kernel: Don't call x86_32 directly in the panic code.

arch/Arch.h

@@ -21,3 +21,9 @@ TimeStamp arch_get_time();
 __no_return void arch_reboot();
 
 __no_return void arch_shutdown();
+
+void arch_panic_dump();
+
+void arch_dump_stack_frame(void *stackframe);
+
+void arch_backtrace();

arch/x86_32/Interrupts.cpp

@@ -47,33 +47,6 @@ static const char *_exception_messages[32] = {
     "Reserved",
 };
 
-void interrupts_dump_stackframe(InterruptStackFrame *stackframe)
-{
-    printf("\tCS=%04x DS=%04x ES=%04x FS=%04x GS=%04x\n", stackframe->cs, stackframe->ds, stackframe->es, stackframe->fs, stackframe->gs);
-    printf("\tEAX=%08x EBX=%08x ECX=%08x EDX=%08x\n", stackframe->eax, stackframe->ebx, stackframe->ecx, stackframe->edx);
-    printf("\tEDI=%08x ESI=%08x EBP=%08x ESP=%08x\n", stackframe->edi, stackframe->esi, stackframe->ebp, stackframe->esp);
-    printf("\tINT=%08x ERR=%08x EIP=%08x FLG=%08x\n", stackframe->intno, stackframe->err, stackframe->eip, stackframe->eflags);
-
-    printf("\tCR0=%08x CR2=%08x CR3=%08x CR4=%08x\n", CR0(), CR2(), CR3(), CR4());
-}
-
-struct Stackframe
-{
-    struct Stackframe *ebp;
-    uint32_t eip;
-};
-
-void backtrace(uint32_t ebp)
-{
-    Stackframe *stackframe = reinterpret_cast<Stackframe *>(ebp);
-
-    while (stackframe)
-    {
-        stream_format(log_stream, "\t%08x\n", stackframe->eip);
-        stackframe = stackframe->ebp;
-    }
-}
-
 extern "C" uint32_t interrupts_handler(uintptr_t esp, InterruptStackFrame stackframe)
 {
     if (stackframe.intno < 32)
@@ -92,7 +65,7 @@ extern "C" uint32_t interrupts_handler(uintptr_t esp, InterruptStackFrame stackf
                          CR2());
 
             task_dump(scheduler_running());
-            backtrace(stackframe.ebp);
+            arch_dump_stack_frame(reinterpret_cast<void *>(&stackframe));
 
             task_exit(-1);
         }

arch/x86_32/x86_32.cpp

@@ -3,9 +3,11 @@
 
 #include "arch/x86/COM.h"
 #include "arch/x86_32/ACPI.h"
+#include "arch/x86_32/CPUID.h"
 #include "arch/x86_32/FPU.h"
 #include "arch/x86_32/GDT.h"
 #include "arch/x86_32/IDT.h"
+#include "arch/x86_32/Interrupts.h"
 #include "arch/x86_32/LAPIC.h"
 #include "arch/x86_32/PIC.h"
 #include "arch/x86_32/PIT.h"
@@ -129,3 +131,50 @@ __no_return void arch_shutdown()
     logger_error("Failled to shutdown: Halting!");
     system_stop();
 }
+
+void arch_panic_dump()
+{
+    cpuid_dump();
+}
+
+struct Stackframe
+{
+    struct Stackframe *ebp;
+    uint32_t eip;
+};
+
+void backtrace_internal(uint32_t ebp)
+{
+    bool empty = true;
+    Stackframe *stackframe = reinterpret_cast<Stackframe *>(ebp);
+
+    while (stackframe)
+    {
+        empty = false;
+        stream_format(log_stream, "\t%08x\n", stackframe->eip);
+        stackframe = stackframe->ebp;
+    }
+
+    if (empty)
+        stream_format(log_stream, "\t[EMPTY]\n");
+}
+
+void arch_dump_stack_frame(void *sf)
+{
+    auto stackframe = reinterpret_cast<InterruptStackFrame *>(sf);
+
+    printf("\tCS=%04x DS=%04x ES=%04x FS=%04x GS=%04x\n", stackframe->cs, stackframe->ds, stackframe->es, stackframe->fs, stackframe->gs);
+    printf("\tEAX=%08x EBX=%08x ECX=%08x EDX=%08x\n", stackframe->eax, stackframe->ebx, stackframe->ecx, stackframe->edx);
+    printf("\tEDI=%08x ESI=%08x EBP=%08x ESP=%08x\n", stackframe->edi, stackframe->esi, stackframe->ebp, stackframe->esp);
+    printf("\tINT=%08x ERR=%08x EIP=%08x FLG=%08x\n", stackframe->intno, stackframe->err, stackframe->eip, stackframe->eflags);
+
+    printf("\tCR0=%08x CR2=%08x CR3=%08x CR4=%08x\n", CR0(), CR2(), CR3(), CR4());
+
+    printf("\n\tBacktrace:\n");
+    backtrace_internal(stackframe->ebp);
+}
+
+void arch_backtrace()
+{
+    backtrace_internal(EBP());
+}

arch/x86_64/x86_64.cpp

@@ -92,3 +92,18 @@ __no_return void arch_shutdown()
 {
     ASSERT_NOT_REACHED();
 }
+
+void arch_panic_dump()
+{
+    ASSERT_NOT_REACHED();
+}
+
+void arch_dump_stack_frame(void *stackframe)
+{
+    ASSERT_NOT_REACHED();
+}
+
+void arch_backtrace()
+{
+    ASSERT_NOT_REACHED();
+}

kernel/.build.mk

@@ -37,7 +37,7 @@ KERNEL_CXXFLAGS = \
 	-fno-exceptions \
 	-ffreestanding \
 	-nostdlib \
-	-DCONFIG_KEYBOARD_LAYOUT=\""${CONFIG_KEYBOARD_LAYOUT}"\" 
+	-DCONFIG_KEYBOARD_LAYOUT=\""${CONFIG_KEYBOARD_LAYOUT}"\"
 
 OBJECTS += $(KERNEL_OBJECTS)
 
@@ -64,4 +64,4 @@ $(BUILD_DIRECTORY)/arch/%.s.o: arch/%.s
 $(KERNEL_BINARY): $(KERNEL_OBJECTS)
 	$(DIRECTORY_GUARD)
 	@echo [KERNEL] [LD] $(KERNEL_BINARY)
-	@$(CXX) $(LDFLAGS) -T arch/x86_32/link.ld -o $@ -ffreestanding $^ -nostdlib -lgcc
+	@$(CXX) $(LDFLAGS) -T arch/$(BUILD_ARCH)/link.ld -o $@ -ffreestanding $^ -nostdlib -lgcc

kernel/system/Panic.cpp

@@ -1,9 +1,6 @@
 #include <libsystem/thread/Atomic.h>
 
-/* XXX: we should not depend on X86 directly */
-#include "arch/x86_32/CPUID.h"
-#include "arch/x86_32/Interrupts.h"
-
+#include "arch/Arch.h"
 #include "kernel/graphics/EarlyConsole.h"
 #include "kernel/graphics/Font.h"
 #include "kernel/scheduling/Scheduler.h"
@@ -52,8 +49,6 @@ static const char *const witty_comments[] = {
 static bool has_panic = false;
 static bool nested_panic = false;
 
-void backtrace(uint32_t ebp);
-
 void system_panic_internal(
     __SOURCE_LOCATION__ location,
     void *stackframe,
@@ -109,25 +104,16 @@ void system_panic_internal(
         printf("\n");
     }
 
+    printf("\n\tStackframe:\n");
     if (stackframe)
     {
-        printf("\n\tContext:\n");
-        interrupts_dump_stackframe((InterruptStackFrame *)stackframe);
-
-        printf("\n\tBacktrace:\n");
-        backtrace(((InterruptStackFrame *)stackframe)->ebp);
-        printf("\n");
+        arch_dump_stack_frame(stackframe);
     }
     else
     {
-        uint32_t ebp;
-        asm("movl %%ebp,%0"
-            : "=r"(ebp)::);
-
-        printf("\n\tBacktrace:\n");
-        backtrace(ebp);
-        printf("\n");
+        arch_backtrace();
     }
+    printf("\n");
 
     memory_dump();
 
@@ -136,7 +122,7 @@ void system_panic_internal(
     if (!nested_panic)
     {
         task_dump(scheduler_running());
-        cpuid_dump();
+        arch_panic_dump();
     }
 
     printf("\n");