Make VirtioConsolesPrinter heapless

kernel/comps/console/src/lib.rs

@@ -13,7 +13,7 @@ use core::any::Any;
 use component::{init_component, ComponentInitError};
 use ostd::{
     mm::{Infallible, VmReader},
-    sync::SpinLock,
+    sync::{LocalIrqDisabled, SpinLock, SpinLockGuard},
 };
 use spin::Once;
 
@@ -52,6 +52,16 @@ pub fn all_devices() -> Vec<(String, Arc<dyn AnyConsoleDevice>)> {
         .collect()
 }
 
+pub fn all_devices_lock<'a>(
+) -> SpinLockGuard<'a, BTreeMap<String, Arc<dyn AnyConsoleDevice>>, LocalIrqDisabled> {
+    COMPONENT
+        .get()
+        .unwrap()
+        .console_device_table
+        .disable_irq()
+        .lock()
+}
+
 static COMPONENT: Once<Component> = Once::new();
 
 #[init_component]

kernel/comps/logger/src/console.rs

@@ -11,7 +11,11 @@ struct VirtioConsolesPrinter;
 
 impl Write for VirtioConsolesPrinter {
     fn write_str(&mut self, s: &str) -> core::fmt::Result {
-        for (_, device) in aster_console::all_devices() {
+        // We must call `all_devices_lock` instead of `all_devices` here, as `all_devices` invokes
+        // the clone method of String and Arc, which may lead to a deadlock when there is low memory
+        // in the heap (The heap allocator will log a message when memory is low.).
+        let devices = aster_console::all_devices_lock();
+        for (_, device) in devices.iter() {
             device.send(s.as_bytes());
         }
         Ok(())