[PATCH v2 0/2] selftests/liveupdate: add end to end test infrastructure and scripts

[PATCH v2 0/2] selftests/liveupdate: add end to end test infrastructure and scripts

[Jordan Richards]

This patch series adds end to end testing infrastructure required to
verify the liveupdate feature, building and running the existing
selftests on supported architectures.

To support executing the selftests as part of an init process, this
patch series also adds ftruncate() to nolibc.

Changelog from v1 [1]:
- Moved ftruncate() wrapper to nolibc and fixed issue building selftests without nolibc
- Fixed handling of CROSS_COMPILE env variable
- Remove unecessary complexity in luo_test.sh
- Move results_* directory to selftests/liveupdate/

[1] https://lore.kernel.org/linux-mm/20260122214427.3568647-1-jordanrichards@google.com/

Jordan Richards (1):
  tools/nolibc: add ftruncate()

Pasha Tatashin (1):
  selftests/liveupdate: add end to end test infrastructure and scripts

 tools/include/nolibc/unistd.h                 |  11 +
 tools/testing/selftests/liveupdate/.gitignore |   1 +
 tools/testing/selftests/liveupdate/config     |   1 +
 .../selftests/liveupdate/config.aarch64       |   2 +
 .../selftests/liveupdate/config.x86_64        |   2 +
 tools/testing/selftests/liveupdate/init.c     | 179 ++++++++++++
 .../testing/selftests/liveupdate/luo_test.sh  | 276 ++++++++++++++++++
 .../selftests/liveupdate/luo_test_utils.c     |  27 +-
 tools/testing/selftests/liveupdate/run.sh     |  63 ++++
 9 files changed, 549 insertions(+), 13 deletions(-)
 create mode 100644 tools/testing/selftests/liveupdate/config.aarch64
 create mode 100644 tools/testing/selftests/liveupdate/config.x86_64
 create mode 100644 tools/testing/selftests/liveupdate/init.c
 create mode 100755 tools/testing/selftests/liveupdate/luo_test.sh
 create mode 100755 tools/testing/selftests/liveupdate/run.sh


base-commit: 145197c9801f90fed517447e24a9d20f3927cf27
--
2.53.0.rc2.204.g2597b5adb4-goog

[PATCH v2 1/2] tools/nolibc: add ftruncate()

[Jordan Richards]

---
 tools/include/nolibc/unistd.h | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/tools/include/nolibc/unistd.h b/tools/include/nolibc/unistd.h
index bb5e80f3f05d..845d10f48fd0 100644
--- a/tools/include/nolibc/unistd.h
+++ b/tools/include/nolibc/unistd.h
@@ -48,6 +48,17 @@ int access(const char *path, int amode)
 	return faccessat(AT_FDCWD, path, amode, 0);
 }
 
+static __attribute__((unused))
+int sys_ftruncate(int fd, off_t length)
+{
+	return my_syscall2(__NR_ftruncate, fd, length);
+}
+
+static __attribute__((unused))
+int ftruncate(int fd, off_t length)
+{
+	return __sysret(sys_ftruncate(fd, length));
+}
 
 static __attribute__((unused))
 int msleep(unsigned int msecs)
-- 
2.53.0.rc2.204.g2597b5adb4-goog

[PATCH v2 2/2] selftests/liveupdate: add end to end test infrastructure and scripts

[Jordan Richards]

From: Pasha Tatashin <pasha.tatashin@soleen.com>

Add the end to end testing infrastructure required to verify the
liveupdate feature. This includes a custom init process, a test
orchestration script, and a batch runner.

The framework consists of:

init.c:
A lightweight init process that manages the kexec lifecycle.
It mounts necessary filesystems, determines the current execution
stage (1 or 2) via the kernel command line, and handles the
kexec_file_load() sequence to transition between kernels.

luo_test.sh:
The primary KTAP-compliant test driver. It handles:
- Kernel configuration merging and building.
- Cross-compilation detection for x86_64 and arm64.
- Generation of the initrd containing the test binary and init.
- QEMU execution with automatic accelerator detection (KVM, HVF,
 or TCG).

run.sh:
A wrapper script to discover and execute all `luo_*.c`
tests across supported architectures, providing a summary of
pass/fail/skip results.

Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Jordan Richards <jordanrichards@google.com>
---
 tools/testing/selftests/liveupdate/.gitignore |   1 +
 tools/testing/selftests/liveupdate/config     |   1 +
 .../selftests/liveupdate/config.aarch64       |   2 +
 .../selftests/liveupdate/config.x86_64        |   2 +
 tools/testing/selftests/liveupdate/init.c     | 179 ++++++++++++
 .../testing/selftests/liveupdate/luo_test.sh  | 276 ++++++++++++++++++
 .../selftests/liveupdate/luo_test_utils.c     |  27 +-
 tools/testing/selftests/liveupdate/run.sh     |  63 ++++
 8 files changed, 538 insertions(+), 13 deletions(-)
 create mode 100644 tools/testing/selftests/liveupdate/config.aarch64
 create mode 100644 tools/testing/selftests/liveupdate/config.x86_64
 create mode 100644 tools/testing/selftests/liveupdate/init.c
 create mode 100755 tools/testing/selftests/liveupdate/luo_test.sh
 create mode 100755 tools/testing/selftests/liveupdate/run.sh

diff --git a/tools/testing/selftests/liveupdate/.gitignore b/tools/testing/selftests/liveupdate/.gitignore
index 661827083ab6..cb08ddb0dfee 100644
--- a/tools/testing/selftests/liveupdate/.gitignore
+++ b/tools/testing/selftests/liveupdate/.gitignore
@@ -6,4 +6,5 @@
 !*.sh
 !.gitignore
 !config
+!config.*
 !Makefile
diff --git a/tools/testing/selftests/liveupdate/config b/tools/testing/selftests/liveupdate/config
index 91d03f9a6a39..016d009dba13 100644
--- a/tools/testing/selftests/liveupdate/config
+++ b/tools/testing/selftests/liveupdate/config
@@ -1,4 +1,5 @@
 CONFIG_BLK_DEV_INITRD=y
+CONFIG_DEVTMPFS=y
 CONFIG_KEXEC_FILE=y
 CONFIG_KEXEC_HANDOVER=y
 CONFIG_KEXEC_HANDOVER_ENABLE_DEFAULT=y
diff --git a/tools/testing/selftests/liveupdate/config.aarch64 b/tools/testing/selftests/liveupdate/config.aarch64
new file mode 100644
index 000000000000..445716403925
--- /dev/null
+++ b/tools/testing/selftests/liveupdate/config.aarch64
@@ -0,0 +1,2 @@
+CONFIG_SERIAL_AMBA_PL011=y
+CONFIG_SERIAL_AMBA_PL011_CONSOLE=y
diff --git a/tools/testing/selftests/liveupdate/config.x86_64 b/tools/testing/selftests/liveupdate/config.x86_64
new file mode 100644
index 000000000000..810d9c9d213e
--- /dev/null
+++ b/tools/testing/selftests/liveupdate/config.x86_64
@@ -0,0 +1,2 @@
+CONFIG_SERIAL_8250=y
+CONFIG_SERIAL_8250_CONSOLE=y
diff --git a/tools/testing/selftests/liveupdate/init.c b/tools/testing/selftests/liveupdate/init.c
new file mode 100644
index 000000000000..fb08bd58b9b9
--- /dev/null
+++ b/tools/testing/selftests/liveupdate/init.c
@@ -0,0 +1,179 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * Copyright (c) 2025, Google LLC.
+ * Pasha Tatashin <pasha.tatashin@soleen.com>
+ */
+#include <fcntl.h>
+#include <linux/kexec.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mount.h>
+#include <sys/reboot.h>
+#include <sys/syscall.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#define COMMAND_LINE_SIZE 2048
+#define KERNEL_IMAGE "/kernel"
+#define INITRD_IMAGE "/initrd.img"
+#define TEST_BINARY "/test_binary"
+
+static int mount_filesystems(void)
+{
+	if (mount("devtmpfs", "/dev", "devtmpfs", 0, NULL) < 0) {
+		fprintf(stderr, "INIT: Warning: Failed to mount devtmpfs\n");
+		return -1;
+	}
+
+	if (mount("debugfs", "/debugfs", "debugfs", 0, NULL) < 0) {
+		fprintf(stderr, "INIT: Failed to mount debugfs\n");
+		return -1;
+	}
+
+	if (mount("proc", "/proc", "proc", 0, NULL) < 0) {
+		fprintf(stderr, "INIT: Failed to mount proc\n");
+		return -1;
+	}
+
+	return 0;
+}
+
+static long kexec_file_load(int kernel_fd, int initrd_fd,
+			    unsigned long cmdline_len, const char *cmdline,
+			    unsigned long flags)
+{
+	return syscall(__NR_kexec_file_load, kernel_fd, initrd_fd, cmdline_len,
+		       cmdline, flags);
+}
+
+static int kexec_load(void)
+{
+	char cmdline[COMMAND_LINE_SIZE];
+	int kernel_fd, initrd_fd, err;
+	ssize_t len;
+	int fd;
+
+	fd = open("/proc/cmdline", O_RDONLY);
+	if (fd < 0) {
+		fprintf(stderr, "INIT: Failed to read /proc/cmdline\n");
+
+		return -1;
+	}
+
+	len = read(fd, cmdline, sizeof(cmdline) - 1);
+	close(fd);
+	if (len < 0)
+		return -1;
+
+	cmdline[len] = 0;
+	if (len > 0 && cmdline[len - 1] == '\n')
+		cmdline[len - 1] = 0;
+
+	strncat(cmdline, " luo_stage=2", sizeof(cmdline) - strlen(cmdline) - 1);
+
+	kernel_fd = open(KERNEL_IMAGE, O_RDONLY);
+	if (kernel_fd < 0) {
+		fprintf(stderr, "INIT: Failed to open kernel image\n");
+		return -1;
+	}
+
+	initrd_fd = open(INITRD_IMAGE, O_RDONLY);
+	if (initrd_fd < 0) {
+		fprintf(stderr, "INIT: Failed to open initrd image\n");
+		close(kernel_fd);
+		return -1;
+	}
+
+	err = kexec_file_load(kernel_fd, initrd_fd, strlen(cmdline) + 1,
+			      cmdline, 0);
+
+	close(initrd_fd);
+	close(kernel_fd);
+
+	return err;
+}
+
+static int run_test(int stage)
+{
+	char stage_arg[32];
+	int status;
+	pid_t pid;
+
+	snprintf(stage_arg, sizeof(stage_arg), "%d", stage);
+
+	pid = fork();
+	if (pid < 0)
+		return -1;
+
+	if (!pid) {
+		char *const argv[] = {TEST_BINARY, "-s", stage_arg, NULL};
+
+		execve(TEST_BINARY, argv, NULL);
+		fprintf(stderr, "INIT: execve failed\n");
+		_exit(1);
+	}
+
+	waitpid(pid, &status, 0);
+
+	return (WIFEXITED(status) && WEXITSTATUS(status) == 0) ? 0 : -1;
+}
+
+static int get_current_stage(void)
+{
+	char cmdline[COMMAND_LINE_SIZE];
+	ssize_t len;
+	int fd;
+
+	fd = open("/proc/cmdline", O_RDONLY);
+	if (fd < 0)
+		return -1;
+
+	len = read(fd, cmdline, sizeof(cmdline) - 1);
+	close(fd);
+
+	if (len < 0)
+		return -1;
+
+	cmdline[len] = 0;
+
+	return strstr(cmdline, "luo_stage=2") ? 2 : 1;
+}
+
+int main(int argc, char *argv[])
+{
+	int current_stage;
+	int err;
+
+	if (mount_filesystems())
+		goto err_reboot;
+
+	current_stage = get_current_stage();
+	if (current_stage < 0) {
+		fprintf(stderr, "INIT: Failed to read cmdline");
+		goto err_reboot;
+	}
+
+	printf("INIT: Starting Stage %d\n", current_stage);
+
+	if (current_stage == 1 && kexec_load()) {
+		fprintf(stderr, "INIT: Failed to load kexec kernel\n");
+		goto err_reboot;
+	}
+
+	if (run_test(current_stage)) {
+		fprintf(stderr, "INIT: Test binary returned failure\n");
+		goto err_reboot;
+	}
+
+	printf("INIT: Stage %d completed successfully.\n", current_stage);
+	reboot(current_stage == 1 ? RB_KEXEC : RB_AUTOBOOT);
+
+	return 0;
+
+err_reboot:
+	reboot(RB_AUTOBOOT);
+
+	return -1;
+}
diff --git a/tools/testing/selftests/liveupdate/luo_test.sh b/tools/testing/selftests/liveupdate/luo_test.sh
new file mode 100755
index 000000000000..1520711b1d35
--- /dev/null
+++ b/tools/testing/selftests/liveupdate/luo_test.sh
@@ -0,0 +1,276 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+set -ue
+
+CROSS_COMPILE="${CROSS_COMPILE:-""}"
+
+test_dir=$(realpath "$(dirname "$0")")
+kernel_dir=$(realpath "$test_dir/../../../..")
+
+workspace_dir=""
+headers_dir=""
+initrd=""
+KEEP_WORKSPACE=0
+
+source "$test_dir/../kselftest/ktap_helpers.sh"
+
+function get_arch_conf() {
+	local arch=$1
+	if [[ "$arch" == "arm64" ]]; then
+		QEMU_CMD="qemu-system-aarch64 -M virt -cpu max"
+		KERNEL_IMAGE="Image"
+		KERNEL_CMDLINE="console=ttyAMA0"
+	elif [[ "$arch" == "x86" ]]; then
+		QEMU_CMD="qemu-system-x86_64"
+		KERNEL_IMAGE="bzImage"
+		KERNEL_CMDLINE="console=ttyS0"
+	else
+		echo "Unsupported architecture: $arch"
+		exit 1
+	fi
+}
+
+function usage() {
+	cat <<EOF
+$0 [-d build_dir] [-j jobs] [-t target_arch] [-T test_name] [-w workspace_dir] [-k] [-h]
+Options:
+	-d)	path to the kernel build directory (default: .luo_test_build.<arch>)
+	-j)	number of jobs for compilation
+	-t)	run test for target_arch (aarch64, x86_64)
+	-T)	test name to run (default: luo_kexec_simple)
+	-w)	custom workspace directory (default: creates temp dir)
+	-k)	keep workspace directory after successful test
+	-h)	display this help
+EOF
+}
+
+function cleanup() {
+	local exit_code=$?
+
+	if [ -z "$workspace_dir" ]; then
+		ktap_finished
+		return
+	fi
+
+	if [ $exit_code -ne 0 ]; then
+		echo "# Test failed (exit code $exit_code)."
+		echo "# Workspace preserved at: $workspace_dir"
+	elif [ "$KEEP_WORKSPACE" -eq 1 ]; then
+		echo "# Workspace preserved (user request) at: $workspace_dir"
+	else
+		rm -fr "$workspace_dir"
+	fi
+	ktap_print_totals
+
+	exit $exit_code
+}
+trap cleanup EXIT
+
+function skip() {
+	local msg=${1:-""}
+	ktap_test_skip "$msg"
+	exit "$KSFT_SKIP"
+}
+
+function fail() {
+	local msg=${1:-""}
+	ktap_test_fail "$msg"
+	exit "$KSFT_FAIL"
+}
+
+function detect_cross_compile() {
+	local target=$1
+	local host=$(uname -m)
+
+	[[ "$host" == "arm64" ]] && host="aarch64"
+	[[ "$target" == "arm64" ]] && target="aarch64"
+
+	if [[ "$host" == "$target" ]]; then
+		CROSS_COMPILE=""
+		return
+	fi
+
+	if [[ -n "$CROSS_COMPILE" ]]; then
+		return
+	fi
+
+	local candidate=""
+	case "$target" in
+		aarch64) candidate="aarch64-linux-gnu-" ;;
+		x86_64)  candidate="x86_64-linux-gnu-" ;;
+		*)       skip "Auto-detection for target '$target' not supported. Please set CROSS_COMPILE manually." ;;
+	esac
+
+	if command -v "${candidate}gcc" &> /dev/null; then
+		CROSS_COMPILE="$candidate"
+	else
+		skip "Compiler '${candidate}gcc' not found. Please install it (e.g., 'apt install gcc-aarch64-linux-gnu') or set CROSS_COMPILE."
+	fi
+}
+
+function build_kernel() {
+	local build_dir=$1
+	local make_cmd=$2
+	local kimage=$3
+	local target_arch=$4
+
+	local kconfig="$build_dir/.config"
+	local common_conf="$test_dir/config"
+	local arch_conf="$test_dir/config.$target_arch"
+
+	echo "# Building kernel in: $build_dir"
+
+	"$kernel_dir/scripts/kconfig/merge_config.sh" \
+		-Q -m -O "$build_dir" "$common_conf" "$arch_conf" >> /dev/null
+	cat $kconfig
+
+	$make_cmd olddefconfig
+	$make_cmd "$kimage"
+	$make_cmd headers_install INSTALL_HDR_PATH="$headers_dir"
+}
+
+function mkinitrd() {
+	local build_dir=$1
+	local kernel_path=$2
+	local test_name=$3
+
+	# Compile the test binary and the init process
+	"$CROSS_COMPILE"gcc -static -O2 -nostdinc -nostdlib \
+		-I "$headers_dir/include" \
+		-I "$kernel_dir/tools/include/nolibc" \
+		-I "$test_dir" \
+		-o "$workspace_dir/test_binary" \
+		"$test_dir/$test_name.c" "$test_dir/luo_test_utils.c"
+
+	"$CROSS_COMPILE"gcc -s -static -Os -nostdinc -nostdlib		\
+			-fno-asynchronous-unwind-tables -fno-ident	\
+			-fno-stack-protector				\
+			-I "$headers_dir/include"			\
+			-I "$kernel_dir/tools/include/nolibc"		\
+			-o "$workspace_dir/init" "$test_dir/init.c"
+
+	cat > "$workspace_dir/cpio_list_inner" <<EOF
+dir /dev 0755 0 0
+dir /proc 0755 0 0
+dir /debugfs 0755 0 0
+nod /dev/console 0600 0 0 c 5 1
+file /init $workspace_dir/init 0755 0 0
+file /test_binary $workspace_dir/test_binary 0755 0 0
+EOF
+
+	# Generate inner_initrd.cpio
+	"$build_dir/usr/gen_init_cpio" "$workspace_dir/cpio_list_inner" > "$workspace_dir/inner_initrd.cpio"
+
+	cat > "$workspace_dir/cpio_list" <<EOF
+dir /dev 0755 0 0
+dir /proc 0755 0 0
+dir /debugfs 0755 0 0
+nod /dev/console 0600 0 0 c 5 1
+file /init $workspace_dir/init 0755 0 0
+file /kernel $kernel_path 0644 0 0
+file /test_binary $workspace_dir/test_binary 0755 0 0
+file /initrd.img $workspace_dir/inner_initrd.cpio 0644 0 0
+EOF
+
+	# Generate the final initrd
+	"$build_dir/usr/gen_init_cpio" "$workspace_dir/cpio_list" > "$initrd"
+	local size=$(du -h "$initrd" | cut -f1)
+}
+
+function run_qemu() {
+	local qemu_cmd=$1
+	local cmdline=$2
+	local kernel_path=$3
+	local serial="$workspace_dir/qemu.serial"
+
+	cmdline="$cmdline liveupdate=on panic=-1"
+
+	echo "# Serial Log: $serial"
+	timeout 30s $qemu_cmd -m 1G -smp 2 -no-reboot -nographic -nodefaults	\
+		  -accel tcg -accel hvf -accel kvm				\
+		  -serial file:"$serial"					\
+		  -append "$cmdline"						\
+		  -kernel "$kernel_path"					\
+		  -initrd "$initrd"
+
+	local ret=$?
+
+	if [ $ret -eq 124 ]; then
+		fail "QEMU timed out"
+	fi
+
+	grep "TEST PASSED" "$serial" &> /dev/null || fail "Liveupdate failed. Check $serial for details."
+}
+
+function target_to_arch() {
+	local target=$1
+	case $target in
+	     aarch64) echo "arm64" ;;
+	     x86_64) echo "x86" ;;
+	     *) skip "architecture $target is not supported"
+	esac
+}
+
+function main() {
+	local build_dir=""
+	local jobs=$(nproc)
+	local target="$(uname -m)"
+	local test_name="luo_kexec_simple"
+	local workspace_arg=""
+
+	set -o errtrace
+	trap fail ERR
+
+	while getopts 'hd:j:t:T:w:k' opt; do
+		case $opt in
+		d) build_dir="$OPTARG" ;;
+		j) jobs="$OPTARG" ;;
+		t) target="$OPTARG" ;;
+		T) test_name="$OPTARG" ;;
+		w) workspace_arg="$OPTARG" ;;
+		k) KEEP_WORKSPACE=1 ;;
+		h) usage; exit 0 ;;
+		*) echo "Unknown argument $opt"; usage; exit 1 ;;
+		esac
+	done
+
+	ktap_print_header
+	ktap_set_plan 1
+
+	if [ -n "$workspace_arg" ]; then
+		workspace_dir="$(realpath -m "$workspace_arg")"
+		mkdir -p "$workspace_dir"
+	else
+		workspace_dir=$(mktemp -d /tmp/luo-test.XXXXXXXX)
+	fi
+
+	echo "# Workspace created at: $workspace_dir"
+	headers_dir="$workspace_dir/usr"
+	initrd="$workspace_dir/initrd.cpio"
+
+	detect_cross_compile "$target"
+
+	local arch=$(target_to_arch "$target")
+
+	if [ -z "$build_dir" ]; then
+		build_dir="$kernel_dir/.luo_test_build.$arch"
+	fi
+
+	mkdir -p "$build_dir"
+	build_dir=$(realpath "$build_dir")
+	get_arch_conf "$arch"
+
+	local make_cmd="make -s ARCH=$arch CROSS_COMPILE=$CROSS_COMPILE -j$jobs"
+	local make_cmd_build="$make_cmd -C $kernel_dir O=$build_dir"
+
+	build_kernel "$build_dir" "$make_cmd_build" "$KERNEL_IMAGE" "$target"
+
+	local final_kernel="$build_dir/arch/$arch/boot/$KERNEL_IMAGE"
+	mkinitrd "$build_dir" "$final_kernel" "$test_name"
+
+	run_qemu "$QEMU_CMD" "$KERNEL_CMDLINE" "$final_kernel"
+	ktap_test_pass "$test_name succeeded"
+}
+
+main "$@"
diff --git a/tools/testing/selftests/liveupdate/luo_test_utils.c b/tools/testing/selftests/liveupdate/luo_test_utils.c
index 3c8721c505df..100dc0f69f37 100644
--- a/tools/testing/selftests/liveupdate/luo_test_utils.c
+++ b/tools/testing/selftests/liveupdate/luo_test_utils.c
@@ -20,9 +20,14 @@
 #include <sys/stat.h>
 #include <errno.h>
 #include <stdarg.h>
+#include <linux/unistd.h>
 
 #include "luo_test_utils.h"
 
+#ifdef NOLIBC
+#include <sys.h>
+#endif
+
 int luo_open_device(void)
 {
 	return open(LUO_DEVICE, O_RDWR);
@@ -32,8 +37,8 @@ int luo_create_session(int luo_fd, const char *name)
 {
 	struct liveupdate_ioctl_create_session arg = { .size = sizeof(arg) };
 
-	snprintf((char *)arg.name, LIVEUPDATE_SESSION_NAME_LENGTH, "%.*s",
-		 LIVEUPDATE_SESSION_NAME_LENGTH - 1, name);
+	strncpy((char *)arg.name, name, LIVEUPDATE_SESSION_NAME_LENGTH);
+	arg.name[LIVEUPDATE_SESSION_NAME_LENGTH - 1] = '\0';
 
 	if (ioctl(luo_fd, LIVEUPDATE_IOCTL_CREATE_SESSION, &arg) < 0)
 		return -errno;
@@ -45,8 +50,8 @@ int luo_retrieve_session(int luo_fd, const char *name)
 {
 	struct liveupdate_ioctl_retrieve_session arg = { .size = sizeof(arg) };
 
-	snprintf((char *)arg.name, LIVEUPDATE_SESSION_NAME_LENGTH, "%.*s",
-		 LIVEUPDATE_SESSION_NAME_LENGTH - 1, name);
+	strncpy((char *)arg.name, name, LIVEUPDATE_SESSION_NAME_LENGTH);
+	arg.name[LIVEUPDATE_SESSION_NAME_LENGTH - 1] = '\0';
 
 	if (ioctl(luo_fd, LIVEUPDATE_IOCTL_RETRIEVE_SESSION, &arg) < 0)
 		return -errno;
@@ -57,7 +62,7 @@ int luo_retrieve_session(int luo_fd, const char *name)
 int create_and_preserve_memfd(int session_fd, int token, const char *data)
 {
 	struct liveupdate_session_preserve_fd arg = { .size = sizeof(arg) };
-	long page_size = sysconf(_SC_PAGE_SIZE);
+	long page_size = getpagesize();
 	void *map = MAP_FAILED;
 	int mfd = -1, ret = -1;
 
@@ -93,7 +98,7 @@ int restore_and_verify_memfd(int session_fd, int token,
 			     const char *expected_data)
 {
 	struct liveupdate_session_retrieve_fd arg = { .size = sizeof(arg) };
-	long page_size = sysconf(_SC_PAGE_SIZE);
+	long page_size = getpagesize();
 	void *map = MAP_FAILED;
 	int mfd = -1, ret = -1;
 
@@ -204,16 +209,11 @@ void daemonize_and_wait(void)
 
 static int parse_stage_args(int argc, char *argv[])
 {
-	static struct option long_options[] = {
-		{"stage", required_argument, 0, 's'},
-		{0, 0, 0, 0}
-	};
-	int option_index = 0;
 	int stage = 1;
 	int opt;
 
 	optind = 1;
-	while ((opt = getopt_long(argc, argv, "s:", long_options, &option_index)) != -1) {
+	while ((opt = getopt(argc, argv, "s:")) != -1) {
 		switch (opt) {
 		case 's':
 			stage = atoi(optarg);
@@ -224,6 +224,7 @@ static int parse_stage_args(int argc, char *argv[])
 			fail_exit("Unknown argument");
 		}
 	}
+
 	return stage;
 }
 
@@ -251,7 +252,7 @@ int luo_test(int argc, char *argv[],
 		fail_exit("Failed to check for state session");
 
 	if (target_stage != detected_stage) {
-		ksft_exit_fail_msg("Stage mismatch Requested --stage %d, but system is in stage %d.\n"
+		ksft_exit_fail_msg("Stage mismatch Requested stage %d, but system is in stage %d.\n"
 				   "(State session %s: %s)\n",
 				   target_stage, detected_stage, state_session_name,
 				   (detected_stage == 2) ? "EXISTS" : "MISSING");
diff --git a/tools/testing/selftests/liveupdate/run.sh b/tools/testing/selftests/liveupdate/run.sh
new file mode 100755
index 000000000000..5637668ef7b6
--- /dev/null
+++ b/tools/testing/selftests/liveupdate/run.sh
@@ -0,0 +1,63 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+SCRIPT_DIR=$(dirname "$(realpath "$0")")
+OUTPUT_DIR="$SCRIPT_DIR/results_$(date +%Y%m%d_%H%M%S)"
+TEST_RUNNER="$SCRIPT_DIR/luo_test.sh"
+
+TARGETS=("x86_64" "aarch64")
+
+GREEN='\033[0;32m'
+RED='\033[0;31m'
+YELLOW='\033[1;33m'
+NC='\033[0m'
+
+PASSED=()
+FAILED=()
+SKIPPED=()
+
+mkdir -p "$OUTPUT_DIR"
+
+TEST_NAMES=(
+    "luo_kexec_simple"
+    "luo_multi_session"
+)
+
+for arch in "${TARGETS[@]}"; do
+    for test_name in "${TEST_NAMES[@]}"; do
+        log_file="$OUTPUT_DIR/${arch}_${test_name}.log"
+        echo -n "  -> $arch $test_name ... "
+
+        if "$TEST_RUNNER" -t "$arch" -T "$test_name" > "$log_file" 2>&1; then
+            echo -e "${GREEN}PASS${NC}"
+            PASSED+=("${arch}:${test_name}")
+        else
+            exit_code=$?
+            if [ $exit_code -eq 4 ]; then
+                echo -e "${YELLOW}SKIP${NC}"
+                SKIPPED+=("${arch}:${test_name}")
+            else
+                echo -e "${RED}FAIL${NC}"
+                FAILED+=("${arch}:${test_name}")
+            fi
+        fi
+    done
+    echo ""
+done
+
+echo "========================================="
+echo "             TEST SUMMARY                "
+echo "========================================="
+echo -e "PASSED: ${GREEN}${#PASSED[@]}${NC}"
+echo -e "FAILED: ${RED}${#FAILED[@]}${NC}"
+for fail in "${FAILED[@]}"; do
+    echo -e "  - $fail"
+done
+echo -e "SKIPPED: ${YELLOW}${#SKIPPED[@]}${NC}"
+echo "Logs: $OUTPUT_DIR"
+
+if [ ${#FAILED[@]} -eq 0 ]; then
+    exit 0
+else
+    exit 1
+fi
-- 
2.53.0.rc2.204.g2597b5adb4-goog

Re: [PATCH v2 1/2] tools/nolibc: add ftruncate()

[Thomas Weißschuh]

Hi Jordan,

(please Cc nolibc maintainers on nolibc changes, I only saw this by
chance)

On 2026-02-05 22:23:28+0000, Jordan Richards wrote:
> ---
>  tools/include/nolibc/unistd.h | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/tools/include/nolibc/unistd.h b/tools/include/nolibc/unistd.h
> index bb5e80f3f05d..845d10f48fd0 100644
> --- a/tools/include/nolibc/unistd.h
> +++ b/tools/include/nolibc/unistd.h
> @@ -48,6 +48,17 @@ int access(const char *path, int amode)
>  	return faccessat(AT_FDCWD, path, amode, 0);
>  }
>  
> +static __attribute__((unused))
> +int sys_ftruncate(int fd, off_t length)
> +{
> +	return my_syscall2(__NR_ftruncate, fd, length);
> +}

off_t is now always 64bit on nolibc. On 32-bit architectures however
__NR_ftruncate only takes a 32bit value, leading to the wrong kind of
truncation. Use __NR_ftruncate64 instead where available.

Please also add a simple test to
tools/testing/selftests/nolibc/nolibc-test.c

> +
> +static __attribute__((unused))
> +int ftruncate(int fd, off_t length)
> +{
> +	return __sysret(sys_ftruncate(fd, length));
> +}
>  
>  static __attribute__((unused))
>  int msleep(unsigned int msecs)
> -- 
> 2.53.0.rc2.204.g2597b5adb4-goog
> 

Re: [PATCH v2 2/2] selftests/liveupdate: add end to end test infrastructure and scripts

[Thomas Weißschuh]

On 2026-02-05 22:23:29+0000, Jordan Richards wrote:
> From: Pasha Tatashin <pasha.tatashin@soleen.com>

(...)

> diff --git a/tools/testing/selftests/liveupdate/luo_test_utils.c b/tools/testing/selftests/liveupdate/luo_test_utils.c
> index 3c8721c505df..100dc0f69f37 100644
> --- a/tools/testing/selftests/liveupdate/luo_test_utils.c
> +++ b/tools/testing/selftests/liveupdate/luo_test_utils.c
> @@ -20,9 +20,14 @@
>  #include <sys/stat.h>
>  #include <errno.h>
>  #include <stdarg.h>
> +#include <linux/unistd.h>
>  
>  #include "luo_test_utils.h"
>  
> +#ifdef NOLIBC
> +#include <sys.h>
> +#endif

This should not be necessary.
I am actively trying to get rid of the checks for the NOLIBC macro.

> +
>  int luo_open_device(void)
>  {
>  	return open(LUO_DEVICE, O_RDWR);

(...)

> @@ -45,8 +50,8 @@ int luo_retrieve_session(int luo_fd, const char *name)
>  {
>  	struct liveupdate_ioctl_retrieve_session arg = { .size = sizeof(arg) };
>  
> -	snprintf((char *)arg.name, LIVEUPDATE_SESSION_NAME_LENGTH, "%.*s",
> -		 LIVEUPDATE_SESSION_NAME_LENGTH - 1, name);
> +	strncpy((char *)arg.name, name, LIVEUPDATE_SESSION_NAME_LENGTH);
> +	arg.name[LIVEUPDATE_SESSION_NAME_LENGTH - 1] = '\0';

FWIW we are currently working on "%.*s" support.

>  
>  	if (ioctl(luo_fd, LIVEUPDATE_IOCTL_RETRIEVE_SESSION, &arg) < 0)
>  		return -errno;

(...)

Re: [PATCH v2 2/2] selftests/liveupdate: add end to end test infrastructure and scripts

[Mike Rapoport]

Hi Jordan,

On Thu, Feb 05, 2026 at 10:23:29PM +0000, Jordan Richards wrote:
> From: Pasha Tatashin <pasha.tatashin@soleen.com>
> 
> Add the end to end testing infrastructure required to verify the
> liveupdate feature. This includes a custom init process, a test
> orchestration script, and a batch runner.
> 
> The framework consists of:
> 
> init.c:
> A lightweight init process that manages the kexec lifecycle.
> It mounts necessary filesystems, determines the current execution
> stage (1 or 2) via the kernel command line, and handles the
> kexec_file_load() sequence to transition between kernels.
> 
> luo_test.sh:
> The primary KTAP-compliant test driver. It handles:
> - Kernel configuration merging and building.
> - Cross-compilation detection for x86_64 and arm64.
> - Generation of the initrd containing the test binary and init.
> - QEMU execution with automatic accelerator detection (KVM, HVF,
>  or TCG).
> 
> run.sh:
> A wrapper script to discover and execute all `luo_*.c`
> tests across supported architectures, providing a summary of
> pass/fail/skip results.
> 
> Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>

I think you also need 
Co-developed-by: Jordan Richards <jordanrichards@google.com>

> Signed-off-by: Jordan Richards <jordanrichards@google.com>

With nolibc fixes Thomas requested:

Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>

-- 
Sincerely yours,
Mike.

Re: [PATCH v2 2/2] selftests/liveupdate: add end to end test infrastructure and scripts

[Jordan Richards]

>> +#ifdef NOLIBC
>> +#include <sys.h>
>> +#endif
>
> This should not be necessary.
> I am actively trying to get rid of the checks for the NOLIBC macro.

Oops, that's no longer used directly. Will remove in v3.

Re: [PATCH v2 2/2] selftests/liveupdate: add end to end test infrastructure and scripts

[Pratyush Yadav]

On Sun, Feb 08 2026, Mike Rapoport wrote:

> Hi Jordan,
>
> On Thu, Feb 05, 2026 at 10:23:29PM +0000, Jordan Richards wrote:
>> From: Pasha Tatashin <pasha.tatashin@soleen.com>
>> 
>> Add the end to end testing infrastructure required to verify the
>> liveupdate feature. This includes a custom init process, a test
>> orchestration script, and a batch runner.
>> 
>> The framework consists of:
>> 
>> init.c:
>> A lightweight init process that manages the kexec lifecycle.
>> It mounts necessary filesystems, determines the current execution
>> stage (1 or 2) via the kernel command line, and handles the
>> kexec_file_load() sequence to transition between kernels.
>> 
>> luo_test.sh:
>> The primary KTAP-compliant test driver. It handles:
>> - Kernel configuration merging and building.
>> - Cross-compilation detection for x86_64 and arm64.
>> - Generation of the initrd containing the test binary and init.
>> - QEMU execution with automatic accelerator detection (KVM, HVF,
>>  or TCG).
>> 
>> run.sh:
>> A wrapper script to discover and execute all `luo_*.c`
>> tests across supported architectures, providing a summary of
>> pass/fail/skip results.
>> 
>> Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
>
> I think you also need 
> Co-developed-by: Jordan Richards <jordanrichards@google.com>
>
>> Signed-off-by: Jordan Richards <jordanrichards@google.com>
>
> With nolibc fixes Thomas requested:
>
> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>

I didn't look too closely, but at a quick skim, LGTM.

Acked-by: Pratyush Yadav (Google) <pratyush@kernel.org>

-- 
Regards,
Pratyush Yadav