o Speedup syscalls. Now 816ns per syscall. Yes, nanoseconds and goodbye

   Pentium :-)
 o Little bit smarter handling of unimplemented exceptions.
 o Fix FPU context switches.
 o Fix reboot / halt.  Powerdown in software still doesn't work.
 o Fix the fix for handling of return values of interrupted syscalls.
 o Handling of the Indy second level cache now works as spec'ed.  Purely
   cosmentic, this was not causing any problems.

9 files changed, 152 insertions, 125 deletions

diff --git a/arch/mips/kernel/entry.S b/arch/mips/kernel/entry.S
index 8abe70182..afabc6156 100644
--- a/arch/mips/kernel/entry.S
+++ b/arch/mips/kernel/entry.S
@@ -7,7 +7,7 @@
  *
  * Copyright (C) 1994, 1995 by Ralf Baechle
  *
- * $Id: entry.S,v 1.6 1998/03/17 22:07:32 ralf Exp $
+ * $Id: entry.S,v 1.10 1998/03/26 07:39:09 ralf Exp $
  */
 
 /*
@@ -40,7 +40,7 @@
 		.set	noreorder
 		.set	mips3
 		.align 4
-handle_bottom_half:
+EXPORT(handle_bottom_half)
 		jal	do_bottom_half
 		 nop
 		b	9f
@@ -96,6 +96,10 @@ LEAF(spurious_interrupt)
  * the C preprocessor ...
  */
 #define __BUILD_clear_none(exception)
+#define __BUILD_clear_sti(exception)                                    \
+		STI
+#define __BUILD_clear_cli(exception)                                    \
+		CLI
 #define __BUILD_clear_fpe(exception)                                    \
 		cfc1	a1,fcr31;                                       \
 		li	a2,~(0x3f<<12);                                 \
@@ -103,7 +107,8 @@ LEAF(spurious_interrupt)
 		ctc1	a2,fcr31;
 #define __BUILD_clear_ade(exception)                                    \
 		MFC0	t0,CP0_BADVADDR;                                \
-		REG_S	t0,PT_BVADDR(sp);
+		REG_S	t0,PT_BVADDR(sp);                               \
+		STI
 #define __BUILD_silent(exception)
 
 #define fmt "Got %s at %08lx.\n"
@@ -129,11 +134,8 @@ EXPORT(exception_count_##exception);                                    \
 		.set	noat;                                           \
 		SAVE_ALL;                                               \
 		__BUILD_clear_##clear(exception);                       \
-		STI;                                                    \
 		.set	at;                                             \
 		__BUILD_##verbose(exception);                           \
-		li	t0,-1;                    /* not a sys call */  \
-		REG_S	t0,PT_OR2(sp);                                  \
 		jal	do_##handler;                                   \
 		 move	a0,sp;                                          \
 		j	ret_from_sys_call;                              \
@@ -142,18 +144,18 @@ EXPORT(exception_count_##exception);                                    \
 
 		BUILD_HANDLER(adel,ade,ade,silent)		/* #4  */
 		BUILD_HANDLER(ades,ade,ade,silent)		/* #5  */
-		BUILD_HANDLER(ibe,ibe,none,verbose)		/* #6  */
-		BUILD_HANDLER(dbe,dbe,none,verbose)		/* #7  */
-		BUILD_HANDLER(bp,bp,none,silent)		/* #9  */
-		BUILD_HANDLER(ri,ri,none,silent)		/* #10 */
-		BUILD_HANDLER(cpu,cpu,none,silent)		/* #11 */
-		BUILD_HANDLER(ov,ov,none,silent)		/* #12 */
-		BUILD_HANDLER(tr,tr,none,silent)		/* #13 */
-		BUILD_HANDLER(vcei,vcei,none,verbose)		/* #14 */
+		BUILD_HANDLER(ibe,ibe,cli,verbose)		/* #6  */
+		BUILD_HANDLER(dbe,dbe,cli,verbose)		/* #7  */
+		BUILD_HANDLER(bp,bp,sti,silent)			/* #9  */
+		BUILD_HANDLER(ri,ri,sti,silent)			/* #10 */
+		BUILD_HANDLER(cpu,cpu,sti,silent)		/* #11 */
+		BUILD_HANDLER(ov,ov,sti,silent)			/* #12 */
+		BUILD_HANDLER(tr,tr,sti,silent)			/* #13 */
+		BUILD_HANDLER(vcei,vcei,sti,verbose)		/* #14 */
 		BUILD_HANDLER(fpe,fpe,fpe,silent)		/* #15 */
-		BUILD_HANDLER(watch,watch,none,verbose)		/* #23 */
-		BUILD_HANDLER(vced,vced,none,verbose)		/* #31 */
-		BUILD_HANDLER(reserved,reserved,none,verbose)	/* others */
+		BUILD_HANDLER(watch,watch,sti,verbose)		/* #23 */
+		BUILD_HANDLER(vced,vced,sti,verbose)		/* #31 */
+		BUILD_HANDLER(reserved,reserved,sti,verbose)	/* others */
 
 /*
  * Table of syscalls
diff --git a/arch/mips/kernel/head.S b/arch/mips/kernel/head.S
index 229f78930..29c326e49 100644
--- a/arch/mips/kernel/head.S
+++ b/arch/mips/kernel/head.S
@@ -8,7 +8,7 @@
  *
  *  Head.S contains the MIPS exception handler and startup code.
  *
- * $Id: head.S,v 1.5 1997/12/01 17:57:27 ralf Exp $
+ * $Id: head.S,v 1.11 1998/03/22 20:43:43 ralf Exp $
  */
 #include <linux/config.h>
 #include <linux/tasks.h>
@@ -396,6 +396,12 @@ probe_done:
 	jal	sgi_sysinit
 	 nop
 #endif
+
+#ifdef CONFIG_COBALT_MICRO_SERVER
+	jal	SetUpBootInfo
+	 nop
+#endif
+
 	/* Get the very one tags we need early in the boot process */
 	nop
 	jal	bi_EarlySnarf
diff --git a/arch/mips/kernel/irixsig.c b/arch/mips/kernel/irixsig.c
index 88fca61f2..d0e286def 100644
--- a/arch/mips/kernel/irixsig.c
+++ b/arch/mips/kernel/irixsig.c
@@ -1,7 +1,9 @@
-/* $Id: irixsig.c,v 1.9 1998/03/17 00:59:35 ralf Exp $
+/*
  * irixsig.c: WHEEE, IRIX signals!  YOW, am I compatable or what?!?!
  *
  * Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
+ *
+ * $Id: irixsig.c,v 1.11 1998/03/26 07:39:09 ralf Exp $
  */
 
 #include <linux/kernel.h>
@@ -154,30 +156,27 @@ static inline void handle_signal(unsigned long sig, struct k_sigaction *ka,
 	}
 }
 
-static inline void syscall_restart(unsigned long r0, unsigned long or2,
-                                   unsigned long or7, struct pt_regs *regs,
-                                   struct sigaction *sa)
+static inline void syscall_restart(struct pt_regs *regs, struct k_sigaction *ka)
 {
-	switch(r0) {
+	switch(regs->regs[0]) {
 	case ERESTARTNOHAND:
-	no_system_call_restart:
-		regs->regs[0] = regs->regs[2] = EINTR;
+		regs->regs[2] = EINTR;
 		break;
 	case ERESTARTSYS:
-		if(!(sa->sa_flags & SA_RESTART))
-			goto no_system_call_restart;
+		if(!(ka->sa.sa_flags & SA_RESTART)) {
+			regs->regs[2] = EINTR;
+			break;
+		}
 	/* fallthrough */
-	case ERESTARTNOINTR:
-		regs->regs[0] = regs->regs[2] = or2;
-		regs->regs[7] = or7;
-	regs->cp0_epc -= 8;
+	case ERESTARTNOINTR:		/* Userland will reload $v0.  */
+		regs->cp0_epc -= 8;
 	}
+
+	regs->regs[0] = 0;		/* Don't deal with this again.  */
 }
 
 asmlinkage int do_irix_signal(sigset_t *oldset, struct pt_regs *regs)
 {
-	unsigned long r0 = regs->regs[0];
-	unsigned long r7 = regs->orig_reg7;
 	struct k_sigaction *ka;
 	siginfo_t info;
 
@@ -279,8 +278,8 @@ asmlinkage int do_irix_signal(sigset_t *oldset, struct pt_regs *regs)
 			}
 		}
 
-		if (r0)
-			syscall_restart(r0, regs->orig_reg2, r7, regs, &ka->sa);
+		if (regs->regs[0])
+			syscall_restart(regs, ka);
 		/* Whee!  Actually deliver the signal.  */
 		handle_signal(signr, ka, &info, oldset, regs);
 		return 1;
@@ -291,13 +290,12 @@ asmlinkage int do_irix_signal(sigset_t *oldset, struct pt_regs *regs)
 	 * dies here!!!  The li instruction, a single machine instruction,
 	 * must directly be followed by the syscall instruction.
 	 */
-	if (r0 &&
-	    (regs->regs[2] == ERESTARTNOHAND ||
-	     regs->regs[2] == ERESTARTSYS ||
-	     regs->regs[2] == ERESTARTNOINTR)) {
-		regs->regs[0] = regs->regs[2] = regs->orig_reg2;
-		regs->regs[7] = r7;
-		regs->cp0_epc -= 8;
+	if (regs->regs[0]) {
+		if (regs->regs[2] == ERESTARTNOHAND ||
+		    regs->regs[2] == ERESTARTSYS ||
+		    regs->regs[2] == ERESTARTNOINTR) {
+			regs->cp0_epc -= 8;
+		}
 	}
 	return 0;
 }
@@ -356,10 +354,15 @@ asmlinkage unsigned long irix_sigreturn(struct pt_regs *regs)
 	recalc_sigpending(current);
 	spin_unlock_irq(&current->sigmask_lock);
 
-	regs->orig_reg2 = -1;
-	__get_user(res, &context->regs[2]);
-
-	return res;
+	/*
+	 * Don't let your children do this ...
+	 */
+	__asm__ __volatile__(
+		"move\t$29,%0\n\t"
+		"j\tret_from_sys_call"
+		:/* no outputs */
+		:"r" (&regs));
+		/* Unreached */
 
 badframe:
 	lock_kernel();
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
index 4b65d3c97..45d58730c 100644
--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -7,7 +7,7 @@
  *
  * Copyright (C) 1994 - 1998 by Ralf Baechle and others.
  *
- * $Id: process.c,v 1.5 1998/03/22 23:27:13 ralf Exp $
+ * $Id: process.c,v 1.7 1998/03/22 20:43:43 ralf Exp $
  */
 #include <linux/config.h>
 #include <linux/errno.h>
diff --git a/arch/mips/kernel/r2300_switch.S b/arch/mips/kernel/r2300_switch.S
index 7efd61927..f4470e54d 100644
--- a/arch/mips/kernel/r2300_switch.S
+++ b/arch/mips/kernel/r2300_switch.S
@@ -1,10 +1,12 @@
-/* $Id: r2300_switch.S,v 1.1.1.1 1997/06/01 03:16:43 ralf Exp $
+/*
  * r2300_switch.S: R3000/R2000 specific task switching code.
  *
  * Copyright (C) 1994, 1995, 1996 by Ralf Baechle and Andreas Busse
  *
  * Multi-cpu abstraction and macros for easier reading:
  * Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
+ *
+ * $Id: r2300_switch.S,v 1.3 1998/03/23 06:34:37 ralf Exp $
  */
 #include <asm/asm.h>
 #include <asm/bootinfo.h>
@@ -25,7 +27,8 @@
 MODE_ALIAS	=	0x00e0			# uncachable, dirty, valid
 
 	.text
-	.set	mips3
+	.set	mips1
+	.set	noreorder
 /*
  * Code necessary to switch tasks on an Linux/MIPS machine.
  * FIXME: We don't need to disable interrupts anymore.
@@ -39,15 +42,10 @@ MODE_ALIAS	=	0x00e0			# uncachable, dirty, valid
 	mtc0	t2,CP0_STATUS
 	CPU_SAVE_NONSCRATCH($28)
 	sll	t2,t1,2			# Save floating point state
-	bgez	t2,2f
-	 sw	ra,THREAD_REG31($28)
-	sll	t2,t1,5
 	bgez	t2,1f
-	 swc1	$f0, (THREAD_FPU + 0x00)($28)
-	FPU_SAVE_16ODD($28)
+	 sw	ra,THREAD_REG31($28)
+	FPU_SAVE($28, t0)
 1:
-	FPU_SAVE_16EVEN($28, t1)
-2:
 	move	$28, a0
 	lw	t0,THREAD_PGDIR($28)	# Switch the root pointer
 	li	t1,TLB_ROOT		# get PFN
@@ -80,14 +78,10 @@ MODE_ALIAS	=	0x00e0			# uncachable, dirty, valid
 	xori	t1,1
 	mtc0	t1,CP0_STATUS
 	sll	t0,a2,2
-	bgez	t0,2f
-	 sll	t0,a2,5
 	bgez	t0,1f
-	 lwc1	$f0, (THREAD_FPU + 0x00)($28)
-	FPU_RESTORE_16ODD($28)
+	 lw	ra,THREAD_REG31($28)
+	FPU_RESTORE($28, t0)
 1:
-	FPU_RESTORE_16EVEN($28, t0)
-2:
 	CPU_RESTORE_NONSCRATCH($28)
 	lw	t0,THREAD_KSP($28)		# Restore status register
 	sw	t0,kernelsp
diff --git a/arch/mips/kernel/scall_o32.S b/arch/mips/kernel/scall_o32.S
index eb25c34e5..6c46dedda 100644
--- a/arch/mips/kernel/scall_o32.S
+++ b/arch/mips/kernel/scall_o32.S
@@ -1,9 +1,13 @@
 /*
- * Handle ABI O32 style syscalls.
+ * arch/mips/kernel/scall_o32.S
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
  *
  * Copyright (C) 1997, 1998 by Ralf Baechle
  *
- * $Id: scall_o32.S,v 1.1 1998/03/12 19:06:20 ralf Exp $
+ * $Id: scall_o32.S,v 1.3 1998/03/26 07:39:10 ralf Exp $
  */
 #include <asm/asm.h>
 #include <linux/errno.h>
@@ -25,18 +29,11 @@
 	.align  5
 NESTED(handle_sys, PT_SIZE, sp)
 	.set	noat
-	SAVE_ALL
+	SAVE_SOME
 	STI
 	.set	at
 
-	/*
-	 * By convention "li v0,<syscallno>" is always preceeding
-	 * the syscall instruction.  So if we're in a delay slot
-	 * userland is screwed up.
-	 */
-	lw	t0, PT_CAUSE(sp)	# delay slot?
 	lw	t1, PT_EPC(sp)		# skip syscall on return
-	bltz	t0, sigill_and_out
 
 	sltiu	t0, v0, MAX_SYSCALL_NO + 1 # check syscall number
 	addiu	t1, 4			# skip to next instruction
@@ -45,18 +42,19 @@ NESTED(handle_sys, PT_SIZE, sp)
 
 	/* XXX Put both in one cacheline, should save a bit. */
 	sll	t0, v0, 2
-	lw	s0, sys_call_table(t0)	# syscall routine
-	lbu	s1, sys_narg_table(v0)	# number of arguments
-	beqz	s0, illegal_syscall;
+	lw	t2, sys_call_table(t0)	# syscall routine
+	lbu	t3, sys_narg_table(v0)	# number of arguments
+	beqz	t2, illegal_syscall;
 
-	subu	t0, s1, 5		# 5 or more arguments?
-	bgezal	t0, stackargs
+	subu	t0, t3, 5		# 5 or more arguments?
+	bgez	t0, stackargs
 
-	lw	s3, TASK_FLAGS($28)	# syscall tracing enabled?
-	andi	s3, PF_TRACESYS
-	bnez	s3, trace_a_syscall
+stack_done:
+	lw	t0, TASK_FLAGS($28)	# syscall tracing enabled?
+	andi	t0, PF_TRACESYS
+	bnez	t0, trace_a_syscall
 
-	jalr	s0			# Do The Real Thing (TM)
+	jalr	t2			# Do The Real Thing (TM)
 
 	li	t0, -EMAXERRNO - 1	# error?
 	sltu	t0, t0, v0
@@ -66,14 +64,49 @@ NESTED(handle_sys, PT_SIZE, sp)
 	negu	v0			# error
 	sw	v0, PT_R0(sp)		# set flag for syscall restarting
 1:	sw	v0, PT_R2(sp)		# result
-	j	ret_from_sys_call
+
+EXPORT(o32_ret_from_sys_call)
+	lw	t0,bh_mask
+	lw	t1,bh_active		# unused delay slot
+	and	t0,t1
+	bnez	t0,o32_handle_bottom_half
+
+9:	lw	t0,PT_STATUS(sp)	# returning to kernel mode?
+	andi	t1, t0, 0x10
+	lw	t2, need_resched
+	beqz	t1, o32_return		# -> yes
+	bnez	t2, o32_reschedule
+	lw	v0, TASK_SIGPENDING($28)
+	move	a0, zero
+	beqz	v0, o32_return
+	move	a1, sp
+	SAVE_STATIC
+	jal	do_signal
+
+o32_return:
+	RESTORE_SOME
+	RESTORE_SP
+	.set	mips3
+	eret
+	.set	mips0
+
+o32_handle_bottom_half:
+	jal	do_bottom_half
+	b	9b
+o32_reschedule:
+	SAVE_STATIC
+	jal	schedule
+	b	o32_ret_from_sys_call
 
 /* ------------------------------------------------------------------------ */
 
 trace_a_syscall:
+	SAVE_STATIC
+	sw	t2,PT_R1(sp)
 	jal	syscall_trace
+	sw	t2,PT_R1(sp)
 
-	jalr	s0			# Do The Real Thing (TM)
+	jalr	t2			# Do The Real Thing (TM)
 
 	li	t0, -EMAXERRNO - 1	# error?
 	sltu	t0, t0, v0
@@ -95,20 +128,18 @@ trace_a_syscall:
 	 * This Sucks (TM).
 	 */
 stackargs:
-	move	s3, ra			# save return address
-
 	lw	t0, PT_R29(sp)		# get old user stack pointer
-	subu	s2, s1, 4
-	sll	t1, s2, 2		# stack valid?
+	subu	t3, 4
+	sll	t1, t3, 2		# stack valid?
 
 	addu	t1, t0			# end address
-	or	t2, t0, t1
+	or	t0, t1
 	bltz	t0, bad_stack		# -> sp is bad
 
 	lw	t0, PT_R29(sp)		# get old user stack pointer
 	la	t1, 3f			# copy 1 to 2 arguments
-	sll	s2, s2, 3
-	subu	t1, s2
+	sll	t3, t3, 3
+	subu	t1, t3
 	jr	t1
 
 	/* Ok, copy the args from the luser stack to the kernel stack */
@@ -117,7 +148,7 @@ stackargs:
 2:	lw	t1, 16(t0)		# argument #5 from usp
 	sw	t1, 16(sp)
 
-3:	jr	s3			# go back
+3:	j	stack_done		# go back
 
 	.section __ex_table,"a"
 	PTR	1b,bad_stack
@@ -144,12 +175,3 @@ illegal_syscall:
 	li	t0, 1				# set error flag
 	sw	t0, PT_R7(sp)
 	j	ret_from_sys_call
-
-sigill_and_out:
-	li	t0, -1				# not a sys call
-	REG_S	t0, PT_OR2(sp)
-	li	a0, SIGILL
-	move	a2, $28
-	jal	force_sig
-	j	ret_from_sys_call
-	END(handle_sys)
diff --git a/arch/mips/kernel/signal.c b/arch/mips/kernel/signal.c
index 0e7a24766..007e95452 100644
--- a/arch/mips/kernel/signal.c
+++ b/arch/mips/kernel/signal.c
@@ -4,7 +4,7 @@
  *  Copyright (C) 1991, 1992  Linus Torvalds
  *  Copyright (C) 1994, 1995, 1996  Ralf Baechle
  *
- * $Id: signal.c,v 1.9 1998/03/17 22:07:36 ralf Exp $
+ * $Id: signal.c,v 1.17 1998/03/26 07:39:10 ralf Exp $
  */
 #include <linux/config.h>
 #include <linux/sched.h>
@@ -203,11 +203,6 @@ asmlinkage int sys_sigreturn(struct pt_regs regs)
 	restore_sigcontext(&regs, context);
 
 	/*
-	 * Disable syscall checks
-	 */
-	regs.orig_reg2 = -1;
-
-	/*
 	 * Don't let your children do this ...
 	 */
 	__asm__ __volatile__(
@@ -347,30 +342,29 @@ static inline void handle_signal(unsigned long sig, struct k_sigaction *ka,
 	}
 }
 
-static inline void syscall_restart(unsigned long or2, unsigned long or7,
-                                   struct pt_regs *regs, struct sigaction *sa)
+static inline void syscall_restart(struct pt_regs *regs, struct k_sigaction *ka)
 {
 	switch(regs->regs[0]) {
 	case ERESTARTNOHAND:
-	no_system_call_restart:
-		regs->regs[0] = regs->regs[2] = EINTR;
+		regs->regs[2] = EINTR;
 		break;
 	case ERESTARTSYS:
-		if(!(sa->sa_flags & SA_RESTART))
-			goto no_system_call_restart;
+		if(!(ka->sa.sa_flags & SA_RESTART)) {
+			regs->regs[2] = EINTR;
+			break;
+		}
 	/* fallthrough */
-	case ERESTARTNOINTR:
-		regs->regs[0] = regs->regs[2] = or2;
-		regs->regs[7] = or7;
+	case ERESTARTNOINTR:		/* Userland will reload $v0.  */
 		regs->cp0_epc -= 8;
 	}
+
+	regs->regs[0] = 0;		/* Don't deal with this again.  */
 }
 
 extern int do_irix_signal(sigset_t *oldset, struct pt_regs *regs);
 
 asmlinkage int do_signal(sigset_t *oldset, struct pt_regs *regs)
 {
-	unsigned long r7 = regs->orig_reg7;
 	struct k_sigaction *ka;
 	siginfo_t info;
 
@@ -478,7 +472,7 @@ asmlinkage int do_signal(sigset_t *oldset, struct pt_regs *regs)
 		}
 
 		if (regs->regs[0])
-			syscall_restart(regs->orig_reg2, r7, regs, &ka->sa);
+			syscall_restart(regs, ka);
 		/* Whee!  Actually deliver the signal.  */
 		handle_signal(signr, ka, &info, oldset, regs);
 		return 1;
@@ -493,9 +487,7 @@ asmlinkage int do_signal(sigset_t *oldset, struct pt_regs *regs)
 		if (regs->regs[2] == ERESTARTNOHAND ||
 		    regs->regs[2] == ERESTARTSYS ||
 		    regs->regs[2] == ERESTARTNOINTR) {
-		regs->regs[0] = regs->regs[2] = regs->orig_reg2;
-		regs->regs[7] = r7;
-		regs->cp0_epc -= 8;
+			regs->cp0_epc -= 8;
 		}
 	}
 	return 0;
diff --git a/arch/mips/kernel/syscall.c b/arch/mips/kernel/syscall.c
index ac5cd123b..4781e790b 100644
--- a/arch/mips/kernel/syscall.c
+++ b/arch/mips/kernel/syscall.c
@@ -11,7 +11,7 @@
  *        Don't waste that much memory for empty entries in the syscall
  *        table.
  *
- * $Id: syscall.c,v 1.6 1998/03/17 22:07:36 ralf Exp $
+ * $Id: syscall.c,v 1.8 1998/03/26 07:39:10 ralf Exp $
  */
 #undef CONF_PRINT_SYSCALLS
 #undef CONF_DEBUG_IRIX
@@ -27,8 +27,10 @@
 #include <linux/utsname.h>
 #include <linux/unistd.h>
 #include <asm/branch.h>
+#include <asm/offset.h>
 #include <asm/ptrace.h>
 #include <asm/signal.h>
+#include <asm/stackframe.h>
 #include <asm/uaccess.h>
 
 extern asmlinkage void syscall_trace(void);
@@ -113,6 +115,7 @@ asmlinkage int sys_fork(struct pt_regs regs)
 {
 	int res;
 
+	save_static(&regs);
 	lock_kernel();
 	res = do_fork(SIGCHLD, regs.regs[29], &regs);
 	unlock_kernel();
@@ -125,6 +128,7 @@ asmlinkage int sys_clone(struct pt_regs regs)
 	unsigned long newsp;
 	int res;
 
+	save_static(&regs);
 	lock_kernel();
 	clone_flags = regs.regs[4];
 	newsp = regs.regs[5];
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index f2ad107fa..629a07836 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -8,7 +8,7 @@
  * Copyright 1994, 1995, 1996, 1997 by Ralf Baechle
  * Modified for R3000 by Paul M. Antoine, 1995, 1996
  *
- * $Id: traps.c,v 1.7 1998/03/17 22:07:38 ralf Exp $
+ * $Id: traps.c,v 1.12 1998/03/26 07:39:11 ralf Exp $
  */
 #include <linux/config.h>
 #include <linux/init.h>
@@ -183,6 +183,7 @@ static void default_be_board_handler(struct pt_regs *regs)
 void do_ibe(struct pt_regs *regs)
 {
 	lock_kernel();
+show_regs(regs); while(1);
 	ibe_board_handler(regs);
 	unlock_kernel();
 }
@@ -190,6 +191,7 @@ void do_ibe(struct pt_regs *regs)
 void do_dbe(struct pt_regs *regs)
 {
 	lock_kernel();
+show_regs(regs); while(1);
 	dbe_board_handler(regs);
 	unlock_kernel();
 }
@@ -240,11 +242,11 @@ void do_fpe(struct pt_regs *regs, unsigned long fcr31)
 	show_regs(regs);
 #endif
 	if (fcr31 & 0x20000) {
-		printk("Unimplemented exception at 0x%08lx in %s.\n",
-		       regs->cp0_epc, current->comm);
 		/* Retry instruction with flush to zero ...  */
 		if (!(fcr31 & (1<<24))) {
-			printk("Setting flush to zero ...\n");
+			printk("Setting flush to zero for %s.\n",
+			       current->comm);
+			fcr31 &= ~0x20000;
 			fcr31 |= (1<<24);
 			__asm__ __volatile__(
 				"ctc1\t%0,$31"
@@ -252,6 +254,8 @@ void do_fpe(struct pt_regs *regs, unsigned long fcr31)
 				: "r" (fcr31));
 			goto out;
 		}
+		printk("Unimplemented exception at 0x%08lx in %s.\n",
+		       regs->cp0_epc, current->comm);
 	}
 	if (compute_return_epc(regs))
 		goto out;