From b9a4530e542874486f74f4f91933fd0c2cab2dec Mon Sep 17 00:00:00 2001
From: Bananymous <bananymousosq@gmail.com>
Date: Mon, 16 Jan 2023 21:50:50 +0200
Subject: [PATCH] Kernel: Kernel::Panic now dumps stacktrace to com1

---
 kernel/arch/i386/boot.S       |  1 +
 kernel/include/kernel/Panic.h | 19 +++++++++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/kernel/arch/i386/boot.S b/kernel/arch/i386/boot.S
index 501647d3..efe1c65f 100644
--- a/kernel/arch/i386/boot.S
+++ b/kernel/arch/i386/boot.S
@@ -117,6 +117,7 @@ _start:
 	call _init
 
 	# call to the kernel itself
+	xorl %ebp, %ebp
 	call kernel_main
 
 system_halt:
diff --git a/kernel/include/kernel/Panic.h b/kernel/include/kernel/Panic.h
index 434e964e..402b07db 100644
--- a/kernel/include/kernel/Panic.h
+++ b/kernel/include/kernel/Panic.h
@@ -9,12 +9,31 @@
 namespace Kernel
 {
 
+	static void dump_stacktrace()
+	{
+		struct stackframe
+		{
+			stackframe* ebp;
+			uint32_t eip;
+		};
+
+		stackframe* frame;
+		asm volatile("movl %%ebp, %0" : "=r"(frame));
+		BAN::Formatter::println(Serial::serial_putc, "\e[36mStack trace:");
+		while (frame)
+		{
+			BAN::Formatter::println(Serial::serial_putc, "    0x{8H}", frame->eip);
+			frame = frame->ebp;
+		}
+	}
+
 	template<typename... Args>
 	__attribute__((__noreturn__))
 	static void PanicImpl(const char* file, int line, const char* message, Args... args)
 	{
 		derrorln("Kernel panic at {}:{}", file, line);
 		derrorln(message, args...);
+		dump_stacktrace();
 		if (TTY::IsInitialized())
 		{
 			kprint("\e[31mKernel panic at {}:{}\n", file, line);