15 files changed, 195 insertions, 159 deletions

diff --git a/arch/mips/kernel/Makefile b/arch/mips/kernel/Makefile
index 881c467c698..cd9cec9e39e 100644
--- a/arch/mips/kernel/Makefile
+++ b/arch/mips/kernel/Makefile
@@ -11,6 +11,7 @@ obj-y		+= cpu-probe.o branch.o entry.o genex.o irq.o process.o \
 binfmt_irix-objs	:= irixelf.o irixinv.o irixioctl.o irixsig.o	\
 			   irix5sys.o sysirix.o
 
+obj-$(CONFIG_STACKTRACE)	+= stacktrace.o
 obj-$(CONFIG_MODULES)		+= mips_ksyms.o module.o
 
 obj-$(CONFIG_APM)		+= apm.o
diff --git a/arch/mips/kernel/genex.S b/arch/mips/kernel/genex.S
index 37fda3dcdfc..af6ef2fd830 100644
--- a/arch/mips/kernel/genex.S
+++ b/arch/mips/kernel/genex.S
@@ -220,8 +220,8 @@ NESTED(except_vec_vi_handler, 0, sp)
 	CLI
 	TRACE_IRQS_OFF
 	move	a0, sp
-	jalr	v0
-	j	ret_from_irq
+	PTR_LA	ra, ret_from_irq
+	jr	v0
 	END(except_vec_vi_handler)
 
 /*
@@ -349,8 +349,8 @@ NESTED(nmi_handler, PT_SIZE, sp)
 	.set	at
 	__BUILD_\verbose \exception
 	move	a0, sp
-	jal	do_\handler
-	j	ret_from_exception
+	PTR_LA	ra, ret_from_exception
+	j	do_\handler
 	END(handle_\exception)
 	.endm
 
diff --git a/arch/mips/kernel/i8259.c b/arch/mips/kernel/i8259.c
index ea36c8e8852..48e3418c217 100644
--- a/arch/mips/kernel/i8259.c
+++ b/arch/mips/kernel/i8259.c
@@ -302,11 +302,11 @@ static struct irqaction irq2 = {
 };
 
 static struct resource pic1_io_resource = {
-	.name = "pic1", .start = 0x20, .end = 0x3f, .flags = IORESOURCE_BUSY
+	.name = "pic1", .start = 0x20, .end = 0x21, .flags = IORESOURCE_BUSY
 };
 
 static struct resource pic2_io_resource = {
-	.name = "pic2", .start = 0xa0, .end = 0xbf, .flags = IORESOURCE_BUSY
+	.name = "pic2", .start = 0xa0, .end = 0xa1, .flags = IORESOURCE_BUSY
 };
 
 /*
diff --git a/arch/mips/kernel/linux32.c b/arch/mips/kernel/linux32.c
index 43b1162d714..53f4171fc18 100644
--- a/arch/mips/kernel/linux32.c
+++ b/arch/mips/kernel/linux32.c
@@ -77,6 +77,8 @@ int cp_compat_stat(struct kstat *stat, struct compat_stat __user *statbuf)
 	memset(&tmp, 0, sizeof(tmp));
 	tmp.st_dev = new_encode_dev(stat->dev);
 	tmp.st_ino = stat->ino;
+	if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
+		return -EOVERFLOW;
 	tmp.st_mode = stat->mode;
 	tmp.st_nlink = stat->nlink;
 	SET_UID(tmp.st_uid, stat->uid);
@@ -1039,7 +1041,7 @@ asmlinkage long sys32_newuname(struct new_utsname __user * name)
 	int ret = 0;
 
 	down_read(&uts_sem);
-	if (copy_to_user(name,&system_utsname,sizeof *name))
+	if (copy_to_user(name, utsname(), sizeof *name))
 		ret = -EFAULT;
 	up_read(&uts_sem);
 
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
index 2613a0dd4b8..045d987bc68 100644
--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -40,6 +40,7 @@
 #include <asm/elf.h>
 #include <asm/isadep.h>
 #include <asm/inst.h>
+#include <asm/stacktrace.h>
 #ifdef CONFIG_MIPS_MT_SMTC
 #include <asm/mipsmtregs.h>
 extern void smtc_idle_loop_hook(void);
@@ -398,7 +399,7 @@ unsigned long thread_saved_pc(struct task_struct *tsk)
 #ifdef CONFIG_KALLSYMS
 /* used by show_backtrace() */
 unsigned long unwind_stack(struct task_struct *task, unsigned long *sp,
-			   unsigned long pc, unsigned long ra)
+			   unsigned long pc, unsigned long *ra)
 {
 	unsigned long stack_page;
 	struct mips_frame_info info;
@@ -406,18 +407,42 @@ unsigned long unwind_stack(struct task_struct *task, unsigned long *sp,
 	char namebuf[KSYM_NAME_LEN + 1];
 	unsigned long size, ofs;
 	int leaf;
+	extern void ret_from_irq(void);
+	extern void ret_from_exception(void);
 
 	stack_page = (unsigned long)task_stack_page(task);
 	if (!stack_page)
 		return 0;
 
+	/*
+	 * If we reached the bottom of interrupt context,
+	 * return saved pc in pt_regs.
+	 */
+	if (pc == (unsigned long)ret_from_irq ||
+	    pc == (unsigned long)ret_from_exception) {
+		struct pt_regs *regs;
+		if (*sp >= stack_page &&
+		    *sp + sizeof(*regs) <= stack_page + THREAD_SIZE - 32) {
+			regs = (struct pt_regs *)*sp;
+			pc = regs->cp0_epc;
+			if (__kernel_text_address(pc)) {
+				*sp = regs->regs[29];
+				*ra = regs->regs[31];
+				return pc;
+			}
+		}
+		return 0;
+	}
 	if (!kallsyms_lookup(pc, &size, &ofs, &modname, namebuf))
 		return 0;
 	/*
 	 * Return ra if an exception occured at the first instruction
 	 */
-	if (unlikely(ofs == 0))
-		return ra;
+	if (unlikely(ofs == 0)) {
+		pc = *ra;
+		*ra = 0;
+		return pc;
+	}
 
 	info.func = (void *)(pc - ofs);
 	info.func_size = ofs;	/* analyze from start to ofs */
@@ -436,11 +461,12 @@ unsigned long unwind_stack(struct task_struct *task, unsigned long *sp,
 		 * one. In that cases avoid to return always the
 		 * same value.
 		 */
-		pc = pc != ra ? ra : 0;
+		pc = pc != *ra ? *ra : 0;
 	else
 		pc = ((unsigned long *)(*sp))[info.pc_offset];
 
 	*sp += info.frame_size;
+	*ra = 0;
 	return __kernel_text_address(pc) ? pc : 0;
 }
 #endif
@@ -453,6 +479,7 @@ unsigned long get_wchan(struct task_struct *task)
 	unsigned long pc = 0;
 #ifdef CONFIG_KALLSYMS
 	unsigned long sp;
+	unsigned long ra = 0;
 #endif
 
 	if (!task || task == current || task->state == TASK_RUNNING)
@@ -466,7 +493,7 @@ unsigned long get_wchan(struct task_struct *task)
 	sp = task->thread.reg29 + schedule_mfi.frame_size;
 
 	while (in_sched_functions(pc))
-		pc = unwind_stack(task, &sp, pc, 0);
+		pc = unwind_stack(task, &sp, pc, &ra);
 #endif
 
 out:
diff --git a/arch/mips/kernel/scall32-o32.S b/arch/mips/kernel/scall32-o32.S
index e7178510220..61362e6fa9e 100644
--- a/arch/mips/kernel/scall32-o32.S
+++ b/arch/mips/kernel/scall32-o32.S
@@ -28,18 +28,7 @@
 NESTED(handle_sys, PT_SIZE, sp)
 	.set	noat
 	SAVE_SOME
-#ifdef CONFIG_TRACE_IRQFLAGS
-	TRACE_IRQS_ON
-#ifdef CONFIG_64BIT
-	LONG_L	$8, PT_R8(sp)
-	LONG_L	$9, PT_R9(sp)
-#endif
-	LONG_L	$7, PT_R7(sp)
-	LONG_L	$6, PT_R6(sp)
-	LONG_L	$5, PT_R5(sp)
-	LONG_L	$4, PT_R4(sp)
-	LONG_L	$2, PT_R2(sp)
-#endif
+	TRACE_IRQS_ON_RELOAD
 	STI
 	.set	at
 
diff --git a/arch/mips/kernel/scall64-64.S b/arch/mips/kernel/scall64-64.S
index 4c22d0b4825..6c7b5ed0ea6 100644
--- a/arch/mips/kernel/scall64-64.S
+++ b/arch/mips/kernel/scall64-64.S
@@ -34,7 +34,7 @@ NESTED(handle_sys64, PT_SIZE, sp)
 	 */
 	.set	noat
 	SAVE_SOME
-	TRACE_IRQS_ON
+	TRACE_IRQS_ON_RELOAD
 	STI
 	.set	at
 #endif
diff --git a/arch/mips/kernel/scall64-n32.S b/arch/mips/kernel/scall64-n32.S
index f25c2a2f103..6d9f18727ac 100644
--- a/arch/mips/kernel/scall64-n32.S
+++ b/arch/mips/kernel/scall64-n32.S
@@ -33,7 +33,7 @@ NESTED(handle_sysn32, PT_SIZE, sp)
 #ifndef CONFIG_MIPS32_O32
 	.set	noat
 	SAVE_SOME
-	TRACE_IRQS_ON
+	TRACE_IRQS_ON_RELOAD
 	STI
 	.set	at
 #endif
diff --git a/arch/mips/kernel/scall64-o32.S b/arch/mips/kernel/scall64-o32.S
index 288ee4ac4db..2e6d0673163 100644
--- a/arch/mips/kernel/scall64-o32.S
+++ b/arch/mips/kernel/scall64-o32.S
@@ -28,7 +28,7 @@
 NESTED(handle_sys, PT_SIZE, sp)
 	.set	noat
 	SAVE_SOME
-	TRACE_IRQS_ON
+	TRACE_IRQS_ON_RELOAD
 	STI
 	.set	at
 	ld	t1, PT_EPC(sp)		# skip syscall on return
diff --git a/arch/mips/kernel/signal_n32.c b/arch/mips/kernel/signal_n32.c
index 50c17eaa7f2..477c5334ec1 100644
--- a/arch/mips/kernel/signal_n32.c
+++ b/arch/mips/kernel/signal_n32.c
@@ -42,8 +42,6 @@
 
 #include "signal-common.h"
 
-extern void sigset_from_compat(sigset_t *set, compat_sigset_t *compat);
-
 /*
  * Including <asm/unistd.h> would give use the 64-bit syscall numbers ...
  */
@@ -83,6 +81,8 @@ struct rt_sigframe_n32 {
 #endif
 };
 
+extern void sigset_from_compat (sigset_t *set, compat_sigset_t *compat);
+
 save_static_function(sysn32_rt_sigsuspend);
 __attribute_used__ noinline static int
 _sysn32_rt_sigsuspend(nabi_no_regargs struct pt_regs regs)
diff --git a/arch/mips/kernel/stacktrace.c b/arch/mips/kernel/stacktrace.c
new file mode 100644
index 00000000000..4aabe526a68
--- /dev/null
+++ b/arch/mips/kernel/stacktrace.c
@@ -0,0 +1,85 @@
+/*
+ * arch/mips/kernel/stacktrace.c
+ *
+ * Stack trace management functions
+ *
+ *  Copyright (C) 2006 Atsushi Nemoto <anemo@mba.ocn.ne.jp>
+ */
+#include <linux/sched.h>
+#include <linux/stacktrace.h>
+#include <asm/stacktrace.h>
+
+/*
+ * Save stack-backtrace addresses into a stack_trace buffer:
+ */
+static void save_raw_context_stack(struct stack_trace *trace,
+	unsigned long reg29)
+{
+	unsigned long *sp = (unsigned long *)reg29;
+	unsigned long addr;
+
+	while (!kstack_end(sp)) {
+		addr = *sp++;
+		if (__kernel_text_address(addr)) {
+			if (trace->skip > 0)
+				trace->skip--;
+			else
+				trace->entries[trace->nr_entries++] = addr;
+			if (trace->nr_entries >= trace->max_entries)
+				break;
+		}
+	}
+}
+
+static void save_context_stack(struct stack_trace *trace,
+	struct task_struct *task, struct pt_regs *regs)
+{
+	unsigned long sp = regs->regs[29];
+#ifdef CONFIG_KALLSYMS
+	unsigned long ra = regs->regs[31];
+	unsigned long pc = regs->cp0_epc;
+
+	if (raw_show_trace || !__kernel_text_address(pc)) {
+		unsigned long stack_page =
+			(unsigned long)task_stack_page(task);
+		if (stack_page && sp >= stack_page &&
+		    sp <= stack_page + THREAD_SIZE - 32)
+			save_raw_context_stack(trace, sp);
+		return;
+	}
+	do {
+		if (trace->skip > 0)
+			trace->skip--;
+		else
+			trace->entries[trace->nr_entries++] = pc;
+		if (trace->nr_entries >= trace->max_entries)
+			break;
+		pc = unwind_stack(task, &sp, pc, &ra);
+	} while (pc);
+#else
+	save_raw_context_stack(sp);
+#endif
+}
+
+/*
+ * Save stack-backtrace addresses into a stack_trace buffer.
+ */
+void save_stack_trace(struct stack_trace *trace, struct task_struct *task)
+{
+	struct pt_regs dummyregs;
+	struct pt_regs *regs = &dummyregs;
+
+	WARN_ON(trace->nr_entries || !trace->max_entries);
+
+	if (task && task != current) {
+		regs->regs[29] = task->thread.reg29;
+		regs->regs[31] = 0;
+		regs->cp0_epc = task->thread.reg31;
+	} else {
+		if (!task)
+			task = current;
+		prepare_frametrace(regs);
+	}
+
+	save_context_stack(trace, task, regs);
+}
diff --git a/arch/mips/kernel/syscall.c b/arch/mips/kernel/syscall.c
index 9951240cc3f..26e1a7e78d1 100644
--- a/arch/mips/kernel/syscall.c
+++ b/arch/mips/kernel/syscall.c
@@ -231,7 +231,7 @@ out:
  */
 asmlinkage int sys_uname(struct old_utsname __user * name)
 {
-	if (name && !copy_to_user(name, &system_utsname, sizeof (*name)))
+	if (name && !copy_to_user(name, utsname(), sizeof (*name)))
 		return 0;
 	return -EFAULT;
 }
@@ -248,16 +248,21 @@ asmlinkage int sys_olduname(struct oldold_utsname __user * name)
 	if (!access_ok(VERIFY_WRITE,name,sizeof(struct oldold_utsname)))
 		return -EFAULT;
 
-	error = __copy_to_user(&name->sysname,&system_utsname.sysname,__OLD_UTS_LEN);
-	error -= __put_user(0,name->sysname+__OLD_UTS_LEN);
-	error -= __copy_to_user(&name->nodename,&system_utsname.nodename,__OLD_UTS_LEN);
-	error -= __put_user(0,name->nodename+__OLD_UTS_LEN);
-	error -= __copy_to_user(&name->release,&system_utsname.release,__OLD_UTS_LEN);
-	error -= __put_user(0,name->release+__OLD_UTS_LEN);
-	error -= __copy_to_user(&name->version,&system_utsname.version,__OLD_UTS_LEN);
-	error -= __put_user(0,name->version+__OLD_UTS_LEN);
-	error -= __copy_to_user(&name->machine,&system_utsname.machine,__OLD_UTS_LEN);
-	error = __put_user(0,name->machine+__OLD_UTS_LEN);
+	error = __copy_to_user(&name->sysname, &utsname()->sysname,
+			       __OLD_UTS_LEN);
+	error -= __put_user(0, name->sysname + __OLD_UTS_LEN);
+	error -= __copy_to_user(&name->nodename, &utsname()->nodename,
+				__OLD_UTS_LEN);
+	error -= __put_user(0, name->nodename + __OLD_UTS_LEN);
+	error -= __copy_to_user(&name->release, &utsname()->release,
+				__OLD_UTS_LEN);
+	error -= __put_user(0, name->release + __OLD_UTS_LEN);
+	error -= __copy_to_user(&name->version, &utsname()->version,
+				__OLD_UTS_LEN);
+	error -= __put_user(0, name->version + __OLD_UTS_LEN);
+	error -= __copy_to_user(&name->machine, &utsname()->machine,
+				__OLD_UTS_LEN);
+	error = __put_user(0, name->machine + __OLD_UTS_LEN);
 	error = error ? -EFAULT : 0;
 
 	return error;
@@ -401,3 +406,32 @@ asmlinkage void bad_stack(void)
 {
 	do_exit(SIGSEGV);
 }
+
+/*
+ * Do a system call from kernel instead of calling sys_execve so we
+ * end up with proper pt_regs.
+ */
+int kernel_execve(const char *filename, char *const argv[], char *const envp[])
+{
+	register unsigned long __a0 asm("$4") = (unsigned long) filename;
+	register unsigned long __a1 asm("$5") = (unsigned long) argv;
+	register unsigned long __a2 asm("$6") = (unsigned long) envp;
+	register unsigned long __a3 asm("$7");
+	unsigned long __v0;
+
+	__asm__ volatile ("					\n"
+	"	.set	noreorder				\n"
+	"	li	$2, %5		# __NR_execve		\n"
+	"	syscall						\n"
+	"	move	%0, $2					\n"
+	"	.set	reorder					\n"
+	: "=&r" (__v0), "=r" (__a3)
+	: "r" (__a0), "r" (__a1), "r" (__a2), "i" (__NR_execve)
+	: "$2", "$8", "$9", "$10", "$11", "$12", "$13", "$14", "$15", "$24",
+	  "memory");
+
+	if (__a3 == 0)
+		return __v0;
+
+	return -__v0;
+}
diff --git a/arch/mips/kernel/sysirix.c b/arch/mips/kernel/sysirix.c
index 1137dd6ea7a..93c74fefff7 100644
--- a/arch/mips/kernel/sysirix.c
+++ b/arch/mips/kernel/sysirix.c
@@ -884,7 +884,7 @@ asmlinkage int irix_getdomainname(char __user *name, int len)
 	down_read(&uts_sem);
 	if (len > __NEW_UTS_LEN)
 		len = __NEW_UTS_LEN;
-	err = copy_to_user(name, system_utsname.domainname, len) ? -EFAULT : 0;
+	err = copy_to_user(name, utsname()->domainname, len) ? -EFAULT : 0;
 	up_read(&uts_sem);
 
 	return err;
@@ -1127,11 +1127,11 @@ struct iuname {
 asmlinkage int irix_uname(struct iuname __user *buf)
 {
 	down_read(&uts_sem);
-	if (copy_from_user(system_utsname.sysname, buf->sysname, 65)
-	    || copy_from_user(system_utsname.nodename, buf->nodename, 65)
-	    || copy_from_user(system_utsname.release, buf->release, 65)
-	    || copy_from_user(system_utsname.version, buf->version, 65)
-	    || copy_from_user(system_utsname.machine, buf->machine, 65)) {
+	if (copy_from_user(utsname()->sysname, buf->sysname, 65)
+	    || copy_from_user(utsname()->nodename, buf->nodename, 65)
+	    || copy_from_user(utsname()->release, buf->release, 65)
+	    || copy_from_user(utsname()->version, buf->version, 65)
+	    || copy_from_user(utsname()->machine, buf->machine, 65)) {
 		return -EFAULT;
 	}
 	up_read(&uts_sem);
@@ -1739,12 +1739,13 @@ struct irix_dirent32_callback {
 #define ROUND_UP32(x) (((x)+sizeof(u32)-1) & ~(sizeof(u32)-1))
 
 static int irix_filldir32(void *__buf, const char *name,
-	int namlen, loff_t offset, ino_t ino, unsigned int d_type)
+	int namlen, loff_t offset, u64 ino, unsigned int d_type)
 {
 	struct irix_dirent32 __user *dirent;
 	struct irix_dirent32_callback *buf = __buf;
 	unsigned short reclen = ROUND_UP32(NAME_OFFSET32(dirent) + namlen + 1);
 	int err = 0;
+	u32 d_ino;
 
 #ifdef DEBUG_GETDENTS
 	printk("\nirix_filldir32[reclen<%d>namlen<%d>count<%d>]",
@@ -1753,12 +1754,15 @@ static int irix_filldir32(void *__buf, const char *name,
 	buf->error = -EINVAL;	/* only used if we fail.. */
 	if (reclen > buf->count)
 		return -EINVAL;
+	d_ino = ino;
+	if (sizeof(d_ino) < sizeof(ino) && d_ino != ino)
+		return -EOVERFLOW;
 	dirent = buf->previous;
 	if (dirent)
 		err = __put_user(offset, &dirent->d_off);
 	dirent = buf->current_dir;
 	err |= __put_user(dirent, &buf->previous);
-	err |= __put_user(ino, &dirent->d_ino);
+	err |= __put_user(d_ino, &dirent->d_ino);
 	err |= __put_user(reclen, &dirent->d_reclen);
 	err |= copy_to_user((char __user *)dirent->d_name, name, namlen) ? -EFAULT : 0;
 	err |= __put_user(0, &dirent->d_name[namlen]);
@@ -1837,7 +1841,7 @@ struct irix_dirent64_callback {
 #define ROUND_UP64(x) (((x)+sizeof(u64)-1) & ~(sizeof(u64)-1))
 
 static int irix_filldir64(void *__buf, const char *name,
-	int namlen, loff_t offset, ino_t ino, unsigned int d_type)
+	int namlen, loff_t offset, u64 ino, unsigned int d_type)
 {
 	struct irix_dirent64 __user *dirent;
 	struct irix_dirent64_callback * buf = __buf;
diff --git a/arch/mips/kernel/time.c b/arch/mips/kernel/time.c
index 845c7e55505..a8340802f2d 100644
--- a/arch/mips/kernel/time.c
+++ b/arch/mips/kernel/time.c
@@ -149,80 +149,6 @@ void (*mips_timer_ack)(void);
 unsigned int (*mips_hpt_read)(void);
 void (*mips_hpt_init)(unsigned int);
 
-
-/*
- * This version of gettimeofday has microsecond resolution and better than
- * microsecond precision on fast machines with cycle counter.
- */
-void do_gettimeofday(struct timeval *tv)
-{
-	unsigned long seq;
-	unsigned long usec, sec;
-	unsigned long max_ntp_tick;
-
-	do {
-		seq = read_seqbegin(&xtime_lock);
-
-		usec = do_gettimeoffset();
-
-		/*
-		 * If time_adjust is negative then NTP is slowing the clock
-		 * so make sure not to go into next possible interval.
-		 * Better to lose some accuracy than have time go backwards..
-		 */
-		if (unlikely(time_adjust < 0)) {
-			max_ntp_tick = (USEC_PER_SEC / HZ) - tickadj;
-			usec = min(usec, max_ntp_tick);
-		}
-
-		sec = xtime.tv_sec;
-		usec += (xtime.tv_nsec / 1000);
-
-	} while (read_seqretry(&xtime_lock, seq));
-
-	while (usec >= 1000000) {
-		usec -= 1000000;
-		sec++;
-	}
-
-	tv->tv_sec = sec;
-	tv->tv_usec = usec;
-}
-
-EXPORT_SYMBOL(do_gettimeofday);
-
-int do_settimeofday(struct timespec *tv)
-{
-	time_t wtm_sec, sec = tv->tv_sec;
-	long wtm_nsec, nsec = tv->tv_nsec;
-
-	if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC)
-		return -EINVAL;
-
-	write_seqlock_irq(&xtime_lock);
-
-	/*
-	 * This is revolting.  We need to set "xtime" correctly.  However,
-	 * the value in this location is the value at the most recent update
-	 * of wall time.  Discover what correction gettimeofday() would have
-	 * made, and then undo it!
-	 */
-	nsec -= do_gettimeoffset() * NSEC_PER_USEC;
-
-	wtm_sec  = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec);
-	wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec);
-
-	set_normalized_timespec(&xtime, sec, nsec);
-	set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec);
-
-	ntp_clear();
-	write_sequnlock_irq(&xtime_lock);
-	clock_was_set();
-	return 0;
-}
-
-EXPORT_SYMBOL(do_settimeofday);
-
 /*
  * Gettimeoffset routines.  These routines returns the time duration
  * since last timer interrupt in usecs.
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index e51d8fd9a15..b7292a56d4c 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -41,6 +41,7 @@
 #include <asm/mmu_context.h>
 #include <asm/watch.h>
 #include <asm/types.h>
+#include <asm/stacktrace.h>
 
 extern asmlinkage void handle_int(void);
 extern asmlinkage void handle_tlbm(void);
@@ -92,16 +93,14 @@ static void show_raw_backtrace(unsigned long reg29)
 }
 
 #ifdef CONFIG_KALLSYMS
-static int raw_show_trace;
+int raw_show_trace;
 static int __init set_raw_show_trace(char *str)
 {
 	raw_show_trace = 1;
 	return 1;
 }
 __setup("raw_show_trace", set_raw_show_trace);
-
-extern unsigned long unwind_stack(struct task_struct *task, unsigned long *sp,
-				  unsigned long pc, unsigned long ra);
+#endif
 
 static void show_backtrace(struct task_struct *task, struct pt_regs *regs)
 {
@@ -116,14 +115,10 @@ static void show_backtrace(struct task_struct *task, struct pt_regs *regs)
 	printk("Call Trace:\n");
 	do {
 		print_ip_sym(pc);
-		pc = unwind_stack(task, &sp, pc, ra);
-		ra = 0;
+		pc = unwind_stack(task, &sp, pc, &ra);
 	} while (pc);
 	printk("\n");
 }
-#else
-#define show_backtrace(task, r) show_raw_backtrace((r)->regs[29]);
-#endif
 
 /*
  * This routine abuses get_user()/put_user() to reference pointers
@@ -158,28 +153,6 @@ static void show_stacktrace(struct task_struct *task, struct pt_regs *regs)
 	show_backtrace(task, regs);
 }
 
-static __always_inline void prepare_frametrace(struct pt_regs *regs)
-{
-	__asm__ __volatile__(
-		".set push\n\t"
-		".set noat\n\t"
-#ifdef CONFIG_64BIT
-		"1: dla $1, 1b\n\t"
-		"sd $1, %0\n\t"
-		"sd $29, %1\n\t"
-		"sd $31, %2\n\t"
-#else
-		"1: la $1, 1b\n\t"
-		"sw $1, %0\n\t"
-		"sw $29, %1\n\t"
-		"sw $31, %2\n\t"
-#endif
-		".set pop\n\t"
-		: "=m" (regs->cp0_epc),
-		"=m" (regs->regs[29]), "=m" (regs->regs[31])
-		: : "memory");
-}
-
 void show_stack(struct task_struct *task, unsigned long *sp)
 {
 	struct pt_regs regs;
@@ -206,11 +179,6 @@ void dump_stack(void)
 {
 	struct pt_regs regs;
 
-	/*
-	 * Remove any garbage that may be in regs (specially func
-	 * addresses) to avoid show_raw_backtrace() to report them
-	 */
-	memset(&regs, 0, sizeof(regs));
 	prepare_frametrace(&regs);
 	show_backtrace(current, &regs);
 }