refactor, improve exception message

3 files changed, 75 insertions, 57 deletions

diff --git a/src/arch/amd64/idt.S b/src/arch/amd64/idt.S
index 1098057..32670c8 100644
--- a/src/arch/amd64/idt.S
+++ b/src/arch/amd64/idt.S
@@ -7,11 +7,13 @@ extern idt_pic_mouse
 extern idt_pic_eoi
 
 %macro PUSHALL 0
+    push rax
     push rbx
     push rcx
     push rdx
-    push rsi
+    push rbp
     push rdi
+    push rsi
     push r8
     push r9
     push r10
@@ -31,11 +33,13 @@ extern idt_pic_eoi
     pop r10
     pop r9
     pop r8
-    pop rdi
     pop rsi
+    pop rdi
+    pop rbp
     pop rdx
     pop rcx
     pop rbx
+    pop rax
 %endmacro
 
 ; call the exception handler with the interrupt number
diff --git a/src/arch/amd64/idt.c b/src/arch/amd64/idt.c
index 5c6261c..83b792c 100644
--- a/src/arch/amd64/idt.c
+++ b/src/arch/amd64/idt.c
@@ -73,68 +73,81 @@ void idt_init(void) {
 
 // Intel manual vol 3 ch 6.3.1
 char *EXCEPTIONS[] = {
-	"Exception 0x00 Divide Error",
-	"Exception 0x01 Debug Exception",
-	"Exception 0x02 NMI Interrupt",
-	"Exception 0x03 Breakpoint",
-	"Exception 0x04 Overflow",
-	"Exception 0x05 BOUND Range Exceeded",
-	"Exception 0x06 Invalid Opcode",
-	"Exception 0x07 Device Not Available",
-	"Exception 0x08 Double Fault",
-	"Exception 0x09 Coprocessor Segment Overrun",
-	"Exception 0x0A Invalid TSS",
-	"Exception 0x0B Segment Not Present",
-	"Exception 0x0C Stack-Segment Fault",
-	"Exception 0x0D General Protection",
-	"Exception 0x0E Page Fault",
-	"Exception 0x0F Reserved",
-	"Exception 0x10 x87 FPU Floating-Point Error",
-	"Exception 0x11 Alignment Check",
-	"Exception 0x12 Machine Check",
-	"Exception 0x13 SIMD Floaing-Point Exception",
-	"Exception 0x14 Virtualization Exception",
-	"Exception 0x15 Control Protection Exception",
-	"Exception 0x16 Reserved",
-	"Exception 0x17 Reserved",
-	"Exception 0x18 Reserved",
-	"Exception 0x19 Reserved",
-	"Exception 0x1A Reserved",
-	"Exception 0x1B Reserved",
-	"Exception 0x1C Reserved",
-	"Exception 0x1D Reserved",
-	"Exception 0x1E Reserved",
-	"Exception 0x1F Reserved",
+	"0x00 Division Error",
+	"0x01 Debug",
+	"0x02 NMI",
+	"0x03 Breakpoint",
+	"0x04 Overflow",
+	"0x05 BOUND Range Exceeded",
+	"0x06 Invalid Opcode",
+	"0x07 Device Not Available",
+	"0x08 Double Fault",
+	"0x09 Coprocessor Segment Overrun",
+	"0x0A Invalid TSS",
+	"0x0B Segment Not Present",
+	"0x0C Stack-Segment Fault",
+	"0x0D General Protection Fault",
+	"0x0E Page Fault",
+	"0x0F Reserved",
+	"0x10 x87 Floating-Point Error",
+	"0x11 Alignment Check",
+	"0x12 Machine Check",
+	"0x13 SIMD Floaing-Point Exception",
+	"0x14 Virtualization Exception",
+	"0x15 Control Protection Exception",
+	"0x16 Reserved",
+	"0x17 Reserved",
+	"0x18 Reserved",
+	"0x19 Reserved",
+	"0x1A Reserved",
+	"0x1B Reserved",
+	"0x1C Hypervisor Injection Exception",
+	"0x1D VMM Communication Exception",
+	"0x1E Security Exception",
+	"0x1F Reserved",
 };
 
+void idt_exception_handler(uint64_t exception, uint64_t code) {
+	// TODO don't just panic
+	char buf[24];
+	char msg[256] = "Exception ";
+
+	strcat(msg, EXCEPTIONS[exception]);
+
+	strcat(msg, "\nError code 0x");
+	ultoa(code, buf, 16);
+	strcat(msg, buf);
+
+	// page faults store the offending address in cr2
+	if(exception == 0x0E) {
+		strcat(msg, "\nPage fault address: 0x");
+		void *addr;
+		__asm__ volatile ("mov %%cr2, %0" : "=r"(addr));
+		ultoa((size_t)addr, buf, 16);
+		strcat(msg, buf);
+	}
+
+	panic(msg);
+}
+
 void idt_pic_eoi(uint8_t exception) {
 	pic_eoi(exception - PIC_REMAP_OFFSET);
 }
 
-static size_t timer = 0;
+int counter = 0;
 
 void idt_pic_timer(void) {
-	timer += 1;
-	char buf[20];
-	ltoa(timer, buf, 10);
-	serial_out_str(buf);
-	serial_out_str("\n");
-}
-
-void idt_pic_keyboard(void) {
-	serial_out_str("ps2 kbd");
+	// print a message once we know the timer works
+	// but avoid spamming the logs
+	if (counter == 3) {
+		serial_out_str("pic timer!\n");
+	}
+	if (counter <= 3) {
+		counter++;
+	}
 }
 
-void idt_pic_mouse(void) {
-	serial_out_str("ps2 mouse");
-}
+void idt_pic_keyboard(void) {}
 
-void idt_exception_handler(uint64_t exception, uint64_t code) {
-	// TODO don't just panic
-	char buf[80];
-	char *end = strcpy(buf, EXCEPTIONS[exception]);
-	end = strcpy(end, "\nError code 0x");
-	ltoa(code, end, 16);
-	panic(buf);
-}
+void idt_pic_mouse(void) {}
 
diff --git a/src/arch/amd64/panic.c b/src/arch/amd64/panic.c
index 227ecce..c034b90 100644
--- a/src/arch/amd64/panic.c
+++ b/src/arch/amd64/panic.c
@@ -6,11 +6,12 @@
 _Noreturn void _panic_impl(char *line, char *file, char *msg) {
 	cli();
 	serial_out_str("\n\n!!! PANIC !!!\n");
-	serial_out_str(msg);
-	serial_out_str("\nin file ");
+	serial_out_str("In file ");
 	serial_out_str(file);
 	serial_out_str(" at line ");
 	serial_out_str(line);
+	serial_out_str(":\n");
+	serial_out_str(msg);
 	serial_out('\n');
 	while (1) {
 		halt();