Merge tag 'for-linus' of https://github.com/openrisc/linux

Pull OpenRISC updates from Stafford Horne:
 "A few cleanups and fixups from me:

   - Add a few missing relocations to fix module loading

   - Cleanup FPU state save and restore to be more efficient

   - Cleanups to traps handling and logging

   - Fix issue with poweroff being broken after recent power driver
     refactorings"

* tag 'for-linus' of https://github.com/openrisc/linux:
  openrisc: Move FPU state out of pt_regs
  openrisc: Add FPU config
  openrisc: traps: Don't send signals to kernel mode threads
  openrisc: traps: Remove calls to show_registers before die
  openrisc: traps: Convert printks to pr_<level> macros
  openrisc: Add support for more module relocations
  openrisc: Define openrisc relocation types
  openrisc: Use do_kernel_power_off()

arch/openrisc/Kconfig

@@ -188,6 +188,15 @@ config SMP
 
 	  If you don't know what to do here, say N.
 
+config FPU
+	bool "FPU support"
+	default y
+	help
+	  Say N here if you want to disable all floating-point related procedures
+	  in the kernel and reduce binary size.
+
+	  If you don't know what to do here, say Y.
+
 source "kernel/Kconfig.hz"
 
 config OPENRISC_NO_SPR_SR_DSX

arch/openrisc/include/asm/fpu.h

+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ASM_OPENRISC_FPU_H
+#define __ASM_OPENRISC_FPU_H
+
+struct task_struct;
+
+#ifdef CONFIG_FPU
+static inline void save_fpu(struct task_struct *task)
+{
+	task->thread.fpcsr = mfspr(SPR_FPCSR);
+}
+
+static inline void restore_fpu(struct task_struct *task)
+{
+	mtspr(SPR_FPCSR, task->thread.fpcsr);
+}
+#else
+#define save_fpu(tsk)			do { } while (0)
+#define restore_fpu(tsk)		do { } while (0)
+#endif
+
+#endif /* __ASM_OPENRISC_FPU_H */

arch/openrisc/include/asm/processor.h

@@ -44,6 +44,7 @@
 struct task_struct;
 
 struct thread_struct {
+	long fpcsr;		/* Floating point control status register. */
 };
 
 /*

arch/openrisc/include/asm/ptrace.h

@@ -59,7 +59,7 @@ struct pt_regs {
 	 * -1 for all other exceptions.
 	 */
 	long  orig_gpr11;	/* For restarting system calls */
-	long fpcsr;		/* Floating point control status register. */
+	long dummy;		/* Cheap alignment fix */
 	long dummy2;		/* Cheap alignment fix */
 };
 
@@ -115,6 +115,5 @@ static inline long regs_return_value(struct pt_regs *regs)
 #define PT_GPR31      124
 #define PT_PC	      128
 #define PT_ORIG_GPR11 132
-#define PT_FPCSR      136
 
 #endif /* __ASM_OPENRISC_PTRACE_H */

arch/openrisc/include/uapi/asm/elf.h

@@ -34,15 +34,72 @@
 #include <asm/ptrace.h>
 
 /* The OR1K relocation types... not all relevant for module loader */
-#define R_OR32_NONE	0
-#define R_OR32_32	1
-#define R_OR32_16	2
-#define R_OR32_8	3
-#define R_OR32_CONST	4
-#define R_OR32_CONSTH	5
-#define R_OR32_JUMPTARG	6
-#define R_OR32_VTINHERIT 7
-#define R_OR32_VTENTRY	8
+#define R_OR1K_NONE		0
+#define R_OR1K_32		1
+#define R_OR1K_16		2
+#define R_OR1K_8		3
+#define R_OR1K_LO_16_IN_INSN	4
+#define R_OR1K_HI_16_IN_INSN	5
+#define R_OR1K_INSN_REL_26	6
+#define R_OR1K_GNU_VTENTRY	7
+#define R_OR1K_GNU_VTINHERIT	8
+#define R_OR1K_32_PCREL		9
+#define R_OR1K_16_PCREL		10
+#define R_OR1K_8_PCREL		11
+#define R_OR1K_GOTPC_HI16	12
+#define R_OR1K_GOTPC_LO16	13
+#define R_OR1K_GOT16		14
+#define R_OR1K_PLT26		15
+#define R_OR1K_GOTOFF_HI16	16
+#define R_OR1K_GOTOFF_LO16	17
+#define R_OR1K_COPY		18
+#define R_OR1K_GLOB_DAT		19
+#define R_OR1K_JMP_SLOT		20
+#define R_OR1K_RELATIVE		21
+#define R_OR1K_TLS_GD_HI16	22
+#define R_OR1K_TLS_GD_LO16	23
+#define R_OR1K_TLS_LDM_HI16	24
+#define R_OR1K_TLS_LDM_LO16	25
+#define R_OR1K_TLS_LDO_HI16	26
+#define R_OR1K_TLS_LDO_LO16	27
+#define R_OR1K_TLS_IE_HI16	28
+#define R_OR1K_TLS_IE_LO16	29
+#define R_OR1K_TLS_LE_HI16	30
+#define R_OR1K_TLS_LE_LO16	31
+#define R_OR1K_TLS_TPOFF	32
+#define R_OR1K_TLS_DTPOFF	33
+#define R_OR1K_TLS_DTPMOD	34
+#define R_OR1K_AHI16		35
+#define R_OR1K_GOTOFF_AHI16	36
+#define R_OR1K_TLS_IE_AHI16	37
+#define R_OR1K_TLS_LE_AHI16	38
+#define R_OR1K_SLO16		39
+#define R_OR1K_GOTOFF_SLO16	40
+#define R_OR1K_TLS_LE_SLO16	41
+#define R_OR1K_PCREL_PG21	42
+#define R_OR1K_GOT_PG21		43
+#define R_OR1K_TLS_GD_PG21	44
+#define R_OR1K_TLS_LDM_PG21	45
+#define R_OR1K_TLS_IE_PG21	46
+#define R_OR1K_LO13		47
+#define R_OR1K_GOT_LO13		48
+#define R_OR1K_TLS_GD_LO13	49
+#define R_OR1K_TLS_LDM_LO13	50
+#define R_OR1K_TLS_IE_LO13	51
+#define R_OR1K_SLO13		52
+#define R_OR1K_PLTA26		53
+#define R_OR1K_GOT_AHI16	54
+
+/* Old relocation names */
+#define R_OR32_NONE	R_OR1K_NONE
+#define R_OR32_32	R_OR1K_32
+#define R_OR32_16	R_OR1K_16
+#define R_OR32_8	R_OR1K_8
+#define R_OR32_CONST	R_OR1K_LO_16_IN_INSN
+#define R_OR32_CONSTH	R_OR1K_HI_16_IN_INSN
+#define R_OR32_JUMPTARG	R_OR1K_INSN_REL_26
+#define R_OR32_VTENTRY	R_OR1K_GNU_VTENTRY
+#define R_OR32_VTINHERIT R_OR1K_GNU_VTINHERIT
 
 typedef unsigned long elf_greg_t;
 

arch/openrisc/kernel/entry.S

@@ -106,8 +106,6 @@
 	l.mtspr r0,r3,SPR_EPCR_BASE				;\
 	l.lwz   r3,PT_SR(r1)					;\
 	l.mtspr r0,r3,SPR_ESR_BASE				;\
-	l.lwz	r3,PT_FPCSR(r1)					;\
-	l.mtspr	r0,r3,SPR_FPCSR					;\
 	l.lwz   r2,PT_GPR2(r1)					;\
 	l.lwz   r3,PT_GPR3(r1)					;\
 	l.lwz   r4,PT_GPR4(r1)					;\
@@ -177,8 +175,6 @@ handler:							;\
 	/* r30 already save */					;\
 	l.sw    PT_GPR31(r1),r31					;\
 	TRACE_IRQS_OFF_ENTRY						;\
-	l.mfspr	r30,r0,SPR_FPCSR				;\
-	l.sw	PT_FPCSR(r1),r30				;\
 	/* Store -1 in orig_gpr11 for non-syscall exceptions */	;\
 	l.addi	r30,r0,-1					;\
 	l.sw	PT_ORIG_GPR11(r1),r30
@@ -219,8 +215,6 @@ handler:							;\
 	/* Store -1 in orig_gpr11 for non-syscall exceptions */	;\
 	l.addi	r30,r0,-1					;\
 	l.sw	PT_ORIG_GPR11(r1),r30				;\
-	l.mfspr	r30,r0,SPR_FPCSR				;\
-	l.sw	PT_FPCSR(r1),r30				;\
 	l.addi	r3,r1,0						;\
 	/* r4 is exception EA */				;\
 	l.addi	r5,r0,vector					;\
@@ -852,6 +846,7 @@ _syscall_badsys:
 
 EXCEPTION_ENTRY(_fpe_trap_handler)
 	CLEAR_LWA_FLAG(r3)
+
 	/* r4: EA of fault (set by EXCEPTION_HANDLE) */
 	l.jal   do_fpe_trap
 	 l.addi  r3,r1,0 /* pt_regs */
@@ -1100,10 +1095,6 @@ ENTRY(_switch)
 	l.sw    PT_GPR28(r1),r28
 	l.sw    PT_GPR30(r1),r30
 
-	/* Store the old FPU state to new pt_regs */
-	l.mfspr	r29,r0,SPR_FPCSR
-	l.sw	PT_FPCSR(r1),r29
-
 	l.addi	r11,r10,0			/* Save old 'current' to 'last' return value*/
 
 	/* We use thread_info->ksp for storing the address of the above
@@ -1126,10 +1117,6 @@ ENTRY(_switch)
 	l.lwz	r29,PT_SP(r1)
 	l.sw	TI_KSP(r10),r29
 
-	/* Restore the old value of FPCSR */
-	l.lwz	r29,PT_FPCSR(r1)
-	l.mtspr	r0,r29,SPR_FPCSR
-
 	/* ...and restore the registers, except r11 because the return value
 	 * has already been set above.
 	 */

arch/openrisc/kernel/module.c

@@ -39,22 +39,32 @@ int apply_relocate_add(Elf32_Shdr *sechdrs,
 		value = sym->st_value + rel[i].r_addend;
 
 		switch (ELF32_R_TYPE(rel[i].r_info)) {
-		case R_OR32_32:
+		case R_OR1K_32:
 			*location = value;
 			break;
-		case R_OR32_CONST:
+		case R_OR1K_LO_16_IN_INSN:
 			*((uint16_t *)location + 1) = value;
 			break;
-		case R_OR32_CONSTH:
+		case R_OR1K_HI_16_IN_INSN:
 			*((uint16_t *)location + 1) = value >> 16;
 			break;
-		case R_OR32_JUMPTARG:
+		case R_OR1K_INSN_REL_26:
 			value -= (uint32_t)location;
 			value >>= 2;
 			value &= 0x03ffffff;
 			value |= *location & 0xfc000000;
 			*location = value;
 			break;
+		case R_OR1K_AHI16:
+			/* Adjust the operand to match with a signed LO16.  */
+			value += 0x8000;
+			*((uint16_t *)location + 1) = value >> 16;
+			break;
+		case R_OR1K_SLO16:
+			/* Split value lower 16-bits.  */
+			value = ((value & 0xf800) << 10) | (value & 0x7ff);
+			*location = (*location & ~0x3e007ff) | value;
+			break;
 		default:
 			pr_err("module %s: Unknown relocation: %u\n",
 			       me->name, ELF32_R_TYPE(rel[i].r_info));

arch/openrisc/kernel/process.c

@@ -36,6 +36,7 @@
 #include <linux/reboot.h>
 
 #include <linux/uaccess.h>
+#include <asm/fpu.h>
 #include <asm/io.h>
 #include <asm/processor.h>
 #include <asm/spr_defs.h>
@@ -65,7 +66,7 @@ void machine_restart(char *cmd)
 }
 
 /*
- * This is used if pm_power_off has not been set by a power management
+ * This is used if a sys-off handler was not set by a power management
  * driver, in this case we can assume we are on a simulator.  On
  * OpenRISC simulators l.nop 1 will trigger the simulator exit.
  */
@@ -89,9 +90,7 @@ void machine_halt(void)
 void machine_power_off(void)
 {
 	printk(KERN_INFO "*** MACHINE POWER OFF ***\n");
-	if (pm_power_off != NULL)
-		pm_power_off();
-	else
+	do_kernel_power_off();
 	default_power_off();
 }
 
@@ -246,6 +245,8 @@ struct task_struct *__switch_to(struct task_struct *old,
 
 	local_irq_save(flags);
 
+	save_fpu(current);
+
 	/* current_set is an array of saved current pointers
 	 * (one for each cpu). we need them at user->kernel transition,
 	 * while we save them at kernel->user transition
@@ -258,6 +259,8 @@ struct task_struct *__switch_to(struct task_struct *old,
 	current_thread_info_set[smp_processor_id()] = new_ti;
 	last = (_switch(old_ti, new_ti))->task;
 
+	restore_fpu(current);
+
 	local_irq_restore(flags);
 
 	return last;

arch/openrisc/kernel/ptrace.c

@@ -88,6 +88,7 @@ static int genregs_set(struct task_struct *target,
 	return ret;
 }
 
+#ifdef CONFIG_FPU
 /*
  * As OpenRISC shares GPRs and floating point registers we don't need to export
  * the floating point registers again.  So here we only export the fpcsr special
@@ -97,9 +98,7 @@ static int fpregs_get(struct task_struct *target,
 		       const struct user_regset *regset,
 		       struct membuf to)
 {
-	const struct pt_regs *regs = task_pt_regs(target);
-
-	return membuf_store(&to, regs->fpcsr);
+	return membuf_store(&to, target->thread.fpcsr);
 }
 
 static int fpregs_set(struct task_struct *target,
@@ -107,21 +106,20 @@ static int fpregs_set(struct task_struct *target,
 		       unsigned int pos, unsigned int count,
 		       const void *kbuf, const void __user *ubuf)
 {
-	struct pt_regs *regs = task_pt_regs(target);
-	int ret;
-
 	/* FPCSR */
-	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
-				 &regs->fpcsr, 0, 4);
-	return ret;
+	return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+				  &target->thread.fpcsr, 0, 4);
 }
+#endif
 
 /*
  * Define the register sets available on OpenRISC under Linux
  */
 enum or1k_regset {
 	REGSET_GENERAL,
+#ifdef CONFIG_FPU
 	REGSET_FPU,
+#endif
 };
 
 static const struct user_regset or1k_regsets[] = {
@@ -133,6 +131,7 @@ static const struct user_regset or1k_regsets[] = {
 			    .regset_get = genregs_get,
 			    .set = genregs_set,
 			    },
+#ifdef CONFIG_FPU
 	[REGSET_FPU] = {
 			    .core_note_type = NT_PRFPREG,
 			    .n = sizeof(struct __or1k_fpu_state) / sizeof(long),
@@ -141,6 +140,7 @@ static const struct user_regset or1k_regsets[] = {
 			    .regset_get = fpregs_get,
 			    .set = fpregs_set,
 			    },
+#endif
 };
 
 static const struct user_regset_view user_or1k_native_view = {

arch/openrisc/kernel/signal.c

@@ -23,6 +23,7 @@
 #include <linux/stddef.h>
 #include <linux/resume_user_mode.h>
 
+#include <asm/fpu.h>
 #include <asm/processor.h>
 #include <asm/syscall.h>
 #include <asm/ucontext.h>
@@ -39,6 +40,37 @@ asmlinkage long _sys_rt_sigreturn(struct pt_regs *regs);
 asmlinkage int do_work_pending(struct pt_regs *regs, unsigned int thread_flags,
 			       int syscall);
 
+#ifdef CONFIG_FPU
+static long restore_fp_state(struct sigcontext __user *sc)
+{
+	long err;
+
+	err = __copy_from_user(&current->thread.fpcsr, &sc->fpcsr, sizeof(unsigned long));
+	if (unlikely(err))
+		return err;
+
+	/* Restore the FPU state */
+	restore_fpu(current);
+
+	return 0;
+}
+
+static long save_fp_state(struct sigcontext __user *sc)
+{
+	long err;
+
+	/* Sync the user FPU state so we can copy to sigcontext */
+	save_fpu(current);
+
+	err = __copy_to_user(&sc->fpcsr, &current->thread.fpcsr, sizeof(unsigned long));
+
+	return err;
+}
+#else
+#define save_fp_state(sc) (0)
+#define restore_fp_state(sc) (0)
+#endif
+
 static int restore_sigcontext(struct pt_regs *regs,
 			      struct sigcontext __user *sc)
 {
@@ -55,7 +87,7 @@ static int restore_sigcontext(struct pt_regs *regs,
 	err |= __copy_from_user(regs, sc->regs.gpr, 32 * sizeof(unsigned long));
 	err |= __copy_from_user(&regs->pc, &sc->regs.pc, sizeof(unsigned long));
 	err |= __copy_from_user(&regs->sr, &sc->regs.sr, sizeof(unsigned long));
-	err |= __copy_from_user(&regs->fpcsr, &sc->fpcsr, sizeof(unsigned long));
+	err |= restore_fp_state(sc);
 
 	/* make sure the SM-bit is cleared so user-mode cannot fool us */
 	regs->sr &= ~SPR_SR_SM;
@@ -118,7 +150,7 @@ static int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
 	err |= __copy_to_user(sc->regs.gpr, regs, 32 * sizeof(unsigned long));
 	err |= __copy_to_user(&sc->regs.pc, &regs->pc, sizeof(unsigned long));
 	err |= __copy_to_user(&sc->regs.sr, &regs->sr, sizeof(unsigned long));
-	err |= __copy_to_user(&sc->fpcsr, &regs->fpcsr, sizeof(unsigned long));
+	err |= save_fp_state(sc);
 
 	return err;
 }

arch/openrisc/kernel/traps.c

@@ -31,6 +31,7 @@
 #include <linux/uaccess.h>
 
 #include <asm/bug.h>
+#include <asm/fpu.h>
 #include <asm/io.h>
 #include <asm/processor.h>
 #include <asm/unwinder.h>
@@ -51,16 +52,16 @@ static void print_trace(void *data, unsigned long addr, int reliable)
 {
 	const char *loglvl = data;
 
-	printk("%s[<%p>] %s%pS\n", loglvl, (void *) addr, reliable ? "" : "? ",
+	pr_info("%s[<%p>] %s%pS\n", loglvl, (void *) addr, reliable ? "" : "? ",
 		(void *) addr);
 }
 
 static void print_data(unsigned long base_addr, unsigned long word, int i)
 {
 	if (i == 0)
-		printk("(%08lx:)\t%08lx", base_addr + (i * 4), word);
+		pr_info("(%08lx:)\t%08lx", base_addr + (i * 4), word);
 	else
-		printk(" %08lx:\t%08lx", base_addr + (i * 4), word);
+		pr_info(" %08lx:\t%08lx", base_addr + (i * 4), word);
 }
 
 /* displays a short stack trace */
@@ -69,7 +70,7 @@ void show_stack(struct task_struct *task, unsigned long *esp, const char *loglvl
 	if (esp == NULL)
 		esp = (unsigned long *)&esp;
 
-	printk("%sCall trace:\n", loglvl);
+	pr_info("%sCall trace:\n", loglvl);
 	unwind_stack((void *)loglvl, esp, print_trace);
 }
 
@@ -83,30 +84,29 @@ void show_registers(struct pt_regs *regs)
 	if (user_mode(regs))
 		in_kernel = 0;
 
-	printk("CPU #: %d\n"
-	       "   PC: %08lx    SR: %08lx    SP: %08lx FPCSR: %08lx\n",
-	       smp_processor_id(), regs->pc, regs->sr, regs->sp,
-	       regs->fpcsr);
-	printk("GPR00: %08lx GPR01: %08lx GPR02: %08lx GPR03: %08lx\n",
+	pr_info("CPU #: %d\n"
+		"   PC: %08lx    SR: %08lx    SP: %08lx\n",
+		smp_processor_id(), regs->pc, regs->sr, regs->sp);
+	pr_info("GPR00: %08lx GPR01: %08lx GPR02: %08lx GPR03: %08lx\n",
 		0L, regs->gpr[1], regs->gpr[2], regs->gpr[3]);
-	printk("GPR04: %08lx GPR05: %08lx GPR06: %08lx GPR07: %08lx\n",
+	pr_info("GPR04: %08lx GPR05: %08lx GPR06: %08lx GPR07: %08lx\n",
 		regs->gpr[4], regs->gpr[5], regs->gpr[6], regs->gpr[7]);
-	printk("GPR08: %08lx GPR09: %08lx GPR10: %08lx GPR11: %08lx\n",
+	pr_info("GPR08: %08lx GPR09: %08lx GPR10: %08lx GPR11: %08lx\n",
 		regs->gpr[8], regs->gpr[9], regs->gpr[10], regs->gpr[11]);
-	printk("GPR12: %08lx GPR13: %08lx GPR14: %08lx GPR15: %08lx\n",
+	pr_info("GPR12: %08lx GPR13: %08lx GPR14: %08lx GPR15: %08lx\n",
 		regs->gpr[12], regs->gpr[13], regs->gpr[14], regs->gpr[15]);
-	printk("GPR16: %08lx GPR17: %08lx GPR18: %08lx GPR19: %08lx\n",
+	pr_info("GPR16: %08lx GPR17: %08lx GPR18: %08lx GPR19: %08lx\n",
 		regs->gpr[16], regs->gpr[17], regs->gpr[18], regs->gpr[19]);
-	printk("GPR20: %08lx GPR21: %08lx GPR22: %08lx GPR23: %08lx\n",
+	pr_info("GPR20: %08lx GPR21: %08lx GPR22: %08lx GPR23: %08lx\n",
 		regs->gpr[20], regs->gpr[21], regs->gpr[22], regs->gpr[23]);
-	printk("GPR24: %08lx GPR25: %08lx GPR26: %08lx GPR27: %08lx\n",
+	pr_info("GPR24: %08lx GPR25: %08lx GPR26: %08lx GPR27: %08lx\n",
 		regs->gpr[24], regs->gpr[25], regs->gpr[26], regs->gpr[27]);
-	printk("GPR28: %08lx GPR29: %08lx GPR30: %08lx GPR31: %08lx\n",
+	pr_info("GPR28: %08lx GPR29: %08lx GPR30: %08lx GPR31: %08lx\n",
 		regs->gpr[28], regs->gpr[29], regs->gpr[30], regs->gpr[31]);
-	printk("  RES: %08lx oGPR11: %08lx\n",
+	pr_info("  RES: %08lx oGPR11: %08lx\n",
 		regs->gpr[11], regs->orig_gpr11);
 
-	printk("Process %s (pid: %d, stackpage=%08lx)\n",
+	pr_info("Process %s (pid: %d, stackpage=%08lx)\n",
 		current->comm, current->pid, (unsigned long)current);
 	/*
 	 * When in-kernel, we also print out the stack and code at the
@@ -114,26 +114,26 @@ void show_registers(struct pt_regs *regs)
 	 */
 	if (in_kernel) {
 
-		printk("\nStack: ");
+		pr_info("\nStack: ");
 		show_stack(NULL, (unsigned long *)esp, KERN_EMERG);
 
 		if (esp < PAGE_OFFSET)
 			goto bad_stack;
 
-		printk("\n");
+		pr_info("\n");
 		for (i = -8; i < 24; i += 1) {
 			unsigned long word;
 
 			if (__get_user(word, &((unsigned long *)esp)[i])) {
 bad_stack:
-				printk(" Bad Stack value.");
+				pr_info(" Bad Stack value.");
 				break;
 			}
 
 			print_data(esp, word, i);
 		}
 
-		printk("\nCode: ");
+		pr_info("\nCode: ");
 		if (regs->pc < PAGE_OFFSET)
 			goto bad;
 
@@ -142,14 +142,14 @@ void show_registers(struct pt_regs *regs)
 
 			if (__get_user(word, &((unsigned long *)regs->pc)[i])) {
 bad:
-				printk(" Bad PC value.");
+				pr_info(" Bad PC value.");
 				break;
 			}
 
 			print_data(regs->pc, word, i);
 		}
 	}
-	printk("\n");
+	pr_info("\n");
 }
 
 /* This is normally the 'Oops' routine */
@@ -157,10 +157,10 @@ void __noreturn die(const char *str, struct pt_regs *regs, long err)
 {
 
 	console_verbose();
-	printk("\n%s#: %04lx\n", str, err & 0xffff);
+	pr_emerg("\n%s#: %04lx\n", str, err & 0xffff);
 	show_registers(regs);
 #ifdef CONFIG_JUMP_UPON_UNHANDLED_EXCEPTION
-	printk("\n\nUNHANDLED_EXCEPTION: entering infinite loop\n");
+	pr_emerg("\n\nUNHANDLED_EXCEPTION: entering infinite loop\n");
 
 	/* shut down interrupts */
 	local_irq_disable();
@@ -173,15 +173,20 @@ void __noreturn die(const char *str, struct pt_regs *regs, long err)
 
 asmlinkage void unhandled_exception(struct pt_regs *regs, int ea, int vector)
 {
-	printk("Unable to handle exception at EA =0x%x, vector 0x%x",
+	pr_emerg("Unable to handle exception at EA =0x%x, vector 0x%x",
 		 ea, vector);
 	die("Oops", regs, 9);
 }
 
 asmlinkage void do_fpe_trap(struct pt_regs *regs, unsigned long address)
 {
+	if (user_mode(regs)) {
 		int code = FPE_FLTUNK;
-	unsigned long fpcsr = regs->fpcsr;
+#ifdef CONFIG_FPU
+		unsigned long fpcsr;
+
+		save_fpu(current);
+		fpcsr = current->thread.fpcsr;
 
 		if (fpcsr & SPR_FPCSR_IVF)
 			code = FPE_FLTINV;
@@ -195,14 +200,24 @@ asmlinkage void do_fpe_trap(struct pt_regs *regs, unsigned long address)
 			code = FPE_FLTRES;
 
 		/* Clear all flags */
-	regs->fpcsr &= ~SPR_FPCSR_ALLF;
-
+		current->thread.fpcsr &= ~SPR_FPCSR_ALLF;
+		restore_fpu(current);
+#endif
 		force_sig_fault(SIGFPE, code, (void __user *)regs->pc);
+	} else {
+		pr_emerg("KERNEL: Illegal fpe exception 0x%.8lx\n", regs->pc);
+		die("Die:", regs, SIGFPE);
+	}
 }
 
 asmlinkage void do_trap(struct pt_regs *regs, unsigned long address)
 {
+	if (user_mode(regs)) {
 		force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->pc);
+	} else {
+		pr_emerg("KERNEL: Illegal trap exception 0x%.8lx\n", regs->pc);
+		die("Die:", regs, SIGILL);
+	}
 }
 
 asmlinkage void do_unaligned_access(struct pt_regs *regs, unsigned long address)
@@ -211,8 +226,7 @@ asmlinkage void do_unaligned_access(struct pt_regs *regs, unsigned long address)
 		/* Send a SIGBUS */
 		force_sig_fault(SIGBUS, BUS_ADRALN, (void __user *)address);
 	} else {
-		printk("KERNEL: Unaligned Access 0x%.8lx\n", address);
-		show_registers(regs);
+		pr_emerg("KERNEL: Unaligned Access 0x%.8lx\n", address);
 		die("Die:", regs, address);
 	}
 
@@ -224,8 +238,7 @@ asmlinkage void do_bus_fault(struct pt_regs *regs, unsigned long address)
 		/* Send a SIGBUS */
 		force_sig_fault(SIGBUS, BUS_ADRERR, (void __user *)address);
 	} else {		/* Kernel mode */
-		printk("KERNEL: Bus error (SIGBUS) 0x%.8lx\n", address);
-		show_registers(regs);
+		pr_emerg("KERNEL: Bus error (SIGBUS) 0x%.8lx\n", address);
 		die("Die:", regs, address);
 	}
 }
@@ -419,9 +432,8 @@ asmlinkage void do_illegal_instruction(struct pt_regs *regs,
 		/* Send a SIGILL */
 		force_sig_fault(SIGILL, ILL_ILLOPC, (void __user *)address);
 	} else {		/* Kernel mode */
-		printk("KERNEL: Illegal instruction (SIGILL) 0x%.8lx\n",
+		pr_emerg("KERNEL: Illegal instruction (SIGILL) 0x%.8lx\n",
 			 address);
-		show_registers(regs);
 		die("Die:", regs, address);
 	}
 }