case "${TRACE_STACK}" in
-*"main($0:"*)
-	;;
-*)
-	TRACE_STACK="${TRACE_STACK:+$TRACE_STACK -> }main($0:0)"
-	export TRACE_STACK
-	;;
-esac
+# Determine the calling script and line, if available.
+if [ "${#BASH_SOURCE[@]}" -ge 2 ]; then
+	_TRACE_SRC="${BASH_SOURCE[1]}"
+else
+	_TRACE_SRC="$0"
+fi
+if [ "${#BASH_LINENO[@]}" -ge 1 ]; then
+	_TRACE_LINE="${BASH_LINENO[0]}"
+else
+	_TRACE_LINE=0
+fi
+_TRACE_ENTRY="main(${_TRACE_SRC}:${_TRACE_LINE})"
+case "${TRACE_STACK}" in
+*"${_TRACE_ENTRY}"*)
+	;;
+*)
+	TRACE_STACK="${TRACE_STACK:+$TRACE_STACK -> }${_TRACE_ENTRY}"
+	export TRACE_STACK
+	;;
+esac
+unset _TRACE_SRC _TRACE_LINE _TRACE_ENTRY

Uh oh!

Conversation

tlaurion commented Mar 6, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

Copilot AI left a comment

Choose a reason for hiding this comment

Pull request overview

Reviewed changes

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Copilot AI left a comment

Choose a reason for hiding this comment

Pull request overview

Uh oh!

Copilot AI left a comment

Choose a reason for hiding this comment

Pull request overview

Uh oh!

Uh oh!

Uh oh!

Copilot AI left a comment

Choose a reason for hiding this comment

Pull request overview

Uh oh!

Copilot AI Mar 6, 2026

Choose a reason for hiding this comment

Uh oh!

Copilot AI Mar 6, 2026

Choose a reason for hiding this comment

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

2 participants

tlaurion commented Mar 6, 2026 •

edited

Loading