add sanity check script for kernel ELF validation

Author: chrisdedman

check-kernel.sh

@@ -0,0 +1,57 @@
+#!/usr/bin/env bash
+# This file contain multiple sanity check for testing purpose of the
+# vectors table alginement and such.
+# run chmod +x ./check-kernel.sh before hand
+set -e
+
+ELF=build/kernel.elf
+
+echo "=== Running sanity checks on $ELF ==="
+
+# Check .vectors at 0x0
+if arm-none-eabi-objdump -h "$ELF" | grep -q '\.vectors.*00000000'; then
+  echo "[PASS] .vectors section is mapped at VMA 0x00000000"
+else
+  echo "[FAIL] .vectors not at 0x0!"
+fi
+
+# Check entry point is _start
+ENTRY=$(arm-none-eabi-readelf -h "$ELF" | grep 'Entry point' | awk '{print $4}' | sed 's/^0x//')
+START_ADDR=$(arm-none-eabi-nm -n "$ELF" | grep " T _start" | awk '{print $1}')
+if [ $((16#$ENTRY)) -eq $((16#$START_ADDR)) ]; then
+  echo "[PASS] Entry point matches _start (0x$ENTRY)"
+else
+  echo "[FAIL] Entry point mismatch: entry=0x$ENTRY, _start=0x$START_ADDR"
+fi
+
+# Check vector table branches correctly
+DISASM=$(arm-none-eabi-objdump -d -j .vectors "$ELF")
+
+if echo "$DISASM" | grep -q "b.*<_start>"; then
+  echo "[PASS] Reset vector branches to _start"
+else
+  echo "[FAIL] Reset vector does not branch to _start!"
+fi
+
+if echo "$DISASM" | grep -q "b.*<irq_entry>"; then
+  echo "[PASS] IRQ vector branches to irq_entry"
+else
+  echo "[FAIL] IRQ vector does not branch to irq_entry!"
+fi
+
+# Check that irq_entry symbol exists
+if arm-none-eabi-nm -n "$ELF" | grep -q " T irq_entry"; then
+  echo "[PASS] irq_entry symbol is defined"
+else
+  echo "[FAIL] irq_entry missing!"
+fi
+
+# Check BSS symbols exist
+if arm-none-eabi-nm -n "$ELF" | grep -q "__bss_start" && \
+   arm-none-eabi-nm -n "$ELF" | grep -q "__bss_end"; then
+  echo "[PASS] __bss_start and __bss_end are defined"
+else
+  echo "[FAIL] Missing __bss_start/__bss_end!"
+fi
+
+echo "=== Checks complete ==="