135 lines
		
	
	
		
			3.9 KiB
		
	
	
	
		
			C
		
	
	
		
			Executable File
		
	
	
	
	
			
		
		
	
	
			135 lines
		
	
	
		
			3.9 KiB
		
	
	
	
		
			C
		
	
	
		
			Executable File
		
	
	
	
	
| /* This file contains a simple exception handler.  Exceptions in user
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|  * processes are converted to signals. Exceptions in a kernel task cause
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|  * a panic.
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|  */
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| 
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| #include "../../kernel.h"
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| #include "proto.h"
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| #include <signal.h>
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| #include "../../proc.h"
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| 
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| /*===========================================================================*
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|  *				exception				     *
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|  *===========================================================================*/
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| PUBLIC void exception(vec_nr, trap_errno, old_eip, old_cs, old_eflags)
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| unsigned vec_nr;
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| u32_t trap_errno;
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| u32_t old_eip;
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| U16_t old_cs;
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| u32_t old_eflags;
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| {
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| /* An exception or unexpected interrupt has occurred. */
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| 
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|   struct ex_s {
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| 	char *msg;
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| 	int signum;
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| 	int minprocessor;
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|   };
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|   static struct ex_s ex_data[] = {
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| 	{ "Divide error", SIGFPE, 86 },
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| 	{ "Debug exception", SIGTRAP, 86 },
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| 	{ "Nonmaskable interrupt", SIGBUS, 86 },
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| 	{ "Breakpoint", SIGEMT, 86 },
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| 	{ "Overflow", SIGFPE, 86 },
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| 	{ "Bounds check", SIGFPE, 186 },
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| 	{ "Invalid opcode", SIGILL, 186 },
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| 	{ "Coprocessor not available", SIGFPE, 186 },
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| 	{ "Double fault", SIGBUS, 286 },
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| 	{ "Copressor segment overrun", SIGSEGV, 286 },
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| 	{ "Invalid TSS", SIGSEGV, 286 },
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| 	{ "Segment not present", SIGSEGV, 286 },
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| 	{ "Stack exception", SIGSEGV, 286 },	/* STACK_FAULT already used */
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| 	{ "General protection", SIGSEGV, 286 },
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| 	{ "Page fault", SIGSEGV, 386 },		/* not close */
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| 	{ NIL_PTR, SIGILL, 0 },			/* probably software trap */
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| 	{ "Coprocessor error", SIGFPE, 386 },
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|   };
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|   register struct ex_s *ep;
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|   struct proc *saved_proc;
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| 
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|   /* Save proc_ptr, because it may be changed by debug statements. */
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|   saved_proc = proc_ptr;	
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| 
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|   ep = &ex_data[vec_nr];
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| 
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|   if (vec_nr == 2) {		/* spurious NMI on some machines */
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| 	kprintf("got spurious NMI\n");
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| 	return;
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|   }
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| 
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|   /* If an exception occurs while running a process, the k_reenter variable 
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|    * will be zero. Exceptions in interrupt handlers or system traps will make 
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|    * k_reenter larger than zero.
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|    */
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|   if (k_reenter == 0 && ! iskernelp(saved_proc)) {
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| #if 0
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| 	{
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| 		kprintf(
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| "exception for process %d, endpoint %d ('%s'), pc = 0x%x:0x%x, sp = 0x%x:0x%x\n",
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| 			proc_nr(saved_proc), saved_proc->p_endpoint,
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| 			saved_proc->p_name,
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| 			saved_proc->p_reg.cs, saved_proc->p_reg.pc,
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| 			saved_proc->p_reg.ss, saved_proc->p_reg.sp);
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|   		kprintf(
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|   "vec_nr= %d, trap_errno= 0x%lx, eip= 0x%lx, cs= 0x%x, eflags= 0x%lx\n",
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| 			vec_nr, (unsigned long)trap_errno,
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| 			(unsigned long)old_eip, old_cs,
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| 			(unsigned long)old_eflags);
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| #if DEBUG_STACKTRACE
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| 		stacktrace(saved_proc);
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| #endif
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| 	}
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| #endif
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| 
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| 	cause_sig(proc_nr(saved_proc), ep->signum);
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| 	return;
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|   }
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| 
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|   /* Exception in system code. This is not supposed to happen. */
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|   if (ep->msg == NIL_PTR || machine.processor < ep->minprocessor)
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| 	kprintf("\nIntel-reserved exception %d\n", vec_nr);
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|   else
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| 	kprintf("\n%s\n", ep->msg);
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|   kprintf("k_reenter = %d ", k_reenter);
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|   kprintf("process %d (%s), ", proc_nr(saved_proc), saved_proc->p_name);
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|   kprintf("pc = %u:0x%x", (unsigned) saved_proc->p_reg.cs,
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|   (unsigned) saved_proc->p_reg.pc);
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|   kprintf(
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|   "vec_nr= %d, trap_errno= 0x%lx, eip= 0x%lx, cs= 0x%x, eflags= 0x%lx\n",
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| 	vec_nr, (unsigned long)trap_errno,
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| 	(unsigned long)old_eip, old_cs, (unsigned long)old_eflags);
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| 
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|   panic("exception in a kernel task", NO_NUM);
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| }
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| 
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| #if DEBUG_STACKTRACE
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| /*===========================================================================*
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|  *				stacktrace				     *
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|  *===========================================================================*/
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| PUBLIC void stacktrace(struct proc *proc)
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| {
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| 	reg_t bp, v_bp, v_pc, v_hbp;
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| 
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| 	v_bp = proc->p_reg.fp;
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| 
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| 	kprintf("stacktrace: ");
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| 	while(v_bp) {
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| 		phys_bytes p;
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| 		if(!(p = umap_local(proc, D, v_bp, sizeof(v_bp)))) {
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| 			kprintf("(bad bp %lx)", v_bp);
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| 			break;
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| 		}
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| 		phys_copy(p+sizeof(v_pc), vir2phys(&v_pc), sizeof(v_pc));
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| 		phys_copy(p, vir2phys(&v_hbp), sizeof(v_hbp));
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| 		kprintf("0x%lx ", (unsigned long) v_pc);
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| 		if(v_hbp != 0 && v_hbp <= v_bp) {
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| 			kprintf("(bad hbp %lx)", v_hbp);
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| 			break;
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| 		}
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| 		v_bp = v_hbp;
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| 	}
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| 	kprintf("\n");
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| }
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| #endif
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| 
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