Merge samba.org:/scratch/anton/export

into samba.org:/scratch/anton/linux-2.5_ppc64

arch/ppc64/Makefile

@@ -18,7 +18,7 @@ KERNELLOAD	:= 0xc000000000000000
 LDFLAGS		:= -m elf64ppc
 LDFLAGS_vmlinux	:= -Bstatic -e $(KERNELLOAD) -Ttext $(KERNELLOAD)
 CFLAGS		+= -msoft-float -pipe -Wno-uninitialized -mminimal-toc \
-		-mtraceback=full -mcpu=power4
+		-mcpu=power4
 
 have_zero_bss := $(shell if $(CC) -fno-zero-initialized-in-bss -S -o /dev/null -xc /dev/null > /dev/null 2>&1; then echo y; else echo n; fi)
 

arch/ppc64/kernel/irq.c

@@ -39,6 +39,7 @@
 #include <linux/irq.h>
 #include <linux/proc_fs.h>
 #include <linux/random.h>
+#include <linux/kallsyms.h>
 
 #include <asm/uaccess.h>
 #include <asm/bitops.h>
@@ -350,14 +351,11 @@ int show_interrupts(struct seq_file *p, void *v)
 	return 0;
 }
 
-extern char *ppc_find_proc_name(unsigned *p, char *buf, unsigned buflen);
-
-static inline void handle_irq_event(int irq, struct pt_regs *regs,
+static inline int handle_irq_event(int irq, struct pt_regs *regs,
 				   struct irqaction *action)
 {
 	int status = 0;
 	int retval = 0;
-	struct irqaction *first_action = action;
 
 	if (!(action->flags & SA_INTERRUPT))
 		local_irq_enable();
@@ -370,28 +368,88 @@ static inline void handle_irq_event(int irq, struct pt_regs *regs,
 	if (status & SA_SAMPLE_RANDOM)
 		add_interrupt_randomness(irq);
 	local_irq_disable();
-	if (retval != 1) {
-		static int count = 100;
-		char name_buf[256];
-		if (count) {
-			count--;
-			if (retval) {
-				printk("irq event %d: bogus retval mask %x\n",
-					irq, retval);
+	return retval;
+}
+
+static void __report_bad_irq(int irq, irq_desc_t *desc, irqreturn_t action_ret)
+{
+	struct irqaction *action;
+
+	if (action_ret != IRQ_HANDLED && action_ret != IRQ_NONE) {
+		printk(KERN_ERR "irq event %d: bogus return value %x\n",
+				irq, action_ret);
 	} else {
-				printk("irq %d: nobody cared!\n", irq);
+		printk(KERN_ERR "irq %d: nobody cared!\n", irq);
 	}
 	dump_stack();
-			printk("handlers:\n");
-			action = first_action;
+	printk(KERN_ERR "handlers:\n");
+	action = desc->action;
 	do {
-				printk("[<%p>]", action->handler);
-				printk(" (%s)\n",
-				       ppc_find_proc_name((unsigned *)action->handler, name_buf, 256));
+		printk(KERN_ERR "[<%p>]", action->handler);
+		print_symbol(" (%s)",
+			(unsigned long)action->handler);
+		printk("\n");
 		action = action->next;
 	} while (action);
+}
+
+static void report_bad_irq(int irq, irq_desc_t *desc, irqreturn_t action_ret)
+{
+	static int count = 100;
+
+	if (count) {
+		count--;
+		__report_bad_irq(irq, desc, action_ret);
+	}
+}
+
+static int noirqdebug;
+
+static int __init noirqdebug_setup(char *str)
+{
+	noirqdebug = 1;
+	printk("IRQ lockup detection disabled\n");
+	return 1;
+}
+
+__setup("noirqdebug", noirqdebug_setup);
+
+/*
+ * If 99,900 of the previous 100,000 interrupts have not been handled then
+ * assume that the IRQ is stuck in some manner.  Drop a diagnostic and try to
+ * turn the IRQ off.
+ *
+ * (The other 100-of-100,000 interrupts may have been a correctly-functioning
+ *  device sharing an IRQ with the failing one)
+ *
+ * Called under desc->lock
+ */
+static void note_interrupt(int irq, irq_desc_t *desc, irqreturn_t action_ret)
+{
+	if (action_ret != IRQ_HANDLED) {
+		desc->irqs_unhandled++;
+		if (action_ret != IRQ_NONE)
+			report_bad_irq(irq, desc, action_ret);
 	}
+
+	desc->irq_count++;
+	if (desc->irq_count < 100000)
+		return;
+
+	desc->irq_count = 0;
+	if (desc->irqs_unhandled > 99900) {
+		/*
+		 * The interrupt is stuck
+		 */
+		__report_bad_irq(irq, desc, action_ret);
+		/*
+		 * Now kill the IRQ
+		 */
+		printk(KERN_EMERG "Disabling IRQ #%d\n", irq);
+		desc->status |= IRQ_DISABLED;
+		desc->handler->disable(irq);
 	}
+	desc->irqs_unhandled = 0;
 }
 
 /*
@@ -462,10 +520,13 @@ void ppc_irq_dispatch_handler(struct pt_regs *regs, int irq)
 	 * SMP environment.
 	 */
 	for (;;) {
+		irqreturn_t action_ret;
+
 		spin_unlock(&desc->lock);
-		handle_irq_event(irq, regs, action);
+		action_ret = handle_irq_event(irq, regs, action);
 		spin_lock(&desc->lock);
-		
+		if (!noirqdebug)
+			note_interrupt(irq, desc, action_ret);
 		if (likely(!(desc->status & IRQ_PENDING)))
 			break;
 		desc->status &= ~IRQ_PENDING;

arch/ppc64/kernel/process.c

@@ -32,6 +32,7 @@
 #include <linux/init_task.h>
 #include <linux/prctl.h>
 #include <linux/ptrace.h>
+#include <linux/kallsyms.h>
 
 #include <asm/pgtable.h>
 #include <asm/uaccess.h>
@@ -130,12 +131,9 @@ struct task_struct *__switch_to(struct task_struct *prev,
 	return last;
 }
 
-char *ppc_find_proc_name(unsigned *p, char *buf, unsigned buflen);
-
 void show_regs(struct pt_regs * regs)
 {
 	int i;
-	char name_buf[256];
 
 	printk("NIP: %016lX XER: %016lX LR: %016lX\n",
 	       regs->nip, regs->xer, regs->link);
@@ -170,8 +168,7 @@ void show_regs(struct pt_regs * regs)
 	 * above info out without failing
 	 */
 	printk("NIP [%016lx] ", regs->nip);
-	printk("%s\n", ppc_find_proc_name((unsigned *)regs->nip,
-	       name_buf, 256));
+	print_symbol("%s\n", regs->nip);
 	show_stack(current, (unsigned long *)regs->gpr[1]);
 }
 
@@ -385,62 +382,6 @@ int sys_execve(unsigned long a0, unsigned long a1, unsigned long a2,
 	return error;
 }
 
-char *ppc_find_proc_name(unsigned *p, char *buf, unsigned buflen)
-{
-	unsigned long tb_flags;
-	unsigned short name_len;
-	unsigned long tb_start, code_start, code_ptr, code_offset;
-	unsigned int code_len;
-	unsigned long end;
-
-	strcpy(buf, "Unknown");
-	code_ptr = (unsigned long)p;
-	code_offset = 0;
-
-	/* handle functions in text and init sections */
-	if (((unsigned long)p >= (unsigned long)_stext) && 
-	    ((unsigned long)p < (unsigned long)_etext))
-		end = (unsigned long)_etext;
-	else if (((unsigned long)p >= (unsigned long)__init_begin) && 
-		 ((unsigned long)p < (unsigned long)__init_end))
-		end = (unsigned long)__init_end;
-	else
-		return buf;
-
-	while ((unsigned long)p < end) {
-		if (*p == 0) {
-			tb_start = (unsigned long)p;
-			++p;	/* Point to traceback flags */
-			tb_flags = *((unsigned long *)p);
-			p += 2;	/* Skip over traceback flags */
-			if (tb_flags & TB_NAME_PRESENT) {
-				if (tb_flags & TB_PARMINFO)
-					++p;	/* skip over parminfo data */
-				if (tb_flags & TB_HAS_TBOFF) {
-					code_len = *p;	/* get code length */
-					code_start = tb_start - code_len;
-					code_offset = code_ptr - code_start + 1;
-					if (code_offset > 0x100000)
-						break;
-					++p;	/* skip over code size */
-				}
-				name_len = *((unsigned short *)p);
-				if (name_len > (buflen-20))
-					name_len = buflen-20;
-				memcpy(buf, ((char *)p)+2, name_len);
-				buf[name_len] = 0;
-				if (code_offset)
-					sprintf(buf+name_len, "+0x%lx",
-						code_offset-1); 
-			}
-			break;
-		}
-		++p;
-	}
-
-	return buf;
-}
-
 /*
  * These bracket the sleeping functions..
  */
@@ -480,7 +421,6 @@ void show_stack(struct task_struct *p, unsigned long *_sp)
 	unsigned long ip;
 	unsigned long stack_page = (unsigned long)p->thread_info;
 	int count = 0;
-	char name_buf[256];
 	unsigned long sp = (unsigned long)_sp;
 
 	if (!p)
@@ -499,8 +439,7 @@ void show_stack(struct task_struct *p, unsigned long *_sp)
 		if (__get_user(ip, (unsigned long *)(sp + 16)))
 			break;
 		printk("[%016lx] ", ip);
-		printk("%s\n", ppc_find_proc_name((unsigned *)ip,
-		       name_buf, 256));
+		print_symbol("%s\n", ip);
 	} while (count++ < 32);
 }
 

arch/ppc64/xmon/xmon.c

@@ -15,6 +15,8 @@
 #include <linux/mm.h>
 #include <linux/reboot.h>
 #include <linux/delay.h>
+#include <linux/kallsyms.h>
+
 #include <asm/ptrace.h>
 #include <asm/string.h>
 #include <asm/prom.h>
@@ -27,6 +29,7 @@
 #include <asm/paca.h>
 #include <asm/ppcdebug.h>
 #include <asm/cputable.h>
+
 #include "nonstdio.h"
 #include "privinst.h"
 
@@ -59,7 +62,6 @@ struct bpt {
 	unsigned instr;
 	unsigned long count;
 	unsigned char enabled;
-	char funcname[64];	/* function name for humans */
 };
 
 #define NBPTS	16
@@ -79,10 +81,6 @@ static void memex(void);
 static int bsesc(void);
 static void dump(void);
 static void prdump(unsigned long, long);
-#ifdef __MWERKS__
-static void prndump(unsigned, int);
-static int nvreadb(unsigned);
-#endif
 static int ppc_inst_dump(unsigned long, long);
 void print_address(unsigned long);
 static int getsp(void);
@@ -105,7 +103,6 @@ static void take_input(char *);
 static unsigned long read_spr(int);
 static void write_spr(int, unsigned long);
 static void super_regs(void);
-static void print_sysmap(void);
 static void remove_bpts(void);
 static void insert_bpts(void);
 static struct bpt *at_breakpoint(unsigned long pc);
@@ -181,6 +178,13 @@ static int xmon_trace[NR_CPUS];
 
 static struct pt_regs *xmon_regs[NR_CPUS];
 
+void __xmon_print_symbol(const char *fmt, unsigned long address);
+#define xmon_print_symbol(fmt, addr)		\
+do {						\
+	__check_printsym_format(fmt, "");	\
+	__xmon_print_symbol(fmt, addr);		\
+} while(0)
+
 /*
  * Stuff for reading and writing memory safely
  */
@@ -209,42 +213,6 @@ extern inline void sync(void)
  no functions have been called from the current function.
  */
 
-/*
- A traceback table typically follows each function.
- The find_tb_table() func will fill in this struct.  Note that the struct
- is not an exact match with the encoded table defined by the ABI.  It is
- defined here more for programming convenience.
- */
-struct tbtable {
-	unsigned long	flags;		/* flags: */
-#define TBTAB_FLAGSGLOBALLINK	(1L<<47)
-#define TBTAB_FLAGSISEPROL	(1L<<46)
-#define TBTAB_FLAGSHASTBOFF	(1L<<45)
-#define TBTAB_FLAGSINTPROC	(1L<<44)
-#define TBTAB_FLAGSHASCTL	(1L<<43)
-#define TBTAB_FLAGSTOCLESS	(1L<<42)
-#define TBTAB_FLAGSFPPRESENT	(1L<<41)
-#define TBTAB_FLAGSNAMEPRESENT	(1L<<38)
-#define TBTAB_FLAGSUSESALLOCA	(1L<<37)
-#define TBTAB_FLAGSSAVESCR	(1L<<33)
-#define TBTAB_FLAGSSAVESLR	(1L<<32)
-#define TBTAB_FLAGSSTORESBC	(1L<<31)
-#define TBTAB_FLAGSFIXUP	(1L<<30)
-#define TBTAB_FLAGSPARMSONSTK	(1L<<0)
-	unsigned char	fp_saved;	/* num fp regs saved f(32-n)..f31 */
-	unsigned char	gpr_saved;	/* num gpr's saved */
-	unsigned char	fixedparms;	/* num fixed point parms */
-	unsigned char	floatparms;	/* num float parms */
-	unsigned char	parminfo[32];	/* types of args.  null terminated */
-#define TBTAB_PARMFIXED 1
-#define TBTAB_PARMSFLOAT 2
-#define TBTAB_PARMDFLOAT 3
-	unsigned int	tb_offset;	/* offset from start of func */
-	unsigned long	funcstart;	/* addr of start of function */
-	char		name[64];	/* name of function (null terminated)*/
-};
-static int find_tb_table(unsigned long codeaddr, struct tbtable *tab);
-
 #define SURVEILLANCE_TOKEN	9000
 
 static inline void disable_surveillance(void)
@@ -302,8 +270,7 @@ xmon(struct pt_regs *excp)
 			std	29,232(%0)\n\
 			std	30,240(%0)\n\
 			std	31,248(%0)" : : "b" (&regs));
-		/* Fetch the link reg for this stack frame.
-		 NOTE: the prev printf fills in the lr. */
+
 		regs.nip = regs.link = ((unsigned long *)(regs.gpr[1]))[2];
 		regs.msr = get_msr();
 		regs.ctr = get_ctr();
@@ -378,7 +345,9 @@ xmon_bpt(struct pt_regs *regs)
 		xmon_trace[smp_processor_id()] = BRSTEP;
 		regs->msr |= MSR_SE;
 	} else {
-		printf("Stopped at breakpoint %x (%lx %s)\n", (bp - bpts)+1, bp->address, bp->funcname);
+		printf("Stopped at breakpoint %x (%lx ", (bp - bpts) + 1,
+			bp->address);
+		xmon_print_symbol("%s)\n", bp->address);
 		xmon(regs);
 	}
 	return 1;
@@ -576,9 +545,6 @@ cmds(struct pt_regs *excp)
 			else
 				excprint(excp);
 			break;
-		case 'M':
-			print_sysmap();
-			break;
 		case 'S':
 			super_regs();
 			break;
@@ -768,7 +734,6 @@ bpt_cmds(void)
 	unsigned long a;
 	int mode, i;
 	struct bpt *bp;
-	struct tbtable tab;
 
 	cmd = inchar();
 	switch (cmd) {
@@ -824,7 +789,9 @@ bpt_cmds(void)
 			if (bp == 0) {
 				printf("No breakpoint at %x\n", a);
 			} else {
-				printf("Cleared breakpoint %x (%lx %s)\n", (bp - bpts)+1, bp->address, bp->funcname);
+				printf("Cleared breakpoint %x (%lx ", 
+					(bp - bpts) + 1, bp->address);
+				xmon_print_symbol("%s)\n", bp->address);
 				bp->enabled = 0;
 			}
 		}
@@ -858,8 +825,11 @@ bpt_cmds(void)
 				printf("   inst   %.16lx %8x\n", iabr.address & ~3,
 				       iabr.count);
 			for (bp = bpts, bpnum = 1; bp < &bpts[NBPTS]; ++bp, ++bpnum)
-				if (bp->enabled)
-					printf("%2x trap   %.16lx %8x  %s\n", bpnum, bp->address, bp->count, bp->funcname);
+				if (bp->enabled) {
+					printf("%2x trap   %.16lx %8x  ",
+						bpnum, bp->address, bp->count);
+					xmon_print_symbol("%s\n", bp->address);
+				}
 			break;
 		}
 		bp = at_breakpoint(a);
@@ -876,14 +846,9 @@ bpt_cmds(void)
 		bp->address = a;
 		bp->count = 0;
 		scanhex(&bp->count);
-		/* Find the function name just once. */
-		bp->funcname[0] = '\0';
-		if (find_tb_table(bp->address, &tab) && tab.name[0]) {
-			/* Got a nice name for it. */
-			int delta = bp->address - tab.funcstart;
-			sprintf(bp->funcname, "%s+0x%x", tab.name, delta);
-		}
-		printf("Set breakpoint %2x trap   %.16lx %8x  %s\n", (bp-bpts)+1, bp->address, bp->count, bp->funcname);
+		printf("Set breakpoint %2x trap   %.16lx %8x  ", (bp-bpts) + 1, 
+			bp->address, bp->count);
+		xmon_print_symbol("%s\n", bp->address);
 		break;
 	}
 }
@@ -920,7 +885,6 @@ backtrace(struct pt_regs *excp)
 	unsigned long lr;
 	unsigned long stack[3];
 	struct pt_regs regs;
-	struct tbtable tab;
 	int framecount;
 	char *funcname;
 	/* declare these as raw ptrs so we don't get func descriptors */
@@ -966,14 +930,8 @@ backtrace(struct pt_regs *excp)
 				break;
 			printf("exception: %lx %s regs %lx\n", regs.trap, getvecname(regs.trap), sp+112);
 			printf("                  %.16lx", regs.nip);
-			if ((regs.nip & 0xffffffff00000000UL) &&
-			    find_tb_table(regs.nip, &tab)) {
-				int delta = regs.nip-tab.funcstart;
-				if (delta < 0)
-					printf("  <unknown code>");
-				else
-					printf("  %s+0x%x", tab.name, delta);
-			}
+			if (regs.nip & 0xffffffff00000000UL)
+				xmon_print_symbol("  %s", regs.nip);
 			printf("\n");
                         if (regs.gpr[1] < sp) {
                             printf("<Stack drops into userspace %.16lx>\n", regs.gpr[1]);
@@ -984,13 +942,8 @@ backtrace(struct pt_regs *excp)
 			if (mread(sp, stack, sizeof(stack)) != sizeof(stack))
 				break;
 		} else {
-			if (stack[2] && find_tb_table(stack[2], &tab)) {
-				int delta = stack[2]-tab.funcstart;
-				if (delta < 0)
-					printf("  <unknown code>");
-				else
-					printf("  %s+0x%x", tab.name, delta);
-			}
+			if (stack[2])
+				xmon_print_symbol("  %s", stack[2]);
 			printf("\n");
 		}
 		if (stack[0] && stack[0] <= sp) {
@@ -1019,8 +972,6 @@ spinlock_t exception_print_lock = SPIN_LOCK_UNLOCKED;
 void
 excprint(struct pt_regs *fp)
 {
-	struct task_struct *c;
-	struct tbtable tab;
 	unsigned long flags;
 
 	spin_lock_irqsave(&exception_print_lock, flags);
@@ -1031,19 +982,11 @@ excprint(struct pt_regs *fp)
 
 	printf("Vector: %lx %s at [%lx]\n", fp->trap, getvecname(fp->trap), fp);
 	printf("    pc: %lx", fp->nip);
-	if (find_tb_table(fp->nip, &tab) && tab.name[0]) {
-		/* Got a nice name for it */
-		int delta = fp->nip - tab.funcstart;
-		printf(" (%s+0x%x)", tab.name, delta);
-	}
-	printf("\n");
+	xmon_print_symbol(" (%s)\n", fp->nip);
+
 	printf("    lr: %lx", fp->link);
-	if (find_tb_table(fp->link, &tab) && tab.name[0]) {
-		/* Got a nice name for it */
-		int delta = fp->link - tab.funcstart;
-		printf(" (%s+0x%x)", tab.name, delta);
-	}
-	printf("\n");
+	xmon_print_symbol(" (%s)\n", fp->link);
+
 	printf("    sp: %lx\n", fp->gpr[1]);
 	printf("   msr: %lx\n", fp->msr);
 
@@ -1052,13 +995,11 @@ excprint(struct pt_regs *fp)
 		printf(" dsisr: %lx\n", fp->dsisr);
 	}
 
-	/* XXX: need to copy current or we die.  Why? */
-	c = current;
-	printf("  current = 0x%lx\n", c);
+	printf("  current = 0x%lx\n", current);
 	printf("  paca    = 0x%lx\n", get_paca());
-	if (c) {
-		printf("  current = %lx, pid = %ld, comm = %s\n",
-		       c, c->pid, c->comm);
+	if (current) {
+		printf("    pid   = %ld, comm = %s\n",
+		       current->pid, current->comm);
 	}
 
 	spin_unlock_irqrestore(&exception_print_lock, flags);
@@ -1147,14 +1088,6 @@ static unsigned long regno;
 extern char exc_prolog;
 extern char dec_exc;
 
-void
-print_sysmap(void)
-{
-	extern char *sysmap;
-	if ( sysmap )
-		printf("System.map: \n%s", sysmap);
-}
-
 void
 super_regs()
 {
@@ -1922,111 +1855,52 @@ char *str;
 	lineptr = str;
 }
 
-
-/* Starting at codeaddr scan forward for a tbtable and fill in the
- given table.  Return non-zero if successful at doing something.
- */
-static int
-find_tb_table(unsigned long codeaddr, struct tbtable *tab)
+/* xmon version of __print_symbol */
+void __xmon_print_symbol(const char *fmt, unsigned long address)
 {
-	unsigned long codeaddr_max;
-	unsigned long tbtab_start;
-	int nr;
-	int instr;
-	int num_parms;
-
-	/* don't look for traceback table in userspace */
-	if (codeaddr < PAGE_OFFSET)
-		return 0;
+	char *modname;
+	const char *name;
+	unsigned long offset, size;
+	char namebuf[128];
 
-	if (tab == NULL)
-		return 0;
-	memset(tab, 0, sizeof(tab));
-
-	/* Scan instructions starting at codeaddr for 128k max */
-	for (codeaddr_max = codeaddr + 128*1024*4;
-	     codeaddr < codeaddr_max;
-	     codeaddr += 4) {
-		nr = mread(codeaddr, &instr, 4);
-		if (nr != 4)
-			return 0;	/* Bad read.  Give up promptly. */
-		if (instr == 0) {
-			/* table should follow. */
-			int version;
-			unsigned long flags;
-			tbtab_start = codeaddr;	/* save it to compute func start addr */
-			codeaddr += 4;
-			nr = mread(codeaddr, &flags, 8);
-			if (nr != 8)
-				return 0;	/* Bad read or no tb table. */
-			tab->flags = flags;
-			version = (flags >> 56) & 0xff;
-			if (version != 0)
-				continue;	/* No tb table here. */
-			/* Now, like the version, some of the flags are values
-			 that are more conveniently extracted... */
-			tab->fp_saved = (flags >> 24) & 0x3f;
-			tab->gpr_saved = (flags >> 16) & 0x3f;
-			tab->fixedparms = (flags >> 8) & 0xff;
-			tab->floatparms = (flags >> 1) & 0x7f;
-			codeaddr += 8;
-			num_parms = tab->fixedparms + tab->floatparms;
-			if (num_parms) {
-				unsigned int parminfo;
-				int parm;
-				if (num_parms > 32)
-					return 1;	/* incomplete */
-				nr = mread(codeaddr, &parminfo, 4);
-				if (nr != 4)
-					return 1;	/* incomplete */
-				/* decode parminfo...32 bits.
-				 A zero means fixed.  A one means float and the
-				 following bit determines single (0) or double (1).
-				 */
-				for (parm = 0; parm < num_parms; parm++) {
-					if (parminfo & 0x80000000) {
-						parminfo <<= 1;
-						if (parminfo & 0x80000000)
-							tab->parminfo[parm] = TBTAB_PARMDFLOAT;
-						else
-							tab->parminfo[parm] = TBTAB_PARMSFLOAT;
+	if (setjmp(bus_error_jmp) == 0) {
+		debugger_fault_handler = handle_fault;
+		sync();
+		name = kallsyms_lookup(address, &size, &offset, &modname,
+				       namebuf);
+		sync();
+		/* wait a little while to see if we get a machine check */
+		__delay(200);
 	} else {
-						tab->parminfo[parm] = TBTAB_PARMFIXED;
-					}
-					parminfo <<= 1;
-				}
-				codeaddr += 4;
-			}
-			if (flags & TBTAB_FLAGSHASTBOFF) {
-				nr = mread(codeaddr, &tab->tb_offset, 4);
-				if (nr != 4)
-					return 1;	/* incomplete */
-				if (tab->tb_offset > 0) {
-					tab->funcstart = tbtab_start - tab->tb_offset;
-				}
-				codeaddr += 4;
-			}
-			/* hand_mask appears to be always be omitted. */
-			if (flags & TBTAB_FLAGSHASCTL) {
-				/* Assume this will never happen for C or asm */
-				return 1;	/* incomplete */
-			}
-			if (flags & TBTAB_FLAGSNAMEPRESENT) {
-				short namlen;
-				nr = mread(codeaddr, &namlen, 2);
-				if (nr != 2)
-					return 1;	/* incomplete */
-				if (namlen >= sizeof(tab->name))
-					namlen = sizeof(tab->name)-1;
-				codeaddr += 2;
-				nr = mread(codeaddr, tab->name, namlen);
-				tab->name[namlen] = '\0';
-				codeaddr += namlen;
+		name = "symbol lookup failed";
 	}
-			return 1;
+
+	debugger_fault_handler = 0;
+
+	if (!name) {
+		char addrstr[sizeof("0x%lx") + (BITS_PER_LONG*3/10)];
+
+		sprintf(addrstr, "0x%lx", address);
+		printf(fmt, addrstr);
+		return;
 	}
+
+	if (modname) {
+		/* This is pretty small. */
+		char buffer[sizeof("%s+%#lx/%#lx [%s]")
+			   + strlen(name) + 2*(BITS_PER_LONG*3/10)
+			   + strlen(modname)];
+
+		sprintf(buffer, "%s+%#lx/%#lx [%s]",
+			name, offset, size, modname);
+		printf(fmt, buffer);
+	} else {
+		char buffer[sizeof("%s+%#lx/%#lx")
+			   + strlen(name) + 2*(BITS_PER_LONG*3/10)];
+
+		sprintf(buffer, "%s+%#lx/%#lx", name, offset, size);
+		printf(fmt, buffer);
 	}
-	return 0;	/* hit max...sorry. */
 }
 
 void