wrote a basic bootloader

scripts/build_stage1.sh

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+#!/bin/bash
+set -e
+
+# Set root directory
+cd "$(dirname "$0")/.."
+
+# Create build directory if it doesn't exist
+mkdir -p build/bios
+
+# Assemble stage1
+nasm -f elf32 boot/bios/stage1/stage1.s -o build/bios/stage1.o
+
+# Link to binary
+ld -m elf_i386 -T boot/bios/stage1/stage1.ld build/bios/stage1.o -o build/bios/stage1.bin
+
+# Verify size
+size=$(wc -c < build/bios/stage1.bin)
+if [ "$size" -gt 446 ]; then
+    echo "Error: stage1.bin is larger than 446 bytes ($size bytes)"
+    exit 1
+fi
+
+echo "Successfully built stage1.bin ($size bytes)"

scripts/build_stage2.sh

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+#!/bin/bash
+set -e
+
+# Set root directory
+cd "$(dirname "$0")/.."
+
+# Create build directory if it doesn't exist
+mkdir -p build/bios
+
+# Compile C code
+gcc -m32 -ffreestanding -fno-pie -fno-stack-protector -nostdlib -nodefaultlibs \
+    -Wall -Wextra -O2 -c boot/bios/stage2/stage2.c -o build/bios/stage2.o
+
+# Assemble boot code
+nasm -f elf32 boot/bios/stage2/boot.s -o build/bios/boot.o
+
+# Link to binary
+ld -m elf_i386 -T boot/bios/stage2/stage2.ld \
+    build/bios/boot.o \
+    build/bios/stage2.o \
+    -o build/bios/stage2.bin
+
+# Verify size (stage2 can be multiple sectors, but let's warn if it's too large)
+size=$(wc -c < build/bios/stage2.bin)
+if [ "$size" -gt 32768 ]; then    # 64 sectors (32KB) should be plenty
+    echo "Warning: stage2.bin is larger than 32KB ($size bytes)"
+fi
+
+echo "Successfully built stage2.bin ($size bytes)"

scripts/create_disk.sh

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+#!/bin/bash
+
+set -e
+
+# Size in MB
+DISK_SIZE=64
+ESP_SIZE=100  # Size of EFI System Partition in sectors (100 sectors = ~50KB, enough for our bootloader)
+
+# Create build directory if it doesn't exist
+mkdir -p build/bios
+
+# Build stage 1/2 bootloader
+./scripts/build_stage1.sh
+./scripts/build_stage2.sh
+
+# Create an empty disk image
+dd if=/dev/zero of=disk.img bs=1M count=$DISK_SIZE
+
+# Create a partition table
+(
+echo o # Create a new empty DOS partition table
+echo n # Add a new partition (EFI System Partition)
+echo p # Primary partition
+echo 1 # Partition number 1
+echo 2048 # First sector (leaving room for bootloader)
+echo +${ESP_SIZE} # Size in sectors
+echo t # Change partition type
+echo ef # EFI System Partition type
+
+echo n # Add a new partition (Main partition)
+echo p # Primary partition
+echo 2 # Partition number 2
+echo # Default first sector (right after ESP)
+echo # Use rest of disk
+echo t # Change partition type
+echo 2 # Select second partition
+echo 0c # FAT32 LBA type
+echo a # Make bootable
+echo 2 # Select second partition
+echo w # Write changes
+) | fdisk disk.img > /dev/null 2>&1
+
+# Copy bootloader to disk image
+# First stage (MBR)
+dd if=build/bios/stage1.bin of=disk.img conv=notrunc bs=446 count=1
+
+# Second stage (right after MBR)
+dd if=build/bios/stage2.bin of=disk.img conv=notrunc bs=512 seek=1
+
+# Format ESP partition
+ESP_OFFSET=$((2048 * 512))  # First partition starts at sector 2048
+mformat -i disk.img@@${ESP_OFFSET} -F -h 255 -t 1 -s 63 -c 1 ::
+
+# Format main partition
+MAIN_OFFSET=$(( (2048 + ESP_SIZE) * 512 ))  # Second partition starts after ESP
+mformat -i disk.img@@${MAIN_OFFSET} -F -h 255 -t 1 -s 63 -c 1 ::
+
+# Create EFI directory structure in ESP
+mmd -i disk.img@@${ESP_OFFSET} ::/EFI
+mmd -i disk.img@@${ESP_OFFSET} ::/EFI/BOOT
+
+# When you have the UEFI bootloader ready, uncomment this:
+# mcopy -i disk.img@@${ESP_OFFSET} boot/uefi/BOOTX64.EFI ::/EFI/BOOT/

scripts/run.sh

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+#!/bin/bash
+
+set -e
+
+# set root directory of project
+cd "$(dirname "$0")/.."
+
+# Build the bootloader
+./scripts/create_disk.sh
+
+# Default to KVM if available
+KVM_FLAGS=""
+if [ -c /dev/kvm ]; then
+    KVM_FLAGS="-enable-kvm -cpu host"
+fi
+
+# Run QEMU with appropriate flags
+qemu-system-x86_64 \
+    $KVM_FLAGS \
+    -m 4G \
+    -drive file=disk.img,format=raw \
+    -monitor stdio \
+    -no-reboot \
+    -no-shutdown \
+    -smp 4 \
+    -serial file:serial.log