+/* traps.c
+ * Trap handling routines
+ * NetWatch system management mode administration console
+ *
+ * Copyright (c) 2008 Jacob Potter and Joshua Wise. All rights reserved.
+ * This program is free software; you can redistribute and/or modify it under
+ * the terms found in the file LICENSE in the root of this source tree.
+ *
+ */
+
#include <output.h>
#include <io.h>
#include <paging.h>
#include "traps.h"
-#define CS_SEGSEL 0x8
+#define CS_SEGSEL 0x10
+
+asm (
+ "fault_wrapper_common:\n"
+ "push %eax\n"
+ "mov %cr2, %eax\n"
+ "push %eax\n"
+ "push %esp\n"
+ "call die\n"
+);
-#define FAULT_WRAPPER(func_name) asm ( \
+#define FAULT_WRAPPER(func_name, code) asm ( \
".global " #func_name "_wrapper\n" \
#func_name "_wrapper:\n" \
- "mov %cr2, %eax\n" \
+ "mov $" #code ", %eax\n" \
+ "jmp fault_wrapper_common\n" \
+); void func_name##_wrapper(void);
+
+#define FAULT_WRAPPER1(func_name, code) asm ( \
+ ".global " #func_name "_wrapper\n" \
+ #func_name "_wrapper:\n" \
+ "mov $0, %eax\n" \
"push %eax\n" \
- "push %esp\n" \
- "call " #func_name "\n" \
+ "mov $" #code ", %eax\n" \
+ "jmp fault_wrapper_common\n" \
); void func_name##_wrapper(void);
#define WRAPPER_INSTALL(idt, idt4_value, func_name, int_number) { \
/* The 16 bits at offset 4 from the start of an interrupt gate are a
* bitfield, according to the Intel spec:
* 15 P - Segment Present - set to 1
- * 14-13 DPL - Descriptor privilege level - set to 11 for trap/int, 00 for IPI
+ * 14-13 DPL - Descriptor privilege level - set to 00, since we're always in ring 0
* 12-8 01111 for 32-bit trap gates, 01110 for 32-bit interrupt gates
* 7-0 Set to 0
- * Trap: binary 11101111 0000000, hex EF00.
- * Interrupt: binary 11101110 0000000, hex EE00.
*/
-#define TRAP 0xEF00
-#define INTERRUPT 0xEE00
+#define TRAP 0x8F00
typedef struct trap_t {
int cr2;
+ int fault_code;
int error_code;
int eip;
int cs;
int eflags;
- int esp;
- int ss;
} trap_t;
+static const char const * trapcodes[20] = {
+ "Divide by Zero",
+ "Debug Trap",
+ "NMI",
+ "Breakpoint Trap",
+ "Overflow Trap",
+ "Bound Range Fault",
+ "Invalid Opcode",
+ "Device Not Available",
+ "Double Fault",
+ "Coprocessor Overrun",
+ "Invalid TSS",
+ "Segmnet Not Present",
+ "Stack Fault",
+ "GPF",
+ "Page Fault",
+ "Reserved Trap",
+ "x87 FPE Pending",
+ "Alignment Check",
+ "Machine Check",
+ "SIMD FPE Fault"
+};
+
void die(struct trap_t * trap) {
- outputf("Error %08x %%eip %08x", trap->error_code, trap->eip);
- outputf("%%esp %08x %%eflags %08x", trap->esp, trap->eflags);
- while(1) asm("hlt");
-}
-void fault_gp(struct trap_t * trap) {
- outputf("GENERAL PROTECTION FAULT");
- die(trap);
-}
+ DBG(0x40 + trap->fault_code);
-void fault_page(struct trap_t * trap) {
- outputf("PAGE FAULT: %08x", trap->cr2);
- die(trap);
-}
-void fault_divide(struct trap_t * trap) {
- outputf("DIVISION FAULT");
- die(trap);
-}
-void double_fault(struct trap_t * trap) {
- outputf("DOUBLE FAULT");
- die(trap);
+ if (trap->fault_code < 20) {
+ outputf("---\n%s", trapcodes[trap->fault_code]);
+ } else {
+ outputf("---\nUNKNOWN FAULT");
+ }
+
+ outputf("Error %08x %%eip %08x", trap->error_code, trap->eip);
+ outputf("%%cr2 %08x %%eflags %08x", trap->cr2, trap->eflags);
+ while(1) asm("hlt");
}
-FAULT_WRAPPER(fault_gp);
-FAULT_WRAPPER(fault_page);
-FAULT_WRAPPER(fault_divide);
-FAULT_WRAPPER(double_fault);
+FAULT_WRAPPER1(fault_divide, 0);
+FAULT_WRAPPER1(fault_db, 1);
+FAULT_WRAPPER1(fault_nmi, 2);
+FAULT_WRAPPER1(fault_3, 3);
+FAULT_WRAPPER1(fault_overflow, 4);
+FAULT_WRAPPER1(fault_oob, 5);
+FAULT_WRAPPER1(fault_opcode, 6);
+FAULT_WRAPPER1(fault_enofpu, 7);
+FAULT_WRAPPER(double_fault, 8);
+FAULT_WRAPPER1(fault_fpu, 9);
+FAULT_WRAPPER(fault_invalid_tss, 10);
+FAULT_WRAPPER(fault_noseg, 11);
+FAULT_WRAPPER(fault_stack, 12);
+FAULT_WRAPPER(fault_gp, 13);
+FAULT_WRAPPER(fault_page, 14);
+FAULT_WRAPPER1(fault_fpe, 16);
+FAULT_WRAPPER(fault_ac, 17);
+FAULT_WRAPPER1(fault_machine, 18);
+FAULT_WRAPPER1(fault_other, 19);
/* pseudo_descriptor and x86_gate structs from 15-410 basis code. */
struct x86_gate {
-unsigned int filler[2]; //64 bits; or 8 bytes.
+ unsigned int filler[2]; //64 bits, or 8 bytes.
};
static struct x86_gate idt[64];
} __attribute__((packed));
void traps_install(void) {
+ DBG(0xCA);
+ int i;
struct pseudo_descriptor pdesc;
pdesc.limit = sizeof(idt) - 1;
- pdesc.linear_base = v2p(&idt);
+ pdesc.linear_base = (int)&idt; //v2p(&idt);
+
+ DBG(0xCB);
+
+ for (i = 0; i < 32; i++)
+ WRAPPER_INSTALL(idt, TRAP, fault_other, i);
WRAPPER_INSTALL(idt, TRAP, fault_divide, T_DIVIDE_ERROR);
+ WRAPPER_INSTALL(idt, TRAP, fault_db, T_DEBUG);
+ WRAPPER_INSTALL(idt, TRAP, fault_nmi, T_NMI);
+ WRAPPER_INSTALL(idt, TRAP, fault_3, T_INT3);
+ WRAPPER_INSTALL(idt, TRAP, fault_overflow, T_OVERFLOW);
+ WRAPPER_INSTALL(idt, TRAP, fault_oob, T_OUT_OF_BOUNDS);
+ WRAPPER_INSTALL(idt, TRAP, fault_opcode, T_INVALID_OPCODE);
+ WRAPPER_INSTALL(idt, TRAP, fault_enofpu, T_NO_FPU);
+ WRAPPER_INSTALL(idt, TRAP, double_fault, T_DOUBLE_FAULT);
+ WRAPPER_INSTALL(idt, TRAP, fault_fpu, T_FPU_FAULT);
+ WRAPPER_INSTALL(idt, TRAP, fault_invalid_tss, T_INVALID_TSS);
+ WRAPPER_INSTALL(idt, TRAP, fault_noseg, T_SEGMENT_NOT_PRESENT);
+ WRAPPER_INSTALL(idt, TRAP, fault_stack, T_STACK_FAULT);
WRAPPER_INSTALL(idt, TRAP, fault_gp, T_GENERAL_PROTECTION);
WRAPPER_INSTALL(idt, TRAP, fault_page, T_PAGE_FAULT);
- WRAPPER_INSTALL(idt, TRAP, double_fault, T_DOUBLE_FAULT);
+ WRAPPER_INSTALL(idt, TRAP, fault_fpe, T_FLOATING_POINT_ERROR);
+ WRAPPER_INSTALL(idt, TRAP, fault_ac, T_ALIGNMENT_CHECK);
+ WRAPPER_INSTALL(idt, TRAP, fault_machine, T_MACHINE_CHECK);
- outb(0x80, 0xCC);
+ DBG(0xCC);
asm volatile("lidt %0" : : "m" (pdesc.limit));
- outb(0x80, 0xCD);
+ DBG(0xCE);
}
git.joshuawise.com / netwatch.git / blobdiff