diff --git a/sys/amd64/amd64/db_trace.c b/sys/amd64/amd64/db_trace.c
index 9e300cf2ec7d..5e475a4a1c55 100644
--- a/sys/amd64/amd64/db_trace.c
+++ b/sys/amd64/amd64/db_trace.c
@@ -23,7 +23,7 @@
  * any improvements or extensions that they make and grant Carnegie the
  * rights to redistribute these changes.
  *
- *	$Id: db_trace.c,v 1.2 1993/10/16 14:14:56 rgrimes Exp $
+ *	$Id: db_trace.c,v 1.3 1993/12/19 00:50:01 wollman Exp $
  */
 
 #include "param.h"
@@ -73,8 +73,10 @@ struct i386_frame {
 
 #define	TRAP		1
 #define	INTERRUPT	2
+#define	SYSCALL		3
 
 db_addr_t	db_trap_symbol_value = 0;
+db_addr_t	db_syscall_symbol_value = 0;
 db_addr_t	db_kdintr_symbol_value = 0;
 boolean_t	db_trace_symbols_found = FALSE;
 
@@ -86,6 +88,8 @@ db_find_trace_symbols()
 	    db_trap_symbol_value = (db_addr_t) value;
 	if (db_value_of_name("_kdintr", &value))
 	    db_kdintr_symbol_value = (db_addr_t) value;
+	if (db_value_of_name("_syscall", &value))
+	    db_syscall_symbol_value = (db_addr_t) value;
 	db_trace_symbols_found = TRUE;
 }
 
@@ -135,26 +139,43 @@ db_nextframe(fp, ip, argp, is_trap)
 {
 	struct i386_saved_state *saved_regs;
 
-	if (is_trap == 0) {
+	switch (is_trap) {
+	case 0:
 	    *ip = (db_addr_t)
 			db_get_value((int) &(*fp)->f_retaddr, 4, FALSE);
 	    *fp = (struct i386_frame *)
 			db_get_value((int) &(*fp)->f_frame, 4, FALSE);
-	} else {
+	    break;
+	case TRAP:
+	default:
 	    /*
 	     * We know that trap() has 1 argument and we know that
 	     * it is an (int *).
 	     */
+#if 0
 	    saved_regs = (struct i386_saved_state *)
 			db_get_value((int)argp, 4, FALSE);
+#endif
+	    saved_regs = (struct i386_saved_state *)argp;
 	    db_printf("--- trap (number %d) ---\n",
 		      saved_regs->tf_trapno & 0xffff);
 	    db_printsym(saved_regs->tf_eip, DB_STGY_XTRN);
 	    db_printf(":\n");
 	    *fp = (struct i386_frame *)saved_regs->tf_ebp;
 	    *ip = (db_addr_t)saved_regs->tf_eip;
-	}
+	    break;
 
+	case SYSCALL: {
+	    struct trapframe	*saved_regs = (struct trapframe *)argp;
+
+	    db_printf("--- syscall (number %d) ---\n", saved_regs->tf_eax);
+	    db_printsym(saved_regs->tf_eip, DB_STGY_XTRN);
+	    db_printf(":\n");
+	    *fp = (struct i386_frame *)saved_regs->tf_ebp;
+	    *ip = (db_addr_t)saved_regs->tf_eip;
+	    }
+	    break;
+	}
 }
 
 void
@@ -171,8 +192,10 @@ db_stack_trace_cmd(addr, have_addr, count, modif)
 	boolean_t	kernel_only = TRUE;
 	boolean_t	trace_thread = FALSE;
 
+#if 0
 	if (!db_trace_symbols_found)
 	    db_find_trace_symbols();
+#endif
 
 	{
 	    register char *cp = modif;
@@ -203,38 +226,84 @@ db_stack_trace_cmd(addr, have_addr, count, modif)
 
 	lastframe = 0;
 	while (count-- && frame != 0) {
-	    register int narg;
+	    int		narg;
 	    char *	name;
 	    db_expr_t	offset;
+	    db_sym_t	sym;
+#define MAXNARG	16
+	    char	*argnames[MAXNARG], **argnp = NULL;
 
-	    if (INKERNEL((int)frame) && callpc == db_trap_symbol_value) {
+	    sym = db_search_symbol(callpc, DB_STGY_ANY, &offset);
+	    db_symbol_values(sym, &name, NULL);
+
+	    if (lastframe == 0 && sym == NULL) {
+		/* Symbol not found, peek at code */
+		int	instr = db_get_value(callpc, 4, FALSE);
+
+		offset = 1;
+		if ((instr & 0x00ffffff) == 0x00e58955 ||
+				/* enter: pushl %ebp, movl %esp, %ebp */
+			(instr & 0x0000ffff) == 0x0000e589
+				/* enter+1: movl %esp, %ebp */	) {
+			offset = 0;
+		}
+	    }
+#define STRCMP(s1,s2) ((s1) && (s2) && strcmp((s1), (s2)) == 0)
+	    if (INKERNEL((int)frame) && STRCMP(name, "_trap")) {
 		narg = 1;
 		is_trap = TRAP;
 	    }
 	    else
-	    if (INKERNEL((int)frame) && callpc == db_kdintr_symbol_value) {
+	    if (INKERNEL((int)frame) && STRCMP(name, "_kdintr")) {
 		is_trap = INTERRUPT;
 		narg = 0;
 	    }
+	    else
+	    if (INKERNEL((int)frame) && STRCMP(name, "_syscall")) {
+		is_trap = SYSCALL;
+		narg = 0;
+	    }
+#undef STRCMP
 	    else {
 		is_trap = 0;
-		narg = db_numargs(frame);
+		narg = MAXNARG;
+		if (db_sym_numargs(sym, &narg, argnames)) {
+			argnp = argnames;
+		} else {
+			narg = db_numargs(frame);
+		}
 	    }
 
-	    db_find_sym_and_offset(callpc, &name, &offset);
 	    db_printf("%s(", name);
 
-	    argp = &frame->f_arg0;
+	    if (lastframe == 0 && offset == 0 && !have_addr) {
+		/*
+		 * We have a breakpoint before the frame is set up
+		 * Use %esp instead
+		 */
+		argp = &((struct i386_frame *)(ddb_regs.tf_esp-4))->f_arg0;
+	    } else
+		argp = &frame->f_arg0;
+
 	    while (narg) {
+		if (argnp)
+			db_printf("%s=", *argnp++);
 		db_printf("%x", db_get_value((int)argp, 4, FALSE));
 		argp++;
 		if (--narg != 0)
 		    db_printf(",");
 	    }
 	    db_printf(") at ");
-	    db_printsym(callpc, DB_STGY_XTRN);
+	    db_printsym(callpc, DB_STGY_PROC);
 	    db_printf("\n");
 
+	    if (lastframe == 0 && offset == 0 && !have_addr) {
+		/* Frame really belongs to next callpc */
+		lastframe = (struct i386_frame *)(ddb_regs.tf_esp-4);
+		callpc = (db_addr_t)db_get_value((int)&lastframe->f_retaddr, 4, FALSE);
+		continue;
+	    }
+
 	    lastframe = frame;
 	    db_nextframe(&frame, &callpc, &frame->f_arg0, is_trap);
 
@@ -257,7 +326,7 @@ db_stack_trace_cmd(addr, have_addr, count, modif)
 	    else {
 		/* in user */
 		if (frame <= lastframe) {
-		    db_printf("Bad frame pointer: 0x%x\n", frame);
+		    db_printf("Bad user frame pointer: 0x%x\n", frame);
 		    break;
 		}
 	    }
diff --git a/sys/amd64/amd64/exception.S b/sys/amd64/amd64/exception.S
index d6de8748a5cb..93aed946f655 100644
--- a/sys/amd64/amd64/exception.S
+++ b/sys/amd64/amd64/exception.S
@@ -30,7 +30,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- *	$Id$
+ *	$Id: exception.s,v 1.1 1993/11/13 02:24:57 davidg Exp $
  */
 
 #include "npx.h"				/* NNPX */
@@ -181,7 +181,7 @@ calltrap:
 	 * Return through doreti to handle ASTs.  Have to change trap frame
 	 * to interrupt frame.
 	 */
-	movl	$T_ASTFLT,4+4+32(%esp)		/* new trap type (err code not used) */
+	movl	$T_ASTFLT,TF_TRAPNO(%esp)	/* new trap type (err code not used) */
 	pushl	_cpl
 	pushl	$0				/* dummy unit */
 	jmp	doreti
@@ -195,8 +195,8 @@ calltrap:
 bpttraps:
 	pushal
 	nop
-	pushl	%es
 	pushl	%ds
+	pushl	%es
 	movl	$KDSEL,%eax
 	movl	%ax,%ds
 	movl	%ax,%es
@@ -211,38 +211,24 @@ bpttraps:
  */
 	SUPERALIGN_TEXT
 IDTVEC(syscall)
-	pushfl	/* only for stupid carry bit and more stupid wait3 cc kludge */
-		/* XXX - also for direction flag (bzero, etc. clear it) */
-	pushal	/* only need eax,ecx,edx - trap resaves others */
+	pushfl					/* Room for tf_err */
+	pushfl					/* Room for tf_trapno */
+	pushal
 	nop
+	pushl	%ds
+	pushl	%es
 	movl	$KDSEL,%eax			/* switch to kernel segments */
 	movl	%ax,%ds
 	movl	%ax,%es
+	movl	TF_ERR(%esp),%eax		/* copy eflags from tf_err to fs_eflags */
+	movl	%eax,TF_EFLAGS(%esp)
+	movl	$0,TF_ERR(%esp)			/* zero tf_err */
 	incl	_cnt+V_SYSCALL
 	call	_syscall
 	/*
-	 * Return through doreti to handle ASTs.  Have to change syscall frame
-	 * to interrupt frame.
-	 *
-	 * XXX - we should have set up the frame earlier to avoid the
-	 * following popal/pushal (not much can be done to avoid shuffling
-	 * the flags).  Consistent frames would simplify things all over.
+	 * Return through doreti to handle ASTs.
 	 */
-	movl	32+0(%esp),%eax			/* old flags, shuffle to above cs:eip */
-	movl	32+4(%esp),%ebx			/* `int' frame should have been ef, eip, cs */
-	movl	32+8(%esp),%ecx
-	movl	%ebx,32+0(%esp)
-	movl	%ecx,32+4(%esp)
-	movl	%eax,32+8(%esp)
-	popal
-	nop
-	pushl	$0				/* dummy error code */
-	pushl	$T_ASTFLT
-	pushal
-	nop
-	movl	__udatasel,%eax			/* switch back to user segments */
-	pushl	%eax				/* XXX - better to preserve originals? */
-	pushl	%eax
+	movl	$T_ASTFLT,TF_TRAPNO(%esp)	/* new trap type (err code not used) */
 	pushl	_cpl
 	pushl	$0
 	jmp	doreti
diff --git a/sys/amd64/amd64/exception.s b/sys/amd64/amd64/exception.s
index d6de8748a5cb..93aed946f655 100644
--- a/sys/amd64/amd64/exception.s
+++ b/sys/amd64/amd64/exception.s
@@ -30,7 +30,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- *	$Id$
+ *	$Id: exception.s,v 1.1 1993/11/13 02:24:57 davidg Exp $
  */
 
 #include "npx.h"				/* NNPX */
@@ -181,7 +181,7 @@ calltrap:
 	 * Return through doreti to handle ASTs.  Have to change trap frame
 	 * to interrupt frame.
 	 */
-	movl	$T_ASTFLT,4+4+32(%esp)		/* new trap type (err code not used) */
+	movl	$T_ASTFLT,TF_TRAPNO(%esp)	/* new trap type (err code not used) */
 	pushl	_cpl
 	pushl	$0				/* dummy unit */
 	jmp	doreti
@@ -195,8 +195,8 @@ calltrap:
 bpttraps:
 	pushal
 	nop
-	pushl	%es
 	pushl	%ds
+	pushl	%es
 	movl	$KDSEL,%eax
 	movl	%ax,%ds
 	movl	%ax,%es
@@ -211,38 +211,24 @@ bpttraps:
  */
 	SUPERALIGN_TEXT
 IDTVEC(syscall)
-	pushfl	/* only for stupid carry bit and more stupid wait3 cc kludge */
-		/* XXX - also for direction flag (bzero, etc. clear it) */
-	pushal	/* only need eax,ecx,edx - trap resaves others */
+	pushfl					/* Room for tf_err */
+	pushfl					/* Room for tf_trapno */
+	pushal
 	nop
+	pushl	%ds
+	pushl	%es
 	movl	$KDSEL,%eax			/* switch to kernel segments */
 	movl	%ax,%ds
 	movl	%ax,%es
+	movl	TF_ERR(%esp),%eax		/* copy eflags from tf_err to fs_eflags */
+	movl	%eax,TF_EFLAGS(%esp)
+	movl	$0,TF_ERR(%esp)			/* zero tf_err */
 	incl	_cnt+V_SYSCALL
 	call	_syscall
 	/*
-	 * Return through doreti to handle ASTs.  Have to change syscall frame
-	 * to interrupt frame.
-	 *
-	 * XXX - we should have set up the frame earlier to avoid the
-	 * following popal/pushal (not much can be done to avoid shuffling
-	 * the flags).  Consistent frames would simplify things all over.
+	 * Return through doreti to handle ASTs.
 	 */
-	movl	32+0(%esp),%eax			/* old flags, shuffle to above cs:eip */
-	movl	32+4(%esp),%ebx			/* `int' frame should have been ef, eip, cs */
-	movl	32+8(%esp),%ecx
-	movl	%ebx,32+0(%esp)
-	movl	%ecx,32+4(%esp)
-	movl	%eax,32+8(%esp)
-	popal
-	nop
-	pushl	$0				/* dummy error code */
-	pushl	$T_ASTFLT
-	pushal
-	nop
-	movl	__udatasel,%eax			/* switch back to user segments */
-	pushl	%eax				/* XXX - better to preserve originals? */
-	pushl	%eax
+	movl	$T_ASTFLT,TF_TRAPNO(%esp)	/* new trap type (err code not used) */
 	pushl	_cpl
 	pushl	$0
 	jmp	doreti
diff --git a/sys/amd64/amd64/fpu.c b/sys/amd64/amd64/fpu.c
index 0e90bff2433f..796dfbbae406 100644
--- a/sys/amd64/amd64/fpu.c
+++ b/sys/amd64/amd64/fpu.c
@@ -32,7 +32,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)npx.c	7.2 (Berkeley) 5/12/91
- *	$Id: npx.c,v 1.4 1993/11/03 00:29:19 paul Exp $
+ *	$Id: npx.c,v 1.5 1993/11/03 23:32:35 paul Exp $
  */
 
 #include "npx.h"
@@ -439,7 +439,6 @@ npxintr(frame)
 		 * just before it is used).
 		 */
 		curproc->p_regs = (int *)&frame.if_es;
-		curpcb->pcb_flags |= FM_TRAP;	/* used by sendsig */
 #ifdef notyet
 		/*
 		 * Encode the appropriate code for detailed information on
@@ -450,7 +449,6 @@ npxintr(frame)
 		code = 0;	/* XXX */
 #endif
 		trapsignal(curproc, SIGFPE, code);
-		curpcb->pcb_flags &= ~FM_TRAP;
 	} else {
 		/*
 		 * Nested interrupt.  These losers occur when:
diff --git a/sys/amd64/amd64/machdep.c b/sys/amd64/amd64/machdep.c
index 417147462779..f47d9e62ed47 100644
--- a/sys/amd64/amd64/machdep.c
+++ b/sys/amd64/amd64/machdep.c
@@ -35,7 +35,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)machdep.c	7.4 (Berkeley) 6/3/91
- *	$Id: machdep.c,v 1.22 1993/12/19 00:50:03 wollman Exp $
+ *	$Id: machdep.c,v 1.23 1993/12/22 13:12:04 davidg Exp $
  */
 
 #include "npx.h"
@@ -418,7 +418,6 @@ sendsig(catcher, sig, mask, code)
 
 	regs = p->p_regs;
         oonstack = ps->ps_onstack;
-	frmtrap = curpcb->pcb_flags & FM_TRAP;
 	/*
 	 * Allocate and validate space for the signal handler
 	 * context. Note that if the stack is in P0 space, the
@@ -431,12 +430,8 @@ sendsig(catcher, sig, mask, code)
 				- sizeof(struct sigframe));
                 ps->ps_onstack = 1;
 	} else {
-		if (frmtrap)
-			fp = (struct sigframe *)(regs[tESP]
-				- sizeof(struct sigframe));
-		else
-			fp = (struct sigframe *)(regs[sESP]
-				- sizeof(struct sigframe));
+		fp = (struct sigframe *)(regs[tESP]
+			- sizeof(struct sigframe));
 	}
 
 	if (useracc((caddr_t)fp, sizeof (struct sigframe), B_WRITE) == 0) {
@@ -463,35 +458,21 @@ sendsig(catcher, sig, mask, code)
 	fp->sf_handler = catcher;
 
 	/* save scratch registers */
-	if(frmtrap) {
-		fp->sf_eax = regs[tEAX];
-		fp->sf_edx = regs[tEDX];
-		fp->sf_ecx = regs[tECX];
-	} else {
-		fp->sf_eax = regs[sEAX];
-		fp->sf_edx = regs[sEDX];
-		fp->sf_ecx = regs[sECX];
-	}
+	fp->sf_eax = regs[tEAX];
+	fp->sf_edx = regs[tEDX];
+	fp->sf_ecx = regs[tECX];
+
 	/*
 	 * Build the signal context to be used by sigreturn.
 	 */
 	fp->sf_sc.sc_onstack = oonstack;
 	fp->sf_sc.sc_mask = mask;
-	if(frmtrap) {
-		fp->sf_sc.sc_sp = regs[tESP];
-		fp->sf_sc.sc_fp = regs[tEBP];
-		fp->sf_sc.sc_pc = regs[tEIP];
-		fp->sf_sc.sc_ps = regs[tEFLAGS];
-		regs[tESP] = (int)fp;
-		regs[tEIP] = (int)((struct pcb *)kstack)->pcb_sigc;
-	} else {
-		fp->sf_sc.sc_sp = regs[sESP];
-		fp->sf_sc.sc_fp = regs[sEBP];
-		fp->sf_sc.sc_pc = regs[sEIP];
-		fp->sf_sc.sc_ps = regs[sEFLAGS];
-		regs[sESP] = (int)fp;
-		regs[sEIP] = (int)((struct pcb *)kstack)->pcb_sigc;
-	}
+	fp->sf_sc.sc_sp = regs[tESP];
+	fp->sf_sc.sc_fp = regs[tEBP];
+	fp->sf_sc.sc_pc = regs[tEIP];
+	fp->sf_sc.sc_ps = regs[tEFLAGS];
+	regs[tESP] = (int)fp;
+	regs[tEIP] = (int)((struct pcb *)kstack)->pcb_sigc;
 }
 
 /*
@@ -519,7 +500,7 @@ sigreturn(p, uap, retval)
 	register int *regs = p->p_regs;
 
 	/*
-	 * (XXX old comment) regs[sESP] points to the return address.
+	 * (XXX old comment) regs[tESP] points to the return address.
 	 * The user scp pointer is above that.
 	 * The return address is faked in the signal trampoline code
 	 * for consistency.
@@ -532,9 +513,9 @@ sigreturn(p, uap, retval)
 		return(EINVAL);
 
 	/* restore scratch registers */
-	regs[sEAX] = fp->sf_eax ;
-	regs[sEDX] = fp->sf_edx ;
-	regs[sECX] = fp->sf_ecx ;
+	regs[tEAX] = fp->sf_eax ;
+	regs[tEDX] = fp->sf_edx ;
+	regs[tECX] = fp->sf_ecx ;
 
 	if (useracc((caddr_t)scp, sizeof (*scp), 0) == 0)
 		return(EINVAL);
@@ -546,10 +527,10 @@ sigreturn(p, uap, retval)
         p->p_sigacts->ps_onstack = scp->sc_onstack & 01;
 	p->p_sigmask = scp->sc_mask &~
 	    (sigmask(SIGKILL)|sigmask(SIGCONT)|sigmask(SIGSTOP));
-	regs[sEBP] = scp->sc_fp;
-	regs[sESP] = scp->sc_sp;
-	regs[sEIP] = scp->sc_pc;
-	regs[sEFLAGS] = scp->sc_ps;
+	regs[tEBP] = scp->sc_fp;
+	regs[tESP] = scp->sc_sp;
+	regs[tEIP] = scp->sc_pc;
+	regs[tEFLAGS] = scp->sc_ps;
 	return(EJUSTRETURN);
 }
 
@@ -762,13 +743,18 @@ initcpu()
  * Clear registers on exec
  */
 void
-setregs(p, entry)
+setregs(p, entry, stack)
 	struct proc *p;
 	u_long entry;
+	u_long stack;
 {
-
-	p->p_regs[sEBP] = 0;	/* bottom of the fp chain */
-	p->p_regs[sEIP] = entry;
+	p->p_regs[tEBP] = 0;	/* bottom of the fp chain */
+	p->p_regs[tEIP] = entry;
+	p->p_regs[tESP] = stack;
+	p->p_regs[tSS] = _udatasel;
+	p->p_regs[tDS] = _udatasel;
+	p->p_regs[tES] = _udatasel;
+	p->p_regs[tCS] = _ucodesel;
 
 	p->p_addr->u_pcb.pcb_flags = 0;	/* no fp at all */
 	load_cr0(rcr0() | CR0_TS);	/* start emulating */
@@ -1153,7 +1139,7 @@ init386(first)
 	x = (int) &IDTVEC(syscall);
 	gdp->gd_looffset = x++;
 	gdp->gd_selector = GSEL(GCODE_SEL,SEL_KPL);
-	gdp->gd_stkcpy = 0;
+	gdp->gd_stkcpy = 1;	/* Leaves room for eflags like a trap */
 	gdp->gd_type = SDT_SYS386CGT;
 	gdp->gd_dpl = SEL_UPL;
 	gdp->gd_p = 1;
@@ -1268,35 +1254,24 @@ _remque(element)
 
 int
 ptrace_set_pc (struct proc *p, unsigned int addr) {
-	struct pcb *pcb;
 	void *regs = (char*)p->p_addr +
 		((char*) p->p_regs - (char*) kstack);
 
-	pcb = &p->p_addr->u_pcb;
-	if (pcb->pcb_flags & FM_TRAP)
-		((struct trapframe *)regs)->tf_eip = addr;
-	else
-		((struct syscframe *)regs)->sf_eip = addr;
+	((struct trapframe *)regs)->tf_eip = addr;
 	return 0;
 }
 
 int
 ptrace_single_step (struct proc *p) {
-	struct pcb *pcb;
 	void *regs = (char*)p->p_addr +
 		((char*) p->p_regs - (char*) kstack);
 
-	pcb = &p->p_addr->u_pcb;
-	if (pcb->pcb_flags & FM_TRAP)
-		((struct trapframe *)regs)->tf_eflags |= PSL_T;
-	else
-		((struct syscframe *)regs)->sf_eflags |= PSL_T;
+	((struct trapframe *)regs)->tf_eflags |= PSL_T;
 	return 0;
 }
 
 /*
- * Copy the registers to user-space.  This is tedious because
- * we essentially duplicate code for trapframe and syscframe. *sigh*
+ * Copy the registers to user-space.
  */
 
 int
@@ -1325,50 +1300,24 @@ int
 fill_regs(struct proc *p, struct regs *regs) {
 	int error;
 	struct trapframe *tp;
-	struct syscframe *sp;
-	struct pcb *pcb;
 	void *ptr = (char*)p->p_addr +
 		((char*) p->p_regs - (char*) kstack);
 
-	pcb = &p->p_addr->u_pcb;
-	if (pcb->pcb_flags & FM_TRAP) {
-		tp = ptr;
-		regs->r_es = tp->tf_es;
-		regs->r_ds = tp->tf_ds;
-		regs->r_edi = tp->tf_edi;
-		regs->r_esi = tp->tf_esi;
-		regs->r_ebp = tp->tf_ebp;
-		regs->r_ebx = tp->tf_ebx;
-		regs->r_edx = tp->tf_edx;
-		regs->r_ecx = tp->tf_ecx;
-		regs->r_eax = tp->tf_eax;
-		regs->r_eip = tp->tf_eip;
-		regs->r_cs = tp->tf_cs;
-		regs->r_eflags = tp->tf_eflags;
-		regs->r_esp = tp->tf_esp;
-		regs->r_ss = tp->tf_ss;
-	} else {
-		sp = ptr;
-		/*
-		 * No sf_es or sf_ds... dunno why.
-		 */
-		/*
-		 * regs.r_es = sp->sf_es;
-		 * regs.r_ds = sp->sf_ds;
-		 */
-		regs->r_edi = sp->sf_edi;
-		regs->r_esi = sp->sf_esi;
-		regs->r_ebp = sp->sf_ebp;
-		regs->r_ebx = sp->sf_ebx;
-		regs->r_edx = sp->sf_edx;
-		regs->r_ecx = sp->sf_ecx;
-		regs->r_eax = sp->sf_eax;
-		regs->r_eip = sp->sf_eip;
-		regs->r_cs = sp->sf_cs;
-		regs->r_eflags = sp->sf_eflags;
-		regs->r_esp = sp->sf_esp;
-		regs->r_ss = sp->sf_ss;
-	}
+	tp = ptr;
+	regs->r_es = tp->tf_es;
+	regs->r_ds = tp->tf_ds;
+	regs->r_edi = tp->tf_edi;
+	regs->r_esi = tp->tf_esi;
+	regs->r_ebp = tp->tf_ebp;
+	regs->r_ebx = tp->tf_ebx;
+	regs->r_edx = tp->tf_edx;
+	regs->r_ecx = tp->tf_ecx;
+	regs->r_eax = tp->tf_eax;
+	regs->r_eip = tp->tf_eip;
+	regs->r_cs = tp->tf_cs;
+	regs->r_eflags = tp->tf_eflags;
+	regs->r_esp = tp->tf_esp;
+	regs->r_ss = tp->tf_ss;
 	return 0;
 }
 
@@ -1376,122 +1325,27 @@ int
 set_regs (struct proc *p, struct regs *regs) {
 	int error;
 	struct trapframe *tp;
-	struct syscframe *sp;
-	struct pcb *pcb;
 	void *ptr = (char*)p->p_addr +
 		((char*) p->p_regs - (char*) kstack);
 
-	pcb = &p->p_addr->u_pcb;
-	if (pcb->pcb_flags & FM_TRAP) {
-		tp = ptr;
-		tp->tf_es = regs->r_es;
-		tp->tf_ds = regs->r_ds;
-		tp->tf_edi = regs->r_edi;
-		tp->tf_esi = regs->r_esi;
-		tp->tf_ebp = regs->r_ebp;
-		tp->tf_ebx = regs->r_ebx;
-		tp->tf_edx = regs->r_edx;
-		tp->tf_ecx = regs->r_ecx;
-		tp->tf_eax = regs->r_eax;
-		tp->tf_eip = regs->r_eip;
-		tp->tf_cs = regs->r_cs;
-		tp->tf_eflags = regs->r_eflags;
-		tp->tf_esp = regs->r_esp;
-		tp->tf_ss = regs->r_ss;
-	} else {
-		sp = ptr;
-		/*
-		 * No sf_es or sf_ds members, dunno why...
-		 */
-		/*
-		 * sp->sf_es = regs.r_es;
-		 * sp->sf_ds = regs.r_ds;
-		 */
-		sp->sf_edi = regs->r_edi;
-		sp->sf_esi = regs->r_esi;
-		sp->sf_ebp = regs->r_ebp;
-		sp->sf_ebx = regs->r_ebx;
-		sp->sf_edx = regs->r_edx;
-		sp->sf_ecx = regs->r_ecx;
-		sp->sf_eax = regs->r_eax;
-		sp->sf_eip = regs->r_eip;
-		sp->sf_cs = regs->r_cs;
-		sp->sf_eflags = regs->r_eflags;
-		sp->sf_esp = regs->r_esp;
-		sp->sf_ss = regs->r_ss;
-	}
+	tp = ptr;
+	tp->tf_es = regs->r_es;
+	tp->tf_ds = regs->r_ds;
+	tp->tf_edi = regs->r_edi;
+	tp->tf_esi = regs->r_esi;
+	tp->tf_ebp = regs->r_ebp;
+	tp->tf_ebx = regs->r_ebx;
+	tp->tf_edx = regs->r_edx;
+	tp->tf_ecx = regs->r_ecx;
+	tp->tf_eax = regs->r_eax;
+	tp->tf_eip = regs->r_eip;
+	tp->tf_cs = regs->r_cs;
+	tp->tf_eflags = regs->r_eflags;
+	tp->tf_esp = regs->r_esp;
+	tp->tf_ss = regs->r_ss;
 	return 0;
 }
 
-#ifdef SLOW_OLD_COPYSTRS
-vmunaccess() {}
-
-#if 0		/* assembler versions now in locore.s */
-/*
- * Below written in C to allow access to debugging code
- */
-copyinstr(fromaddr, toaddr, maxlength, lencopied) u_int *lencopied, maxlength;
-	void *toaddr, *fromaddr; {
-	int c,tally;
-
-	tally = 0;
-	while (maxlength--) {
-		c = fubyte(fromaddr++);
-		if (c == -1) {
-			if(lencopied) *lencopied = tally;
-			return(EFAULT);
-		}
-		tally++;
-		*(char *)toaddr++ = (char) c;
-		if (c == 0){
-			if(lencopied) *lencopied = (u_int)tally;
-			return(0);
-		}
-	}
-	if(lencopied) *lencopied = (u_int)tally;
-	return(ENAMETOOLONG);
-}
-
-copyoutstr(fromaddr, toaddr, maxlength, lencopied) u_int *lencopied, maxlength;
-	void *fromaddr, *toaddr; {
-	int c;
-	int tally;
-
-	tally = 0;
-	while (maxlength--) {
-		c = subyte(toaddr++, *(char *)fromaddr);
-		if (c == -1) return(EFAULT);
-		tally++;
-		if (*(char *)fromaddr++ == 0){
-			if(lencopied) *lencopied = tally;
-			return(0);
-		}
-	}
-	if(lencopied) *lencopied = tally;
-	return(ENAMETOOLONG);
-}
-
-#endif /* SLOW_OLD_COPYSTRS */
-
-copystr(fromaddr, toaddr, maxlength, lencopied) u_int *lencopied, maxlength;
-	void *fromaddr, *toaddr; {
-	u_int tally;
-
-	tally = 0;
-	while (maxlength--) {
-		*(u_char *)toaddr = *(u_char *)fromaddr++;
-		tally++;
-		if (*(u_char *)toaddr++ == 0) {
-			if(lencopied) *lencopied = tally;
-			return(0);
-		}
-	}
-	if(lencopied) *lencopied = tally;
-	return(ENAMETOOLONG);
-}
-
-#endif
-
 #include "ddb.h"
 #if NDDB <= 0
 void
diff --git a/sys/amd64/amd64/mem.c b/sys/amd64/amd64/mem.c
index b9a912aa47dc..c3899a17c74f 100644
--- a/sys/amd64/amd64/mem.c
+++ b/sys/amd64/amd64/mem.c
@@ -38,7 +38,7 @@
  *
  *	from: Utah $Hdr: mem.c 1.13 89/10/08$
  *	from: @(#)mem.c	7.2 (Berkeley) 5/9/91
- *	$Id: mem.c,v 1.5 1993/11/25 01:30:59 wollman Exp $
+ *	$Id: mem.c,v 1.6 1993/12/19 00:50:06 wollman Exp $
  */
 
 /*
@@ -70,12 +70,12 @@ mmclose(dev, uio, flags)
 	struct uio *uio;
 	int flags;
 {
-	struct syscframe *fp;
+	struct trapframe *fp;
 
 	switch (minor(dev)) {
 	case 14:
-		fp = (struct syscframe *)curproc->p_regs;
-		fp->sf_eflags &= ~PSL_IOPL;
+		fp = (struct trapframe *)curproc->p_regs;
+		fp->tf_eflags &= ~PSL_IOPL;
 		break;
 	default:
 		break;
@@ -89,12 +89,12 @@ mmopen(dev, uio, flags)
 	struct uio *uio;
 	int flags;
 {
-	struct syscframe *fp;
+	struct trapframe *fp;
 
 	switch (minor(dev)) {
 	case 14:
-		fp = (struct syscframe *)curproc->p_regs;
-		fp->sf_eflags |= PSL_IOPL;
+		fp = (struct trapframe *)curproc->p_regs;
+		fp->tf_eflags |= PSL_IOPL;
 		break;
 	default:
 		break;
diff --git a/sys/amd64/amd64/trap.c b/sys/amd64/amd64/trap.c
index 41370cc46631..c85ac5786bd7 100644
--- a/sys/amd64/amd64/trap.c
+++ b/sys/amd64/amd64/trap.c
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)trap.c	7.4 (Berkeley) 5/13/91
- *	$Id: trap.c,v 1.11 1993/12/12 12:22:57 davidg Exp $
+ *	$Id: trap.c,v 1.12 1993/12/19 00:50:09 wollman Exp $
  */
 
 /*
@@ -179,7 +179,6 @@ if(curpcb == 0 || curproc == 0) goto we_re_toast;
 	if (ISPL(frame.tf_cs) == SEL_UPL) {
 		type |= T_USER;
 		p->p_regs = (int *)&frame;
-		curpcb->pcb_flags |= FM_TRAP;	/* used by sendsig */
 	}
 
 	ucode=0;
@@ -487,7 +486,6 @@ if(curpcb == 0 || curproc == 0) goto we_re_toast;
 		}
 	}
 	curpri = p->p_pri;
-	curpcb->pcb_flags &= ~FM_TRAP;	/* used by sendsig */
 }
 
 /*
@@ -575,7 +573,7 @@ int trapwrite(addr)
 /*ARGSUSED*/
 void
 syscall(frame)
-	volatile struct syscframe frame;
+	volatile struct trapframe frame;
 {
 	register int *locr0 = ((int *)&frame);
 	register caddr_t params;
@@ -591,29 +589,30 @@ syscall(frame)
 	r0 = 0; r0 = r0; r1 = 0; r1 = r1;
 #endif
 	syst = p->p_stime;
-	if (ISPL(frame.sf_cs) != SEL_UPL)
+	if (ISPL(frame.tf_cs) != SEL_UPL)
 		panic("syscall");
 
-	code = frame.sf_eax;
-	curpcb->pcb_flags &= ~FM_TRAP;	/* used by sendsig */
+	code = frame.tf_eax;
 	p->p_regs = (int *)&frame;
-	params = (caddr_t)frame.sf_esp + sizeof (int) ;
+	params = (caddr_t)frame.tf_esp + sizeof (int) ;
 
 	/*
 	 * Reconstruct pc, assuming lcall $X,y is 7 bytes, as it is always.
 	 */
-	opc = frame.sf_eip - 7;
-	callp = (code >= nsysent) ? &sysent[63] : &sysent[code];
-	if (callp == sysent) {
-		i = fuword(params);
+	opc = frame.tf_eip - 7;
+	if (code == 0) {
+		code = fuword(params);
 		params += sizeof (int);
-		callp = (code >= nsysent) ? &sysent[63] : &sysent[code];
 	}
+	if (code < 0 || code >= nsysent)
+		callp = &sysent[0];
+	else
+		callp = &sysent[code];
 
 	if ((i = callp->sy_narg * sizeof (int)) &&
 	    (error = copyin(params, (caddr_t)args, (u_int)i))) {
-		frame.sf_eax = error;
-		frame.sf_eflags |= PSL_C;	/* carry bit */
+		frame.tf_eax = error;
+		frame.tf_eflags |= PSL_C;	/* carry bit */
 #ifdef KTRACE
 		if (KTRPOINT(p, KTR_SYSCALL))
 			ktrsyscall(p->p_tracep, code, callp->sy_narg, args);
@@ -625,20 +624,20 @@ syscall(frame)
 		ktrsyscall(p->p_tracep, code, callp->sy_narg, args);
 #endif
 	rval[0] = 0;
-	rval[1] = frame.sf_edx;
+	rval[1] = frame.tf_edx;
 /*pg("%d. s %d\n", p->p_pid, code);*/
 	error = (*callp->sy_call)(p, args, rval);
 	if (error == ERESTART)
-		frame.sf_eip = opc;
+		frame.tf_eip = opc;
 	else if (error != EJUSTRETURN) {
 		if (error) {
 /*pg("error %d", error);*/
-			frame.sf_eax = error;
-			frame.sf_eflags |= PSL_C;	/* carry bit */
+			frame.tf_eax = error;
+			frame.tf_eflags |= PSL_C;	/* carry bit */
 		} else {
-			frame.sf_eax = rval[0];
-			frame.sf_edx = rval[1];
-			frame.sf_eflags &= ~PSL_C;	/* carry bit */
+			frame.tf_eax = rval[0];
+			frame.tf_edx = rval[1];
+			frame.tf_eflags &= ~PSL_C;	/* carry bit */
 		}
 	}
 	/* else if (error == EJUSTRETURN) */
@@ -679,10 +678,10 @@ syscall(frame)
 		if (ticks) {
 #ifdef PROFTIMER
 			extern int profscale;
-			addupc(frame.sf_eip, &p->p_stats->p_prof,
+			addupc(frame.tf_eip, &p->p_stats->p_prof,
 			    ticks * profscale);
 #else
-			addupc(frame.sf_eip, &p->p_stats->p_prof, ticks);
+			addupc(frame.tf_eip, &p->p_stats->p_prof, ticks);
 #endif
 		}
 	}
@@ -693,13 +692,13 @@ syscall(frame)
 #endif
 #ifdef	DIAGNOSTICx
 { extern int _udatasel, _ucodesel;
-	if (frame.sf_ss != _udatasel)
-		printf("ss %x call %d\n", frame.sf_ss, code);
-	if ((frame.sf_cs&0xffff) != _ucodesel)
-		printf("cs %x call %d\n", frame.sf_cs, code);
-	if (frame.sf_eip > VM_MAXUSER_ADDRESS) {
-		printf("eip %x call %d\n", frame.sf_eip, code);
-		frame.sf_eip = 0;
+	if (frame.tf_ss != _udatasel)
+		printf("ss %x call %d\n", frame.tf_ss, code);
+	if ((frame.tf_cs&0xffff) != _ucodesel)
+		printf("cs %x call %d\n", frame.tf_cs, code);
+	if (frame.tf_eip > VM_MAXUSER_ADDRESS) {
+		printf("eip %x call %d\n", frame.tf_eip, code);
+		frame.tf_eip = 0;
 	}
 }
 #endif
diff --git a/sys/amd64/include/frame.h b/sys/amd64/include/frame.h
index c61d17901d30..b36c141e7f83 100644
--- a/sys/amd64/include/frame.h
+++ b/sys/amd64/include/frame.h
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)frame.h	5.2 (Berkeley) 1/18/91
- *	$Id: frame.h,v 1.5 1993/12/03 05:10:00 alm Exp $
+ *	$Id: frame.h,v 1.6 1993/12/19 00:50:15 wollman Exp $
  */
 
 #ifndef _MACHINE_FRAME_H_
@@ -113,28 +113,5 @@ struct sigframe {
 	int	sf_edx;	
 	int	sf_ecx;	
 	struct	sigcontext sf_sc;
-} ;
-
-/*
- * Call Gate/System Call Stack Frame
- */
-
-struct syscframe {
-	int	sf_edi;
-	int	sf_esi;
-	int	sf_ebp;
-	int	:32;		/* redundant save of isp */
-	int	sf_ebx;
-	int	sf_edx;
-	int	sf_ecx;
-	int	sf_eax;
-	int	sf_eflags;
-	/* below portion defined in 386 hardware */
-/*	int	sf_args[N];*/ 	/* if call gate copy args enabled!*/
-	int	sf_eip;
-	int	sf_cs;
-	/* below only when transitting rings (e.g. user to kernel) */
-	int	sf_esp;
-	int	sf_ss;
 };
 #endif /* _MACHINE_FRAME_H_ */
diff --git a/sys/amd64/include/pcb.h b/sys/amd64/include/pcb.h
index 1090798ed926..a7a29dfdbb85 100644
--- a/sys/amd64/include/pcb.h
+++ b/sys/amd64/include/pcb.h
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)pcb.h	5.10 (Berkeley) 5/12/91
- *	$Id: pcb.h,v 1.2 1993/10/08 20:51:00 rgrimes Exp $
+ *	$Id: pcb.h,v 1.3 1993/11/07 17:42:59 wollman Exp $
  */
 
 #ifndef _I386_PCB_H_
@@ -72,7 +72,6 @@ struct pcb {
 #define	FP_NEEDSRESTORE	0x04	/* ... that needs restore on next DNA fault */
 #endif
 #define	FP_USESEMC	0x08	/* process uses EMC memory-mapped mode */
-#define	FM_TRAP		0x10	/* process entered kernel on a trap frame */
 #define	FP_SOFTFP	0x20	/* process using software fltng pnt emulator */
 	short	pcb_iml;	/* interrupt mask level */
 	caddr_t	pcb_onfault;	/* copyin/out fault recovery */
diff --git a/sys/amd64/include/reg.h b/sys/amd64/include/reg.h
index 969df8782289..4cefae0e1305 100644
--- a/sys/amd64/include/reg.h
+++ b/sys/amd64/include/reg.h
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)reg.h	5.5 (Berkeley) 1/18/91
- *	$Id: reg.h,v 1.4 1993/11/16 09:54:57 davidg Exp $
+ *	$Id: reg.h,v 1.5 1993/12/03 05:10:08 alm Exp $
  */
 
 #ifndef _MACHINE_REG_H_
@@ -68,28 +68,6 @@
 #define	tESP	(15)
 #define	tSS	(16)
 
-/* During a system call, registers are at these offsets instead of above. */
-
-#define	sEDI	(0)
-#define	sESI	(1)
-#define	sEBP	(2)
-
-#define	sEBX	(4)
-#define	sEDX	(5)
-#define	sECX	(6)
-#define	sEAX	(7)
-#define	sEFLAGS	(8)
-#define	sEIP	(9)
-#define	sCS	(10)
-#define	sESP	(11)
-#define	sSS	(12)
-
-#define PC	sEIP
-#define SP	sESP
-#define PS	sEFLAGS
-#define R0	sEDX
-#define R1	sECX
-
 /*
  * Registers accessible to ptrace(2) syscall for debugger
  * The machine-dependent code for PT_{SET,GET}REGS needs to
diff --git a/sys/amd64/isa/npx.c b/sys/amd64/isa/npx.c
index 0e90bff2433f..796dfbbae406 100644
--- a/sys/amd64/isa/npx.c
+++ b/sys/amd64/isa/npx.c
@@ -32,7 +32,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)npx.c	7.2 (Berkeley) 5/12/91
- *	$Id: npx.c,v 1.4 1993/11/03 00:29:19 paul Exp $
+ *	$Id: npx.c,v 1.5 1993/11/03 23:32:35 paul Exp $
  */
 
 #include "npx.h"
@@ -439,7 +439,6 @@ npxintr(frame)
 		 * just before it is used).
 		 */
 		curproc->p_regs = (int *)&frame.if_es;
-		curpcb->pcb_flags |= FM_TRAP;	/* used by sendsig */
 #ifdef notyet
 		/*
 		 * Encode the appropriate code for detailed information on
@@ -450,7 +449,6 @@ npxintr(frame)
 		code = 0;	/* XXX */
 #endif
 		trapsignal(curproc, SIGFPE, code);
-		curpcb->pcb_flags &= ~FM_TRAP;
 	} else {
 		/*
 		 * Nested interrupt.  These losers occur when:
diff --git a/sys/dev/syscons/syscons.c b/sys/dev/syscons/syscons.c
index b683ea02d0f9..f8c87632aae7 100644
--- a/sys/dev/syscons/syscons.c
+++ b/sys/dev/syscons/syscons.c
@@ -35,7 +35,7 @@
  *
  *	from: @(#)pccons.c	5.11 (Berkeley) 5/21/91
  *	from: @(#)syscons.c	1.1 931021
- *	$Id: syscons.c,v 1.22 1993/12/21 02:49:13 rich Exp $
+ *	$Id: syscons.c,v 1.23 1993/12/21 03:27:26 rich Exp $
  *
  * Heavily modified by Søren Schmidt (sos@login.dkuug.dk) to provide:
  *
@@ -526,14 +526,8 @@ pcparam(struct tty *tp, struct termios *t)
 	return(0);
 }
 
-
-#if defined(NetBSD)
 #define	frametype	struct trapframe 
 #define eflags		tf_eflags
-#else
-#define	frametype	struct syscframe
-#define eflags		sf_eflags
-#endif
 
 int
 pcioctl(dev_t dev, int cmd, caddr_t data, int flag, struct proc *p)
diff --git a/sys/i386/i386/db_trace.c b/sys/i386/i386/db_trace.c
index 9e300cf2ec7d..5e475a4a1c55 100644
--- a/sys/i386/i386/db_trace.c
+++ b/sys/i386/i386/db_trace.c
@@ -23,7 +23,7 @@
  * any improvements or extensions that they make and grant Carnegie the
  * rights to redistribute these changes.
  *
- *	$Id: db_trace.c,v 1.2 1993/10/16 14:14:56 rgrimes Exp $
+ *	$Id: db_trace.c,v 1.3 1993/12/19 00:50:01 wollman Exp $
  */
 
 #include "param.h"
@@ -73,8 +73,10 @@ struct i386_frame {
 
 #define	TRAP		1
 #define	INTERRUPT	2
+#define	SYSCALL		3
 
 db_addr_t	db_trap_symbol_value = 0;
+db_addr_t	db_syscall_symbol_value = 0;
 db_addr_t	db_kdintr_symbol_value = 0;
 boolean_t	db_trace_symbols_found = FALSE;
 
@@ -86,6 +88,8 @@ db_find_trace_symbols()
 	    db_trap_symbol_value = (db_addr_t) value;
 	if (db_value_of_name("_kdintr", &value))
 	    db_kdintr_symbol_value = (db_addr_t) value;
+	if (db_value_of_name("_syscall", &value))
+	    db_syscall_symbol_value = (db_addr_t) value;
 	db_trace_symbols_found = TRUE;
 }
 
@@ -135,26 +139,43 @@ db_nextframe(fp, ip, argp, is_trap)
 {
 	struct i386_saved_state *saved_regs;
 
-	if (is_trap == 0) {
+	switch (is_trap) {
+	case 0:
 	    *ip = (db_addr_t)
 			db_get_value((int) &(*fp)->f_retaddr, 4, FALSE);
 	    *fp = (struct i386_frame *)
 			db_get_value((int) &(*fp)->f_frame, 4, FALSE);
-	} else {
+	    break;
+	case TRAP:
+	default:
 	    /*
 	     * We know that trap() has 1 argument and we know that
 	     * it is an (int *).
 	     */
+#if 0
 	    saved_regs = (struct i386_saved_state *)
 			db_get_value((int)argp, 4, FALSE);
+#endif
+	    saved_regs = (struct i386_saved_state *)argp;
 	    db_printf("--- trap (number %d) ---\n",
 		      saved_regs->tf_trapno & 0xffff);
 	    db_printsym(saved_regs->tf_eip, DB_STGY_XTRN);
 	    db_printf(":\n");
 	    *fp = (struct i386_frame *)saved_regs->tf_ebp;
 	    *ip = (db_addr_t)saved_regs->tf_eip;
-	}
+	    break;
 
+	case SYSCALL: {
+	    struct trapframe	*saved_regs = (struct trapframe *)argp;
+
+	    db_printf("--- syscall (number %d) ---\n", saved_regs->tf_eax);
+	    db_printsym(saved_regs->tf_eip, DB_STGY_XTRN);
+	    db_printf(":\n");
+	    *fp = (struct i386_frame *)saved_regs->tf_ebp;
+	    *ip = (db_addr_t)saved_regs->tf_eip;
+	    }
+	    break;
+	}
 }
 
 void
@@ -171,8 +192,10 @@ db_stack_trace_cmd(addr, have_addr, count, modif)
 	boolean_t	kernel_only = TRUE;
 	boolean_t	trace_thread = FALSE;
 
+#if 0
 	if (!db_trace_symbols_found)
 	    db_find_trace_symbols();
+#endif
 
 	{
 	    register char *cp = modif;
@@ -203,38 +226,84 @@ db_stack_trace_cmd(addr, have_addr, count, modif)
 
 	lastframe = 0;
 	while (count-- && frame != 0) {
-	    register int narg;
+	    int		narg;
 	    char *	name;
 	    db_expr_t	offset;
+	    db_sym_t	sym;
+#define MAXNARG	16
+	    char	*argnames[MAXNARG], **argnp = NULL;
 
-	    if (INKERNEL((int)frame) && callpc == db_trap_symbol_value) {
+	    sym = db_search_symbol(callpc, DB_STGY_ANY, &offset);
+	    db_symbol_values(sym, &name, NULL);
+
+	    if (lastframe == 0 && sym == NULL) {
+		/* Symbol not found, peek at code */
+		int	instr = db_get_value(callpc, 4, FALSE);
+
+		offset = 1;
+		if ((instr & 0x00ffffff) == 0x00e58955 ||
+				/* enter: pushl %ebp, movl %esp, %ebp */
+			(instr & 0x0000ffff) == 0x0000e589
+				/* enter+1: movl %esp, %ebp */	) {
+			offset = 0;
+		}
+	    }
+#define STRCMP(s1,s2) ((s1) && (s2) && strcmp((s1), (s2)) == 0)
+	    if (INKERNEL((int)frame) && STRCMP(name, "_trap")) {
 		narg = 1;
 		is_trap = TRAP;
 	    }
 	    else
-	    if (INKERNEL((int)frame) && callpc == db_kdintr_symbol_value) {
+	    if (INKERNEL((int)frame) && STRCMP(name, "_kdintr")) {
 		is_trap = INTERRUPT;
 		narg = 0;
 	    }
+	    else
+	    if (INKERNEL((int)frame) && STRCMP(name, "_syscall")) {
+		is_trap = SYSCALL;
+		narg = 0;
+	    }
+#undef STRCMP
 	    else {
 		is_trap = 0;
-		narg = db_numargs(frame);
+		narg = MAXNARG;
+		if (db_sym_numargs(sym, &narg, argnames)) {
+			argnp = argnames;
+		} else {
+			narg = db_numargs(frame);
+		}
 	    }
 
-	    db_find_sym_and_offset(callpc, &name, &offset);
 	    db_printf("%s(", name);
 
-	    argp = &frame->f_arg0;
+	    if (lastframe == 0 && offset == 0 && !have_addr) {
+		/*
+		 * We have a breakpoint before the frame is set up
+		 * Use %esp instead
+		 */
+		argp = &((struct i386_frame *)(ddb_regs.tf_esp-4))->f_arg0;
+	    } else
+		argp = &frame->f_arg0;
+
 	    while (narg) {
+		if (argnp)
+			db_printf("%s=", *argnp++);
 		db_printf("%x", db_get_value((int)argp, 4, FALSE));
 		argp++;
 		if (--narg != 0)
 		    db_printf(",");
 	    }
 	    db_printf(") at ");
-	    db_printsym(callpc, DB_STGY_XTRN);
+	    db_printsym(callpc, DB_STGY_PROC);
 	    db_printf("\n");
 
+	    if (lastframe == 0 && offset == 0 && !have_addr) {
+		/* Frame really belongs to next callpc */
+		lastframe = (struct i386_frame *)(ddb_regs.tf_esp-4);
+		callpc = (db_addr_t)db_get_value((int)&lastframe->f_retaddr, 4, FALSE);
+		continue;
+	    }
+
 	    lastframe = frame;
 	    db_nextframe(&frame, &callpc, &frame->f_arg0, is_trap);
 
@@ -257,7 +326,7 @@ db_stack_trace_cmd(addr, have_addr, count, modif)
 	    else {
 		/* in user */
 		if (frame <= lastframe) {
-		    db_printf("Bad frame pointer: 0x%x\n", frame);
+		    db_printf("Bad user frame pointer: 0x%x\n", frame);
 		    break;
 		}
 	    }
diff --git a/sys/i386/i386/exception.s b/sys/i386/i386/exception.s
index d6de8748a5cb..93aed946f655 100644
--- a/sys/i386/i386/exception.s
+++ b/sys/i386/i386/exception.s
@@ -30,7 +30,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- *	$Id$
+ *	$Id: exception.s,v 1.1 1993/11/13 02:24:57 davidg Exp $
  */
 
 #include "npx.h"				/* NNPX */
@@ -181,7 +181,7 @@ calltrap:
 	 * Return through doreti to handle ASTs.  Have to change trap frame
 	 * to interrupt frame.
 	 */
-	movl	$T_ASTFLT,4+4+32(%esp)		/* new trap type (err code not used) */
+	movl	$T_ASTFLT,TF_TRAPNO(%esp)	/* new trap type (err code not used) */
 	pushl	_cpl
 	pushl	$0				/* dummy unit */
 	jmp	doreti
@@ -195,8 +195,8 @@ calltrap:
 bpttraps:
 	pushal
 	nop
-	pushl	%es
 	pushl	%ds
+	pushl	%es
 	movl	$KDSEL,%eax
 	movl	%ax,%ds
 	movl	%ax,%es
@@ -211,38 +211,24 @@ bpttraps:
  */
 	SUPERALIGN_TEXT
 IDTVEC(syscall)
-	pushfl	/* only for stupid carry bit and more stupid wait3 cc kludge */
-		/* XXX - also for direction flag (bzero, etc. clear it) */
-	pushal	/* only need eax,ecx,edx - trap resaves others */
+	pushfl					/* Room for tf_err */
+	pushfl					/* Room for tf_trapno */
+	pushal
 	nop
+	pushl	%ds
+	pushl	%es
 	movl	$KDSEL,%eax			/* switch to kernel segments */
 	movl	%ax,%ds
 	movl	%ax,%es
+	movl	TF_ERR(%esp),%eax		/* copy eflags from tf_err to fs_eflags */
+	movl	%eax,TF_EFLAGS(%esp)
+	movl	$0,TF_ERR(%esp)			/* zero tf_err */
 	incl	_cnt+V_SYSCALL
 	call	_syscall
 	/*
-	 * Return through doreti to handle ASTs.  Have to change syscall frame
-	 * to interrupt frame.
-	 *
-	 * XXX - we should have set up the frame earlier to avoid the
-	 * following popal/pushal (not much can be done to avoid shuffling
-	 * the flags).  Consistent frames would simplify things all over.
+	 * Return through doreti to handle ASTs.
 	 */
-	movl	32+0(%esp),%eax			/* old flags, shuffle to above cs:eip */
-	movl	32+4(%esp),%ebx			/* `int' frame should have been ef, eip, cs */
-	movl	32+8(%esp),%ecx
-	movl	%ebx,32+0(%esp)
-	movl	%ecx,32+4(%esp)
-	movl	%eax,32+8(%esp)
-	popal
-	nop
-	pushl	$0				/* dummy error code */
-	pushl	$T_ASTFLT
-	pushal
-	nop
-	movl	__udatasel,%eax			/* switch back to user segments */
-	pushl	%eax				/* XXX - better to preserve originals? */
-	pushl	%eax
+	movl	$T_ASTFLT,TF_TRAPNO(%esp)	/* new trap type (err code not used) */
 	pushl	_cpl
 	pushl	$0
 	jmp	doreti
diff --git a/sys/i386/i386/machdep.c b/sys/i386/i386/machdep.c
index 417147462779..f47d9e62ed47 100644
--- a/sys/i386/i386/machdep.c
+++ b/sys/i386/i386/machdep.c
@@ -35,7 +35,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)machdep.c	7.4 (Berkeley) 6/3/91
- *	$Id: machdep.c,v 1.22 1993/12/19 00:50:03 wollman Exp $
+ *	$Id: machdep.c,v 1.23 1993/12/22 13:12:04 davidg Exp $
  */
 
 #include "npx.h"
@@ -418,7 +418,6 @@ sendsig(catcher, sig, mask, code)
 
 	regs = p->p_regs;
         oonstack = ps->ps_onstack;
-	frmtrap = curpcb->pcb_flags & FM_TRAP;
 	/*
 	 * Allocate and validate space for the signal handler
 	 * context. Note that if the stack is in P0 space, the
@@ -431,12 +430,8 @@ sendsig(catcher, sig, mask, code)
 				- sizeof(struct sigframe));
                 ps->ps_onstack = 1;
 	} else {
-		if (frmtrap)
-			fp = (struct sigframe *)(regs[tESP]
-				- sizeof(struct sigframe));
-		else
-			fp = (struct sigframe *)(regs[sESP]
-				- sizeof(struct sigframe));
+		fp = (struct sigframe *)(regs[tESP]
+			- sizeof(struct sigframe));
 	}
 
 	if (useracc((caddr_t)fp, sizeof (struct sigframe), B_WRITE) == 0) {
@@ -463,35 +458,21 @@ sendsig(catcher, sig, mask, code)
 	fp->sf_handler = catcher;
 
 	/* save scratch registers */
-	if(frmtrap) {
-		fp->sf_eax = regs[tEAX];
-		fp->sf_edx = regs[tEDX];
-		fp->sf_ecx = regs[tECX];
-	} else {
-		fp->sf_eax = regs[sEAX];
-		fp->sf_edx = regs[sEDX];
-		fp->sf_ecx = regs[sECX];
-	}
+	fp->sf_eax = regs[tEAX];
+	fp->sf_edx = regs[tEDX];
+	fp->sf_ecx = regs[tECX];
+
 	/*
 	 * Build the signal context to be used by sigreturn.
 	 */
 	fp->sf_sc.sc_onstack = oonstack;
 	fp->sf_sc.sc_mask = mask;
-	if(frmtrap) {
-		fp->sf_sc.sc_sp = regs[tESP];
-		fp->sf_sc.sc_fp = regs[tEBP];
-		fp->sf_sc.sc_pc = regs[tEIP];
-		fp->sf_sc.sc_ps = regs[tEFLAGS];
-		regs[tESP] = (int)fp;
-		regs[tEIP] = (int)((struct pcb *)kstack)->pcb_sigc;
-	} else {
-		fp->sf_sc.sc_sp = regs[sESP];
-		fp->sf_sc.sc_fp = regs[sEBP];
-		fp->sf_sc.sc_pc = regs[sEIP];
-		fp->sf_sc.sc_ps = regs[sEFLAGS];
-		regs[sESP] = (int)fp;
-		regs[sEIP] = (int)((struct pcb *)kstack)->pcb_sigc;
-	}
+	fp->sf_sc.sc_sp = regs[tESP];
+	fp->sf_sc.sc_fp = regs[tEBP];
+	fp->sf_sc.sc_pc = regs[tEIP];
+	fp->sf_sc.sc_ps = regs[tEFLAGS];
+	regs[tESP] = (int)fp;
+	regs[tEIP] = (int)((struct pcb *)kstack)->pcb_sigc;
 }
 
 /*
@@ -519,7 +500,7 @@ sigreturn(p, uap, retval)
 	register int *regs = p->p_regs;
 
 	/*
-	 * (XXX old comment) regs[sESP] points to the return address.
+	 * (XXX old comment) regs[tESP] points to the return address.
 	 * The user scp pointer is above that.
 	 * The return address is faked in the signal trampoline code
 	 * for consistency.
@@ -532,9 +513,9 @@ sigreturn(p, uap, retval)
 		return(EINVAL);
 
 	/* restore scratch registers */
-	regs[sEAX] = fp->sf_eax ;
-	regs[sEDX] = fp->sf_edx ;
-	regs[sECX] = fp->sf_ecx ;
+	regs[tEAX] = fp->sf_eax ;
+	regs[tEDX] = fp->sf_edx ;
+	regs[tECX] = fp->sf_ecx ;
 
 	if (useracc((caddr_t)scp, sizeof (*scp), 0) == 0)
 		return(EINVAL);
@@ -546,10 +527,10 @@ sigreturn(p, uap, retval)
         p->p_sigacts->ps_onstack = scp->sc_onstack & 01;
 	p->p_sigmask = scp->sc_mask &~
 	    (sigmask(SIGKILL)|sigmask(SIGCONT)|sigmask(SIGSTOP));
-	regs[sEBP] = scp->sc_fp;
-	regs[sESP] = scp->sc_sp;
-	regs[sEIP] = scp->sc_pc;
-	regs[sEFLAGS] = scp->sc_ps;
+	regs[tEBP] = scp->sc_fp;
+	regs[tESP] = scp->sc_sp;
+	regs[tEIP] = scp->sc_pc;
+	regs[tEFLAGS] = scp->sc_ps;
 	return(EJUSTRETURN);
 }
 
@@ -762,13 +743,18 @@ initcpu()
  * Clear registers on exec
  */
 void
-setregs(p, entry)
+setregs(p, entry, stack)
 	struct proc *p;
 	u_long entry;
+	u_long stack;
 {
-
-	p->p_regs[sEBP] = 0;	/* bottom of the fp chain */
-	p->p_regs[sEIP] = entry;
+	p->p_regs[tEBP] = 0;	/* bottom of the fp chain */
+	p->p_regs[tEIP] = entry;
+	p->p_regs[tESP] = stack;
+	p->p_regs[tSS] = _udatasel;
+	p->p_regs[tDS] = _udatasel;
+	p->p_regs[tES] = _udatasel;
+	p->p_regs[tCS] = _ucodesel;
 
 	p->p_addr->u_pcb.pcb_flags = 0;	/* no fp at all */
 	load_cr0(rcr0() | CR0_TS);	/* start emulating */
@@ -1153,7 +1139,7 @@ init386(first)
 	x = (int) &IDTVEC(syscall);
 	gdp->gd_looffset = x++;
 	gdp->gd_selector = GSEL(GCODE_SEL,SEL_KPL);
-	gdp->gd_stkcpy = 0;
+	gdp->gd_stkcpy = 1;	/* Leaves room for eflags like a trap */
 	gdp->gd_type = SDT_SYS386CGT;
 	gdp->gd_dpl = SEL_UPL;
 	gdp->gd_p = 1;
@@ -1268,35 +1254,24 @@ _remque(element)
 
 int
 ptrace_set_pc (struct proc *p, unsigned int addr) {
-	struct pcb *pcb;
 	void *regs = (char*)p->p_addr +
 		((char*) p->p_regs - (char*) kstack);
 
-	pcb = &p->p_addr->u_pcb;
-	if (pcb->pcb_flags & FM_TRAP)
-		((struct trapframe *)regs)->tf_eip = addr;
-	else
-		((struct syscframe *)regs)->sf_eip = addr;
+	((struct trapframe *)regs)->tf_eip = addr;
 	return 0;
 }
 
 int
 ptrace_single_step (struct proc *p) {
-	struct pcb *pcb;
 	void *regs = (char*)p->p_addr +
 		((char*) p->p_regs - (char*) kstack);
 
-	pcb = &p->p_addr->u_pcb;
-	if (pcb->pcb_flags & FM_TRAP)
-		((struct trapframe *)regs)->tf_eflags |= PSL_T;
-	else
-		((struct syscframe *)regs)->sf_eflags |= PSL_T;
+	((struct trapframe *)regs)->tf_eflags |= PSL_T;
 	return 0;
 }
 
 /*
- * Copy the registers to user-space.  This is tedious because
- * we essentially duplicate code for trapframe and syscframe. *sigh*
+ * Copy the registers to user-space.
  */
 
 int
@@ -1325,50 +1300,24 @@ int
 fill_regs(struct proc *p, struct regs *regs) {
 	int error;
 	struct trapframe *tp;
-	struct syscframe *sp;
-	struct pcb *pcb;
 	void *ptr = (char*)p->p_addr +
 		((char*) p->p_regs - (char*) kstack);
 
-	pcb = &p->p_addr->u_pcb;
-	if (pcb->pcb_flags & FM_TRAP) {
-		tp = ptr;
-		regs->r_es = tp->tf_es;
-		regs->r_ds = tp->tf_ds;
-		regs->r_edi = tp->tf_edi;
-		regs->r_esi = tp->tf_esi;
-		regs->r_ebp = tp->tf_ebp;
-		regs->r_ebx = tp->tf_ebx;
-		regs->r_edx = tp->tf_edx;
-		regs->r_ecx = tp->tf_ecx;
-		regs->r_eax = tp->tf_eax;
-		regs->r_eip = tp->tf_eip;
-		regs->r_cs = tp->tf_cs;
-		regs->r_eflags = tp->tf_eflags;
-		regs->r_esp = tp->tf_esp;
-		regs->r_ss = tp->tf_ss;
-	} else {
-		sp = ptr;
-		/*
-		 * No sf_es or sf_ds... dunno why.
-		 */
-		/*
-		 * regs.r_es = sp->sf_es;
-		 * regs.r_ds = sp->sf_ds;
-		 */
-		regs->r_edi = sp->sf_edi;
-		regs->r_esi = sp->sf_esi;
-		regs->r_ebp = sp->sf_ebp;
-		regs->r_ebx = sp->sf_ebx;
-		regs->r_edx = sp->sf_edx;
-		regs->r_ecx = sp->sf_ecx;
-		regs->r_eax = sp->sf_eax;
-		regs->r_eip = sp->sf_eip;
-		regs->r_cs = sp->sf_cs;
-		regs->r_eflags = sp->sf_eflags;
-		regs->r_esp = sp->sf_esp;
-		regs->r_ss = sp->sf_ss;
-	}
+	tp = ptr;
+	regs->r_es = tp->tf_es;
+	regs->r_ds = tp->tf_ds;
+	regs->r_edi = tp->tf_edi;
+	regs->r_esi = tp->tf_esi;
+	regs->r_ebp = tp->tf_ebp;
+	regs->r_ebx = tp->tf_ebx;
+	regs->r_edx = tp->tf_edx;
+	regs->r_ecx = tp->tf_ecx;
+	regs->r_eax = tp->tf_eax;
+	regs->r_eip = tp->tf_eip;
+	regs->r_cs = tp->tf_cs;
+	regs->r_eflags = tp->tf_eflags;
+	regs->r_esp = tp->tf_esp;
+	regs->r_ss = tp->tf_ss;
 	return 0;
 }
 
@@ -1376,122 +1325,27 @@ int
 set_regs (struct proc *p, struct regs *regs) {
 	int error;
 	struct trapframe *tp;
-	struct syscframe *sp;
-	struct pcb *pcb;
 	void *ptr = (char*)p->p_addr +
 		((char*) p->p_regs - (char*) kstack);
 
-	pcb = &p->p_addr->u_pcb;
-	if (pcb->pcb_flags & FM_TRAP) {
-		tp = ptr;
-		tp->tf_es = regs->r_es;
-		tp->tf_ds = regs->r_ds;
-		tp->tf_edi = regs->r_edi;
-		tp->tf_esi = regs->r_esi;
-		tp->tf_ebp = regs->r_ebp;
-		tp->tf_ebx = regs->r_ebx;
-		tp->tf_edx = regs->r_edx;
-		tp->tf_ecx = regs->r_ecx;
-		tp->tf_eax = regs->r_eax;
-		tp->tf_eip = regs->r_eip;
-		tp->tf_cs = regs->r_cs;
-		tp->tf_eflags = regs->r_eflags;
-		tp->tf_esp = regs->r_esp;
-		tp->tf_ss = regs->r_ss;
-	} else {
-		sp = ptr;
-		/*
-		 * No sf_es or sf_ds members, dunno why...
-		 */
-		/*
-		 * sp->sf_es = regs.r_es;
-		 * sp->sf_ds = regs.r_ds;
-		 */
-		sp->sf_edi = regs->r_edi;
-		sp->sf_esi = regs->r_esi;
-		sp->sf_ebp = regs->r_ebp;
-		sp->sf_ebx = regs->r_ebx;
-		sp->sf_edx = regs->r_edx;
-		sp->sf_ecx = regs->r_ecx;
-		sp->sf_eax = regs->r_eax;
-		sp->sf_eip = regs->r_eip;
-		sp->sf_cs = regs->r_cs;
-		sp->sf_eflags = regs->r_eflags;
-		sp->sf_esp = regs->r_esp;
-		sp->sf_ss = regs->r_ss;
-	}
+	tp = ptr;
+	tp->tf_es = regs->r_es;
+	tp->tf_ds = regs->r_ds;
+	tp->tf_edi = regs->r_edi;
+	tp->tf_esi = regs->r_esi;
+	tp->tf_ebp = regs->r_ebp;
+	tp->tf_ebx = regs->r_ebx;
+	tp->tf_edx = regs->r_edx;
+	tp->tf_ecx = regs->r_ecx;
+	tp->tf_eax = regs->r_eax;
+	tp->tf_eip = regs->r_eip;
+	tp->tf_cs = regs->r_cs;
+	tp->tf_eflags = regs->r_eflags;
+	tp->tf_esp = regs->r_esp;
+	tp->tf_ss = regs->r_ss;
 	return 0;
 }
 
-#ifdef SLOW_OLD_COPYSTRS
-vmunaccess() {}
-
-#if 0		/* assembler versions now in locore.s */
-/*
- * Below written in C to allow access to debugging code
- */
-copyinstr(fromaddr, toaddr, maxlength, lencopied) u_int *lencopied, maxlength;
-	void *toaddr, *fromaddr; {
-	int c,tally;
-
-	tally = 0;
-	while (maxlength--) {
-		c = fubyte(fromaddr++);
-		if (c == -1) {
-			if(lencopied) *lencopied = tally;
-			return(EFAULT);
-		}
-		tally++;
-		*(char *)toaddr++ = (char) c;
-		if (c == 0){
-			if(lencopied) *lencopied = (u_int)tally;
-			return(0);
-		}
-	}
-	if(lencopied) *lencopied = (u_int)tally;
-	return(ENAMETOOLONG);
-}
-
-copyoutstr(fromaddr, toaddr, maxlength, lencopied) u_int *lencopied, maxlength;
-	void *fromaddr, *toaddr; {
-	int c;
-	int tally;
-
-	tally = 0;
-	while (maxlength--) {
-		c = subyte(toaddr++, *(char *)fromaddr);
-		if (c == -1) return(EFAULT);
-		tally++;
-		if (*(char *)fromaddr++ == 0){
-			if(lencopied) *lencopied = tally;
-			return(0);
-		}
-	}
-	if(lencopied) *lencopied = tally;
-	return(ENAMETOOLONG);
-}
-
-#endif /* SLOW_OLD_COPYSTRS */
-
-copystr(fromaddr, toaddr, maxlength, lencopied) u_int *lencopied, maxlength;
-	void *fromaddr, *toaddr; {
-	u_int tally;
-
-	tally = 0;
-	while (maxlength--) {
-		*(u_char *)toaddr = *(u_char *)fromaddr++;
-		tally++;
-		if (*(u_char *)toaddr++ == 0) {
-			if(lencopied) *lencopied = tally;
-			return(0);
-		}
-	}
-	if(lencopied) *lencopied = tally;
-	return(ENAMETOOLONG);
-}
-
-#endif
-
 #include "ddb.h"
 #if NDDB <= 0
 void
diff --git a/sys/i386/i386/mem.c b/sys/i386/i386/mem.c
index b9a912aa47dc..c3899a17c74f 100644
--- a/sys/i386/i386/mem.c
+++ b/sys/i386/i386/mem.c
@@ -38,7 +38,7 @@
  *
  *	from: Utah $Hdr: mem.c 1.13 89/10/08$
  *	from: @(#)mem.c	7.2 (Berkeley) 5/9/91
- *	$Id: mem.c,v 1.5 1993/11/25 01:30:59 wollman Exp $
+ *	$Id: mem.c,v 1.6 1993/12/19 00:50:06 wollman Exp $
  */
 
 /*
@@ -70,12 +70,12 @@ mmclose(dev, uio, flags)
 	struct uio *uio;
 	int flags;
 {
-	struct syscframe *fp;
+	struct trapframe *fp;
 
 	switch (minor(dev)) {
 	case 14:
-		fp = (struct syscframe *)curproc->p_regs;
-		fp->sf_eflags &= ~PSL_IOPL;
+		fp = (struct trapframe *)curproc->p_regs;
+		fp->tf_eflags &= ~PSL_IOPL;
 		break;
 	default:
 		break;
@@ -89,12 +89,12 @@ mmopen(dev, uio, flags)
 	struct uio *uio;
 	int flags;
 {
-	struct syscframe *fp;
+	struct trapframe *fp;
 
 	switch (minor(dev)) {
 	case 14:
-		fp = (struct syscframe *)curproc->p_regs;
-		fp->sf_eflags |= PSL_IOPL;
+		fp = (struct trapframe *)curproc->p_regs;
+		fp->tf_eflags |= PSL_IOPL;
 		break;
 	default:
 		break;
diff --git a/sys/i386/i386/trap.c b/sys/i386/i386/trap.c
index 41370cc46631..c85ac5786bd7 100644
--- a/sys/i386/i386/trap.c
+++ b/sys/i386/i386/trap.c
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)trap.c	7.4 (Berkeley) 5/13/91
- *	$Id: trap.c,v 1.11 1993/12/12 12:22:57 davidg Exp $
+ *	$Id: trap.c,v 1.12 1993/12/19 00:50:09 wollman Exp $
  */
 
 /*
@@ -179,7 +179,6 @@ if(curpcb == 0 || curproc == 0) goto we_re_toast;
 	if (ISPL(frame.tf_cs) == SEL_UPL) {
 		type |= T_USER;
 		p->p_regs = (int *)&frame;
-		curpcb->pcb_flags |= FM_TRAP;	/* used by sendsig */
 	}
 
 	ucode=0;
@@ -487,7 +486,6 @@ if(curpcb == 0 || curproc == 0) goto we_re_toast;
 		}
 	}
 	curpri = p->p_pri;
-	curpcb->pcb_flags &= ~FM_TRAP;	/* used by sendsig */
 }
 
 /*
@@ -575,7 +573,7 @@ int trapwrite(addr)
 /*ARGSUSED*/
 void
 syscall(frame)
-	volatile struct syscframe frame;
+	volatile struct trapframe frame;
 {
 	register int *locr0 = ((int *)&frame);
 	register caddr_t params;
@@ -591,29 +589,30 @@ syscall(frame)
 	r0 = 0; r0 = r0; r1 = 0; r1 = r1;
 #endif
 	syst = p->p_stime;
-	if (ISPL(frame.sf_cs) != SEL_UPL)
+	if (ISPL(frame.tf_cs) != SEL_UPL)
 		panic("syscall");
 
-	code = frame.sf_eax;
-	curpcb->pcb_flags &= ~FM_TRAP;	/* used by sendsig */
+	code = frame.tf_eax;
 	p->p_regs = (int *)&frame;
-	params = (caddr_t)frame.sf_esp + sizeof (int) ;
+	params = (caddr_t)frame.tf_esp + sizeof (int) ;
 
 	/*
 	 * Reconstruct pc, assuming lcall $X,y is 7 bytes, as it is always.
 	 */
-	opc = frame.sf_eip - 7;
-	callp = (code >= nsysent) ? &sysent[63] : &sysent[code];
-	if (callp == sysent) {
-		i = fuword(params);
+	opc = frame.tf_eip - 7;
+	if (code == 0) {
+		code = fuword(params);
 		params += sizeof (int);
-		callp = (code >= nsysent) ? &sysent[63] : &sysent[code];
 	}
+	if (code < 0 || code >= nsysent)
+		callp = &sysent[0];
+	else
+		callp = &sysent[code];
 
 	if ((i = callp->sy_narg * sizeof (int)) &&
 	    (error = copyin(params, (caddr_t)args, (u_int)i))) {
-		frame.sf_eax = error;
-		frame.sf_eflags |= PSL_C;	/* carry bit */
+		frame.tf_eax = error;
+		frame.tf_eflags |= PSL_C;	/* carry bit */
 #ifdef KTRACE
 		if (KTRPOINT(p, KTR_SYSCALL))
 			ktrsyscall(p->p_tracep, code, callp->sy_narg, args);
@@ -625,20 +624,20 @@ syscall(frame)
 		ktrsyscall(p->p_tracep, code, callp->sy_narg, args);
 #endif
 	rval[0] = 0;
-	rval[1] = frame.sf_edx;
+	rval[1] = frame.tf_edx;
 /*pg("%d. s %d\n", p->p_pid, code);*/
 	error = (*callp->sy_call)(p, args, rval);
 	if (error == ERESTART)
-		frame.sf_eip = opc;
+		frame.tf_eip = opc;
 	else if (error != EJUSTRETURN) {
 		if (error) {
 /*pg("error %d", error);*/
-			frame.sf_eax = error;
-			frame.sf_eflags |= PSL_C;	/* carry bit */
+			frame.tf_eax = error;
+			frame.tf_eflags |= PSL_C;	/* carry bit */
 		} else {
-			frame.sf_eax = rval[0];
-			frame.sf_edx = rval[1];
-			frame.sf_eflags &= ~PSL_C;	/* carry bit */
+			frame.tf_eax = rval[0];
+			frame.tf_edx = rval[1];
+			frame.tf_eflags &= ~PSL_C;	/* carry bit */
 		}
 	}
 	/* else if (error == EJUSTRETURN) */
@@ -679,10 +678,10 @@ syscall(frame)
 		if (ticks) {
 #ifdef PROFTIMER
 			extern int profscale;
-			addupc(frame.sf_eip, &p->p_stats->p_prof,
+			addupc(frame.tf_eip, &p->p_stats->p_prof,
 			    ticks * profscale);
 #else
-			addupc(frame.sf_eip, &p->p_stats->p_prof, ticks);
+			addupc(frame.tf_eip, &p->p_stats->p_prof, ticks);
 #endif
 		}
 	}
@@ -693,13 +692,13 @@ syscall(frame)
 #endif
 #ifdef	DIAGNOSTICx
 { extern int _udatasel, _ucodesel;
-	if (frame.sf_ss != _udatasel)
-		printf("ss %x call %d\n", frame.sf_ss, code);
-	if ((frame.sf_cs&0xffff) != _ucodesel)
-		printf("cs %x call %d\n", frame.sf_cs, code);
-	if (frame.sf_eip > VM_MAXUSER_ADDRESS) {
-		printf("eip %x call %d\n", frame.sf_eip, code);
-		frame.sf_eip = 0;
+	if (frame.tf_ss != _udatasel)
+		printf("ss %x call %d\n", frame.tf_ss, code);
+	if ((frame.tf_cs&0xffff) != _ucodesel)
+		printf("cs %x call %d\n", frame.tf_cs, code);
+	if (frame.tf_eip > VM_MAXUSER_ADDRESS) {
+		printf("eip %x call %d\n", frame.tf_eip, code);
+		frame.tf_eip = 0;
 	}
 }
 #endif
diff --git a/sys/i386/include/frame.h b/sys/i386/include/frame.h
index c61d17901d30..b36c141e7f83 100644
--- a/sys/i386/include/frame.h
+++ b/sys/i386/include/frame.h
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)frame.h	5.2 (Berkeley) 1/18/91
- *	$Id: frame.h,v 1.5 1993/12/03 05:10:00 alm Exp $
+ *	$Id: frame.h,v 1.6 1993/12/19 00:50:15 wollman Exp $
  */
 
 #ifndef _MACHINE_FRAME_H_
@@ -113,28 +113,5 @@ struct sigframe {
 	int	sf_edx;	
 	int	sf_ecx;	
 	struct	sigcontext sf_sc;
-} ;
-
-/*
- * Call Gate/System Call Stack Frame
- */
-
-struct syscframe {
-	int	sf_edi;
-	int	sf_esi;
-	int	sf_ebp;
-	int	:32;		/* redundant save of isp */
-	int	sf_ebx;
-	int	sf_edx;
-	int	sf_ecx;
-	int	sf_eax;
-	int	sf_eflags;
-	/* below portion defined in 386 hardware */
-/*	int	sf_args[N];*/ 	/* if call gate copy args enabled!*/
-	int	sf_eip;
-	int	sf_cs;
-	/* below only when transitting rings (e.g. user to kernel) */
-	int	sf_esp;
-	int	sf_ss;
 };
 #endif /* _MACHINE_FRAME_H_ */
diff --git a/sys/i386/include/pcb.h b/sys/i386/include/pcb.h
index 1090798ed926..a7a29dfdbb85 100644
--- a/sys/i386/include/pcb.h
+++ b/sys/i386/include/pcb.h
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)pcb.h	5.10 (Berkeley) 5/12/91
- *	$Id: pcb.h,v 1.2 1993/10/08 20:51:00 rgrimes Exp $
+ *	$Id: pcb.h,v 1.3 1993/11/07 17:42:59 wollman Exp $
  */
 
 #ifndef _I386_PCB_H_
@@ -72,7 +72,6 @@ struct pcb {
 #define	FP_NEEDSRESTORE	0x04	/* ... that needs restore on next DNA fault */
 #endif
 #define	FP_USESEMC	0x08	/* process uses EMC memory-mapped mode */
-#define	FM_TRAP		0x10	/* process entered kernel on a trap frame */
 #define	FP_SOFTFP	0x20	/* process using software fltng pnt emulator */
 	short	pcb_iml;	/* interrupt mask level */
 	caddr_t	pcb_onfault;	/* copyin/out fault recovery */
diff --git a/sys/i386/include/reg.h b/sys/i386/include/reg.h
index 969df8782289..4cefae0e1305 100644
--- a/sys/i386/include/reg.h
+++ b/sys/i386/include/reg.h
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)reg.h	5.5 (Berkeley) 1/18/91
- *	$Id: reg.h,v 1.4 1993/11/16 09:54:57 davidg Exp $
+ *	$Id: reg.h,v 1.5 1993/12/03 05:10:08 alm Exp $
  */
 
 #ifndef _MACHINE_REG_H_
@@ -68,28 +68,6 @@
 #define	tESP	(15)
 #define	tSS	(16)
 
-/* During a system call, registers are at these offsets instead of above. */
-
-#define	sEDI	(0)
-#define	sESI	(1)
-#define	sEBP	(2)
-
-#define	sEBX	(4)
-#define	sEDX	(5)
-#define	sECX	(6)
-#define	sEAX	(7)
-#define	sEFLAGS	(8)
-#define	sEIP	(9)
-#define	sCS	(10)
-#define	sESP	(11)
-#define	sSS	(12)
-
-#define PC	sEIP
-#define SP	sESP
-#define PS	sEFLAGS
-#define R0	sEDX
-#define R1	sECX
-
 /*
  * Registers accessible to ptrace(2) syscall for debugger
  * The machine-dependent code for PT_{SET,GET}REGS needs to
diff --git a/sys/i386/isa/npx.c b/sys/i386/isa/npx.c
index 0e90bff2433f..796dfbbae406 100644
--- a/sys/i386/isa/npx.c
+++ b/sys/i386/isa/npx.c
@@ -32,7 +32,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)npx.c	7.2 (Berkeley) 5/12/91
- *	$Id: npx.c,v 1.4 1993/11/03 00:29:19 paul Exp $
+ *	$Id: npx.c,v 1.5 1993/11/03 23:32:35 paul Exp $
  */
 
 #include "npx.h"
@@ -439,7 +439,6 @@ npxintr(frame)
 		 * just before it is used).
 		 */
 		curproc->p_regs = (int *)&frame.if_es;
-		curpcb->pcb_flags |= FM_TRAP;	/* used by sendsig */
 #ifdef notyet
 		/*
 		 * Encode the appropriate code for detailed information on
@@ -450,7 +449,6 @@ npxintr(frame)
 		code = 0;	/* XXX */
 #endif
 		trapsignal(curproc, SIGFPE, code);
-		curpcb->pcb_flags &= ~FM_TRAP;
 	} else {
 		/*
 		 * Nested interrupt.  These losers occur when:
diff --git a/sys/i386/isa/syscons.c b/sys/i386/isa/syscons.c
index b683ea02d0f9..f8c87632aae7 100644
--- a/sys/i386/isa/syscons.c
+++ b/sys/i386/isa/syscons.c
@@ -35,7 +35,7 @@
  *
  *	from: @(#)pccons.c	5.11 (Berkeley) 5/21/91
  *	from: @(#)syscons.c	1.1 931021
- *	$Id: syscons.c,v 1.22 1993/12/21 02:49:13 rich Exp $
+ *	$Id: syscons.c,v 1.23 1993/12/21 03:27:26 rich Exp $
  *
  * Heavily modified by Søren Schmidt (sos@login.dkuug.dk) to provide:
  *
@@ -526,14 +526,8 @@ pcparam(struct tty *tp, struct termios *t)
 	return(0);
 }
 
-
-#if defined(NetBSD)
 #define	frametype	struct trapframe 
 #define eflags		tf_eflags
-#else
-#define	frametype	struct syscframe
-#define eflags		sf_eflags
-#endif
 
 int
 pcioctl(dev_t dev, int cmd, caddr_t data, int flag, struct proc *p)
diff --git a/sys/isa/syscons.c b/sys/isa/syscons.c
index b683ea02d0f9..f8c87632aae7 100644
--- a/sys/isa/syscons.c
+++ b/sys/isa/syscons.c
@@ -35,7 +35,7 @@
  *
  *	from: @(#)pccons.c	5.11 (Berkeley) 5/21/91
  *	from: @(#)syscons.c	1.1 931021
- *	$Id: syscons.c,v 1.22 1993/12/21 02:49:13 rich Exp $
+ *	$Id: syscons.c,v 1.23 1993/12/21 03:27:26 rich Exp $
  *
  * Heavily modified by Søren Schmidt (sos@login.dkuug.dk) to provide:
  *
@@ -526,14 +526,8 @@ pcparam(struct tty *tp, struct termios *t)
 	return(0);
 }
 
-
-#if defined(NetBSD)
 #define	frametype	struct trapframe 
 #define eflags		tf_eflags
-#else
-#define	frametype	struct syscframe
-#define eflags		sf_eflags
-#endif
 
 int
 pcioctl(dev_t dev, int cmd, caddr_t data, int flag, struct proc *p)
diff --git a/sys/kern/subr_trap.c b/sys/kern/subr_trap.c
index 41370cc46631..c85ac5786bd7 100644
--- a/sys/kern/subr_trap.c
+++ b/sys/kern/subr_trap.c
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)trap.c	7.4 (Berkeley) 5/13/91
- *	$Id: trap.c,v 1.11 1993/12/12 12:22:57 davidg Exp $
+ *	$Id: trap.c,v 1.12 1993/12/19 00:50:09 wollman Exp $
  */
 
 /*
@@ -179,7 +179,6 @@ if(curpcb == 0 || curproc == 0) goto we_re_toast;
 	if (ISPL(frame.tf_cs) == SEL_UPL) {
 		type |= T_USER;
 		p->p_regs = (int *)&frame;
-		curpcb->pcb_flags |= FM_TRAP;	/* used by sendsig */
 	}
 
 	ucode=0;
@@ -487,7 +486,6 @@ if(curpcb == 0 || curproc == 0) goto we_re_toast;
 		}
 	}
 	curpri = p->p_pri;
-	curpcb->pcb_flags &= ~FM_TRAP;	/* used by sendsig */
 }
 
 /*
@@ -575,7 +573,7 @@ int trapwrite(addr)
 /*ARGSUSED*/
 void
 syscall(frame)
-	volatile struct syscframe frame;
+	volatile struct trapframe frame;
 {
 	register int *locr0 = ((int *)&frame);
 	register caddr_t params;
@@ -591,29 +589,30 @@ syscall(frame)
 	r0 = 0; r0 = r0; r1 = 0; r1 = r1;
 #endif
 	syst = p->p_stime;
-	if (ISPL(frame.sf_cs) != SEL_UPL)
+	if (ISPL(frame.tf_cs) != SEL_UPL)
 		panic("syscall");
 
-	code = frame.sf_eax;
-	curpcb->pcb_flags &= ~FM_TRAP;	/* used by sendsig */
+	code = frame.tf_eax;
 	p->p_regs = (int *)&frame;
-	params = (caddr_t)frame.sf_esp + sizeof (int) ;
+	params = (caddr_t)frame.tf_esp + sizeof (int) ;
 
 	/*
 	 * Reconstruct pc, assuming lcall $X,y is 7 bytes, as it is always.
 	 */
-	opc = frame.sf_eip - 7;
-	callp = (code >= nsysent) ? &sysent[63] : &sysent[code];
-	if (callp == sysent) {
-		i = fuword(params);
+	opc = frame.tf_eip - 7;
+	if (code == 0) {
+		code = fuword(params);
 		params += sizeof (int);
-		callp = (code >= nsysent) ? &sysent[63] : &sysent[code];
 	}
+	if (code < 0 || code >= nsysent)
+		callp = &sysent[0];
+	else
+		callp = &sysent[code];
 
 	if ((i = callp->sy_narg * sizeof (int)) &&
 	    (error = copyin(params, (caddr_t)args, (u_int)i))) {
-		frame.sf_eax = error;
-		frame.sf_eflags |= PSL_C;	/* carry bit */
+		frame.tf_eax = error;
+		frame.tf_eflags |= PSL_C;	/* carry bit */
 #ifdef KTRACE
 		if (KTRPOINT(p, KTR_SYSCALL))
 			ktrsyscall(p->p_tracep, code, callp->sy_narg, args);
@@ -625,20 +624,20 @@ syscall(frame)
 		ktrsyscall(p->p_tracep, code, callp->sy_narg, args);
 #endif
 	rval[0] = 0;
-	rval[1] = frame.sf_edx;
+	rval[1] = frame.tf_edx;
 /*pg("%d. s %d\n", p->p_pid, code);*/
 	error = (*callp->sy_call)(p, args, rval);
 	if (error == ERESTART)
-		frame.sf_eip = opc;
+		frame.tf_eip = opc;
 	else if (error != EJUSTRETURN) {
 		if (error) {
 /*pg("error %d", error);*/
-			frame.sf_eax = error;
-			frame.sf_eflags |= PSL_C;	/* carry bit */
+			frame.tf_eax = error;
+			frame.tf_eflags |= PSL_C;	/* carry bit */
 		} else {
-			frame.sf_eax = rval[0];
-			frame.sf_edx = rval[1];
-			frame.sf_eflags &= ~PSL_C;	/* carry bit */
+			frame.tf_eax = rval[0];
+			frame.tf_edx = rval[1];
+			frame.tf_eflags &= ~PSL_C;	/* carry bit */
 		}
 	}
 	/* else if (error == EJUSTRETURN) */
@@ -679,10 +678,10 @@ syscall(frame)
 		if (ticks) {
 #ifdef PROFTIMER
 			extern int profscale;
-			addupc(frame.sf_eip, &p->p_stats->p_prof,
+			addupc(frame.tf_eip, &p->p_stats->p_prof,
 			    ticks * profscale);
 #else
-			addupc(frame.sf_eip, &p->p_stats->p_prof, ticks);
+			addupc(frame.tf_eip, &p->p_stats->p_prof, ticks);
 #endif
 		}
 	}
@@ -693,13 +692,13 @@ syscall(frame)
 #endif
 #ifdef	DIAGNOSTICx
 { extern int _udatasel, _ucodesel;
-	if (frame.sf_ss != _udatasel)
-		printf("ss %x call %d\n", frame.sf_ss, code);
-	if ((frame.sf_cs&0xffff) != _ucodesel)
-		printf("cs %x call %d\n", frame.sf_cs, code);
-	if (frame.sf_eip > VM_MAXUSER_ADDRESS) {
-		printf("eip %x call %d\n", frame.sf_eip, code);
-		frame.sf_eip = 0;
+	if (frame.tf_ss != _udatasel)
+		printf("ss %x call %d\n", frame.tf_ss, code);
+	if ((frame.tf_cs&0xffff) != _ucodesel)
+		printf("cs %x call %d\n", frame.tf_cs, code);
+	if (frame.tf_eip > VM_MAXUSER_ADDRESS) {
+		printf("eip %x call %d\n", frame.tf_eip, code);
+		frame.tf_eip = 0;
 	}
 }
 #endif