Add a very hackish /proc/PID/stack.

It walks the stack and identifies anything that looks like a kernel symbol.
This could be a lot more sophisticated.

Kernel/init.cpp

@@ -28,6 +28,7 @@
 #include "RTC.h"
 
 #define TEST_VFS
+#define KERNEL_MAP
 //#define STRESS_TEST_SPAWNING
 //#define TEST_ELF_LOADER
 //#define TEST_CRASHY_USER_PROCESSES
@@ -49,6 +50,43 @@ void banner()
     kprintf("\n");
 }
 
+static byte parseHexDigit(char nibble)
+{
+    if (nibble >= '0' && nibble <= '9')
+        return nibble - '0';
+    ASSERT(nibble >= 'a' && nibble <= 'f');
+    return 10 + (nibble - 'a');
+}
+
+static Vector<KSym>* s_ksyms;
+
+Vector<KSym>& ksyms()
+{
+    return *s_ksyms;
+}
+
+static void loadKernelMap(const ByteBuffer& buffer)
+{
+    s_ksyms = new Vector<KSym>;
+    auto* bufptr = (const char*)buffer.pointer();
+    auto* startOfName = bufptr;
+    dword address = 0;
+
+    while (bufptr < buffer.endPointer()) {
+        for (unsigned i = 0; i < 8; ++i)
+            address = (address << 4) | parseHexDigit(*(bufptr++));
+        bufptr += 3;
+        startOfName = bufptr;
+        while (*(++bufptr)) {
+            if (*bufptr == '\n') {
+                break;
+            }
+        }
+        ksyms().append({ address, String(startOfName, bufptr - startOfName) });
+        ++bufptr;
+    }
+}
+
 #ifdef TEST_CRASHY_USER_PROCESSES
 static void user_main() NORETURN;
 static void user_main()
@@ -108,6 +146,19 @@ static void init_stage2()
 
     vfs->mountRoot(e2fs.copyRef());
 
+#ifdef KERNEL_MAP
+    {
+        auto handle = vfs->open("/kernel.map");
+        if (!handle) {
+            kprintf("Failed to open /kernel.map\n");
+        } else {
+            auto buffer = handle->readEntireFile();
+            ASSERT(buffer);
+            loadKernelMap(buffer);
+        }
+    }
+#endif
+
     vfs->mount(ProcFileSystem::the(), "/proc");
 
 #endif