update according to Colin's comment

Author: HuijingHei

src/blockdev.rs

@@ -6,16 +6,10 @@ use anyhow::{bail, Context, Result};
 use bootc_blockdev::PartitionTable;
 use fn_error_context::context;
 
-static PARENT_DEVICES: OnceLock<Vec<String>> = OnceLock::new();
-
-// Initialize once
-pub fn init_parent_devices(strings: Vec<String>) {
-    PARENT_DEVICES.set(strings).expect("Already initialized");
-}
-
-// Read many times (lock-free)
-pub fn get_parent_devices() -> &'static [String] {
-    PARENT_DEVICES.get().expect("Not initialized")
+/// Get parent devices
+pub fn get_or_init_parent_devices(devices: Option<Vec<String>>) -> &'static [String] {
+    static PARENT_DEVICES: OnceLock<Vec<String>> = OnceLock::new();
+    PARENT_DEVICES.get_or_init(|| devices.unwrap())
 }
 
 #[context("get parent devices from mount point boot")]
@@ -68,7 +62,7 @@ pub fn get_esp_partition(device: &str) -> Result<Option<String>> {
 #[allow(dead_code)]
 pub fn find_colocated_esps() -> Result<Vec<String>> {
     // first, get the parent device
-    let devices = get_parent_devices();
+    let devices = get_or_init_parent_devices(None);
 
     // now, look for all ESPs on those devices
     let mut esps = Vec::new();
@@ -99,7 +93,7 @@ pub fn get_bios_boot_partition(device: &str) -> Result<Option<String>> {
 #[allow(dead_code)]
 pub fn find_colocated_bios_boot() -> Result<Vec<String>> {
     // first, get the parent device
-    let devices = get_parent_devices();
+    let devices = get_or_init_parent_devices(None);
 
     // now, look for all bios_boot parts on those devices
     let mut bios_boots = Vec::new();

src/cli/bootupctl.rs

@@ -3,7 +3,6 @@ use anyhow::{Context, Result};
 use clap::Parser;
 use log::LevelFilter;
 
-use std::os::unix::io::AsRawFd;
 use std::os::unix::process::CommandExt;
 use std::process::{Command, Stdio};
 
@@ -220,11 +219,8 @@ fn run_status_in_container(json_format: bool) -> Result<()> {
 /// Initialize parent devices to prepare the update
 fn prep_before_update() -> Result<openat::Dir> {
     let sysroot = openat::Dir::open("/").context("Opening root dir")?;
-    let dest_fd = format!("/proc/self/fd/{}", sysroot.as_raw_fd());
-    let dest_root = std::fs::read_link(dest_fd)?;
-
-    let devices = crate::blockdev::get_devices(&dest_root)
-        .with_context(|| "while looking for parent devices")?;
-    crate::blockdev::init_parent_devices(devices);
+    let devices = crate::blockdev::get_devices("/").context("get parent devices")?;
+    crate::blockdev::get_or_init_parent_devices(Some(devices));
+    crate::blockdev::get_or_init_parent_devices(None);
     Ok(sysroot)
 }