commit - 85231712942b13d915c19f9d168624a0516a8824
commit + 2257f59c3fcad7f544c256ad2c936495981a99cd
blob - e39e7b4977c6690f473b25fc45c192c342f30807
blob + 3ce79dca00c2b66d52b410d3bf6fec769678db60
--- kernel/log/early_console.c
+++ kernel/log/early_console.c
@@ -4,6 +4,7 @@
 #include <stdbool.h>
 #include "early_console.h"
 #include "log/serial.h"
+#include "sync/spinlock.h"
 
 #define EARLY_CONSOLE_BUFFER_SIZE 16384
 
@@ -12,6 +13,7 @@ static size_t early_console_head = 0;
 static size_t early_console_tail = 0;
 static int early_console_wrapping = 0;
 static bool early_console_serial_enabled = true;  /* Disabled once console service ready */
+static spinlock_t early_console_lock = SPINLOCK_INIT;
 
 void
 early_console_write(const char *data, size_t len)
@@ -19,6 +21,9 @@ early_console_write(const char *data, size_t len)
 	if (data == NULL || len == 0)
 		return;
 
+	/* Lock to prevent concurrent writes from corrupting output */
+	spinlock_lock(&early_console_lock);
+
 	/* Write to ring buffer */
 	for (size_t i = 0; i < len; i++) {
 		early_console_ring[early_console_head] = data[i];
@@ -35,6 +40,8 @@ early_console_write(const char *data, size_t len)
 	/* Also write immediately to serial for real-time visibility (if still enabled) */
 	if (early_console_serial_enabled)
 		serial_write(data, len);
+
+	spinlock_unlock(&early_console_lock);
 }
 
 size_t