Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus

Pull MIPS updates from Ralf Baechle:
 "MIPS updates:

   - All the things that didn't make 3.10.
   - Removes the Windriver PPMC platform.  Nobody will miss it.
   - Remove a workaround from kernel/irq/irqdomain.c which was there
     exclusivly for MIPS.  Patch by Grant Likely.
   - More small improvments for the SEAD 3 platform
   - Improvments on the BMIPS / SMP support for the BCM63xx series.
   - Various cleanups of dead leftovers.
   - Platform support for the Cavium Octeon-based EdgeRouter Lite.

  Two large KVM patchsets didn't make it for this pull request because
  their respective authors are vacationing"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (124 commits)
  MIPS: Kconfig: Add missing MODULES dependency to VPE_LOADER
  MIPS: BCM63xx: CLK: Add dummy clk_{set,round}_rate() functions
  MIPS: SEAD3: Disable L2 cache on SEAD-3.
  MIPS: BCM63xx: Enable second core SMP on BCM6328 if available
  MIPS: BCM63xx: Add SMP support to prom.c
  MIPS: define write{b,w,l,q}_relaxed
  MIPS: Expose missing pci_io{map,unmap} declarations
  MIPS: Malta: Update GCMP detection.
  Revert "MIPS: make CAC_ADDR and UNCAC_ADDR account for PHYS_OFFSET"
  MIPS: APSP: Remove <asm/kspd.h>
  SSB: Kconfig: Amend SSB_EMBEDDED dependencies
  MIPS: microMIPS: Fix improper definition of ISA exception bit.
  MIPS: Don't try to decode microMIPS branch instructions where they cannot exist.
  MIPS: Declare emulate_load_store_microMIPS as a static function.
  MIPS: Fix typos and cleanup comment
  MIPS: Cleanup indentation and whitespace
  MIPS: BMIPS: support booting from physical CPU other than 0
  MIPS: Only set cpu_has_mmips if SYS_SUPPORTS_MICROMIPS
  MIPS: GIC: Fix gic_set_affinity infinite loop
  MIPS: Don't save/restore OCTEON wide multiplier state on syscalls.
  ...

arch/mips/kernel/asm-offsets.c

@@ -82,6 +82,9 @@ void output_task_defines(void)
 	OFFSET(TASK_FLAGS, task_struct, flags);
 	OFFSET(TASK_MM, task_struct, mm);
 	OFFSET(TASK_PID, task_struct, pid);
+#if defined(CONFIG_CC_STACKPROTECTOR)
+	OFFSET(TASK_STACK_CANARY, task_struct, stack_canary);
+#endif
 	DEFINE(TASK_STRUCT_SIZE, sizeof(struct task_struct));
 	BLANK();
 }

arch/mips/kernel/branch.c

@@ -467,5 +467,4 @@ unaligned:
 	printk("%s: unaligned epc - sending SIGBUS.\n", current->comm);
 	force_sig(SIGBUS, current);
 	return -EFAULT;
-
 }

arch/mips/kernel/cpu-bugs64.c

@@ -6,6 +6,7 @@
  * as published by the Free Software Foundation; either version
  * 2 of the License, or (at your option) any later version.
  */
+#include <linux/context_tracking.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/ptrace.h>
@@ -171,8 +172,12 @@ static volatile int daddi_ov __cpuinitdata;
 
 asmlinkage void __init do_daddi_ov(struct pt_regs *regs)
 {
+	enum ctx_state prev_state;
+
+	prev_state = exception_enter();
 	daddi_ov = 1;
 	regs->cp0_epc += 4;
+	exception_exit(prev_state);
 }
 
 static inline void check_daddi(void)

arch/mips/kernel/cpu-probe.c

@@ -146,8 +146,7 @@ static void __cpuinit set_isa(struct cpuinfo_mips *c, unsigned int isa)
 	case MIPS_CPU_ISA_IV:
 		c->isa_level |= MIPS_CPU_ISA_IV;
 	case MIPS_CPU_ISA_III:
-		c->isa_level |= MIPS_CPU_ISA_I | MIPS_CPU_ISA_II |
-				MIPS_CPU_ISA_III;
+		c->isa_level |= MIPS_CPU_ISA_II | MIPS_CPU_ISA_III;
 		break;
 
 	case MIPS_CPU_ISA_M32R2:
@@ -156,8 +155,6 @@ static void __cpuinit set_isa(struct cpuinfo_mips *c, unsigned int isa)
 		c->isa_level |= MIPS_CPU_ISA_M32R1;
 	case MIPS_CPU_ISA_II:
 		c->isa_level |= MIPS_CPU_ISA_II;
-	case MIPS_CPU_ISA_I:
-		c->isa_level |= MIPS_CPU_ISA_I;
 		break;
 	}
 }
@@ -272,9 +269,6 @@ static inline unsigned int decode_config3(struct cpuinfo_mips *c)
 		c->options |= MIPS_CPU_ULRI;
 	if (config3 & MIPS_CONF3_ISA)
 		c->options |= MIPS_CPU_MICROMIPS;
-#ifdef CONFIG_CPU_MICROMIPS
-	write_c0_config3(read_c0_config3() | MIPS_CONF3_ISA_OE);
-#endif
 	if (config3 & MIPS_CONF3_VZ)
 		c->ases |= MIPS_ASE_VZ;
 
@@ -332,7 +326,6 @@ static inline void cpu_probe_legacy(struct cpuinfo_mips *c, unsigned int cpu)
 	case PRID_IMP_R2000:
 		c->cputype = CPU_R2000;
 		__cpu_name[cpu] = "R2000";
-		set_isa(c, MIPS_CPU_ISA_I);
 		c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
 			     MIPS_CPU_NOFPUEX;
 		if (__cpu_has_fpu())
@@ -352,7 +345,6 @@ static inline void cpu_probe_legacy(struct cpuinfo_mips *c, unsigned int cpu)
 			c->cputype = CPU_R3000;
 			__cpu_name[cpu] = "R3000";
 		}
-		set_isa(c, MIPS_CPU_ISA_I);
 		c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
 			     MIPS_CPU_NOFPUEX;
 		if (__cpu_has_fpu())
@@ -455,7 +447,6 @@ static inline void cpu_probe_legacy(struct cpuinfo_mips *c, unsigned int cpu)
 		break;
 	#endif
 	case PRID_IMP_TX39:
-		set_isa(c, MIPS_CPU_ISA_I);
 		c->options = MIPS_CPU_TLB | MIPS_CPU_TX39_CACHE;
 
 		if ((c->processor_id & 0xf0) == (PRID_REV_TX3927 & 0xf0)) {
@@ -959,6 +950,7 @@ static inline void cpu_probe_netlogic(struct cpuinfo_mips *c, int cpu)
 		set_isa(c, MIPS_CPU_ISA_M64R1);
 		c->tlbsize = ((read_c0_config1() >> 25) & 0x3f) + 1;
 	}
+	c->kscratch_mask = 0xf;
 }
 
 #ifdef CONFIG_64BIT

arch/mips/kernel/head.S

@@ -27,45 +27,6 @@
 
 #include <kernel-entry-init.h>
 
-	/*
-	 * inputs are the text nasid in t1, data nasid in t2.
-	 */
-	.macro MAPPED_KERNEL_SETUP_TLB
-#ifdef CONFIG_MAPPED_KERNEL
-	/*
-	 * This needs to read the nasid - assume 0 for now.
-	 * Drop in 0xffffffffc0000000 in tlbhi, 0+VG in tlblo_0,
-	 * 0+DVG in tlblo_1.
-	 */
-	dli	t0, 0xffffffffc0000000
-	dmtc0	t0, CP0_ENTRYHI
-	li	t0, 0x1c000		# Offset of text into node memory
-	dsll	t1, NASID_SHFT		# Shift text nasid into place
-	dsll	t2, NASID_SHFT		# Same for data nasid
-	or	t1, t1, t0		# Physical load address of kernel text
-	or	t2, t2, t0		# Physical load address of kernel data
-	dsrl	t1, 12			# 4K pfn
-	dsrl	t2, 12			# 4K pfn
-	dsll	t1, 6			# Get pfn into place
-	dsll	t2, 6			# Get pfn into place
-	li	t0, ((_PAGE_GLOBAL|_PAGE_VALID| _CACHE_CACHABLE_COW) >> 6)
-	or	t0, t0, t1
-	mtc0	t0, CP0_ENTRYLO0	# physaddr, VG, cach exlwr
-	li	t0, ((_PAGE_GLOBAL|_PAGE_VALID| _PAGE_DIRTY|_CACHE_CACHABLE_COW) >> 6)
-	or	t0, t0, t2
-	mtc0	t0, CP0_ENTRYLO1	# physaddr, DVG, cach exlwr
-	li	t0, 0x1ffe000		# MAPPED_KERN_TLBMASK, TLBPGMASK_16M
-	mtc0	t0, CP0_PAGEMASK
-	li	t0, 0			# KMAP_INX
-	mtc0	t0, CP0_INDEX
-	li	t0, 1
-	mtc0	t0, CP0_WIRED
-	tlbwi
-#else
-	mtc0	zero, CP0_WIRED
-#endif
-	.endm
-
 	/*
 	 * For the moment disable interrupts, mark the kernel mode and
 	 * set ST0_KX so that the CPU does not spit fire when using

arch/mips/kernel/irq-gic.c

@@ -219,16 +219,15 @@ static int gic_set_affinity(struct irq_data *d, const struct cpumask *cpumask,
 
 	/* Assumption : cpumask refers to a single CPU */
 	spin_lock_irqsave(&gic_lock, flags);
-	for (;;) {
-		/* Re-route this IRQ */
-		GIC_SH_MAP_TO_VPE_SMASK(irq, first_cpu(tmp));
 
-		/* Update the pcpu_masks */
-		for (i = 0; i < NR_CPUS; i++)
-			clear_bit(irq, pcpu_masks[i].pcpu_mask);
-		set_bit(irq, pcpu_masks[first_cpu(tmp)].pcpu_mask);
+	/* Re-route this IRQ */
+	GIC_SH_MAP_TO_VPE_SMASK(irq, first_cpu(tmp));
+
+	/* Update the pcpu_masks */
+	for (i = 0; i < NR_CPUS; i++)
+		clear_bit(irq, pcpu_masks[i].pcpu_mask);
+	set_bit(irq, pcpu_masks[first_cpu(tmp)].pcpu_mask);
 
-	}
 	cpumask_copy(d->affinity, cpumask);
 	spin_unlock_irqrestore(&gic_lock, flags);
 

arch/mips/kernel/mcount.S

@@ -168,14 +168,10 @@ NESTED(ftrace_graph_caller, PT_SIZE, ra)
 #endif
 
 	/* arg3: Get frame pointer of current stack */
-#ifdef CONFIG_FRAME_POINTER
-	move	a2, fp
-#else /* ! CONFIG_FRAME_POINTER */
 #ifdef CONFIG_64BIT
 	PTR_LA	a2, PT_SIZE(sp)
 #else
 	PTR_LA	a2, (PT_SIZE+8)(sp)
-#endif
 #endif
 
 	jal	prepare_ftrace_return

arch/mips/kernel/octeon_switch.S

@@ -40,33 +40,6 @@
 	cpu_save_nonscratch a0
 	LONG_S	ra, THREAD_REG31(a0)
 
-	/* check if we need to save COP2 registers */
-	PTR_L	t2, TASK_THREAD_INFO(a0)
-	LONG_L	t0, ST_OFF(t2)
-	bbit0	t0, 30, 1f
-
-	/* Disable COP2 in the stored process state */
-	li	t1, ST0_CU2
-	xor	t0, t1
-	LONG_S	t0, ST_OFF(t2)
-
-	/* Enable COP2 so we can save it */
-	mfc0	t0, CP0_STATUS
-	or	t0, t1
-	mtc0	t0, CP0_STATUS
-
-	/* Save COP2 */
-	daddu	a0, THREAD_CP2
-	jal octeon_cop2_save
-	dsubu	a0, THREAD_CP2
-
-	/* Disable COP2 now that we are done */
-	mfc0	t0, CP0_STATUS
-	li	t1, ST0_CU2
-	xor	t0, t1
-	mtc0	t0, CP0_STATUS
-
-1:
 #if CONFIG_CAVIUM_OCTEON_CVMSEG_SIZE > 0
 	/* Check if we need to store CVMSEG state */
 	mfc0	t0, $11,7	/* CvmMemCtl */
@@ -98,6 +71,13 @@
 	mtc0	t0, $11,7	/* CvmMemCtl */
 #endif
 3:
+
+#if defined(CONFIG_CC_STACKPROTECTOR) && !defined(CONFIG_SMP)
+	PTR_L	t8, __stack_chk_guard
+	LONG_L	t9, TASK_STACK_CANARY(a1)
+	LONG_S	t9, 0(t8)
+#endif
+
 	/*
 	 * The order of restoring the registers takes care of the race
 	 * updating $28, $29 and kernelsp without disabling ints.

arch/mips/kernel/proc.c

@@ -66,9 +66,7 @@ static int show_cpuinfo(struct seq_file *m, void *v)
 		seq_printf(m, "]\n");
 	}
 	if (cpu_has_mips_r) {
-		seq_printf(m, "isa\t\t\t:");
-		if (cpu_has_mips_1)
-			seq_printf(m, "%s", " mips1");
+		seq_printf(m, "isa\t\t\t: mips1");
 		if (cpu_has_mips_2)
 			seq_printf(m, "%s", " mips2");
 		if (cpu_has_mips_3)

arch/mips/kernel/process.c

@@ -201,9 +201,12 @@ int dump_task_fpu(struct task_struct *t, elf_fpregset_t *fpr)
 	return 1;
 }
 
-/*
- *
- */
+#ifdef CONFIG_CC_STACKPROTECTOR
+#include <linux/stackprotector.h>
+unsigned long __stack_chk_guard __read_mostly;
+EXPORT_SYMBOL(__stack_chk_guard);
+#endif
+
 struct mips_frame_info {
 	void		*func;
 	unsigned long	func_size;

arch/mips/kernel/prom.c

@@ -30,7 +30,7 @@ __init void mips_set_machine_name(const char *name)
 	if (name == NULL)
 		return;
 
-	strncpy(mips_machine_name, name, sizeof(mips_machine_name));
+	strlcpy(mips_machine_name, name, sizeof(mips_machine_name));
 	pr_info("MIPS: machine is %s\n", mips_get_machine_name());
 }
 

arch/mips/kernel/ptrace.c

@@ -15,6 +15,7 @@
  * binaries.
  */
 #include <linux/compiler.h>
+#include <linux/context_tracking.h>
 #include <linux/kernel.h>
 #include <linux/sched.h>
 #include <linux/mm.h>
@@ -534,6 +535,8 @@ static inline int audit_arch(void)
  */
 asmlinkage void syscall_trace_enter(struct pt_regs *regs)
 {
+	user_exit();
+
 	/* do the secure computing check first */
 	secure_computing_strict(regs->regs[2]);
 
@@ -570,6 +573,13 @@ out:
  */
 asmlinkage void syscall_trace_leave(struct pt_regs *regs)
 {
+        /*
+	 * We may come here right after calling schedule_user()
+	 * or do_notify_resume(), in which case we can be in RCU
+	 * user mode.
+	 */
+	user_exit();
+
 	audit_syscall_exit(regs);
 
 	if (!(current->ptrace & PT_PTRACED))
@@ -592,4 +602,6 @@ asmlinkage void syscall_trace_leave(struct pt_regs *regs)
 		send_sig(current->exit_code, current, 1);
 		current->exit_code = 0;
 	}
+
+	user_enter();
 }

arch/mips/kernel/r2300_switch.S

@@ -65,6 +65,13 @@ LEAF(resume)
 	fpu_save_single a0, t0			# clobbers t0
 
 1:
+
+#if defined(CONFIG_CC_STACKPROTECTOR) && !defined(CONFIG_SMP)
+	PTR_L	t8, __stack_chk_guard
+	LONG_L	t9, TASK_STACK_CANARY(a1)
+	LONG_S	t9, 0(t8)
+#endif
+
 	/*
 	 * The order of restoring the registers takes care of the race
 	 * updating $28, $29 and kernelsp without disabling ints.

arch/mips/kernel/r4k_switch.S

@@ -68,6 +68,12 @@
 						# clobbers t1
 1:
 
+#if defined(CONFIG_CC_STACKPROTECTOR) && !defined(CONFIG_SMP)
+	PTR_L	t8, __stack_chk_guard
+	LONG_L	t9, TASK_STACK_CANARY(a1)
+	LONG_S	t9, 0(t8)
+#endif
+
 	/*
 	 * The order of restoring the registers takes care of the race
 	 * updating $28, $29 and kernelsp without disabling ints.

arch/mips/kernel/rtlx.c

@@ -437,7 +437,6 @@ static ssize_t file_write(struct file *file, const char __user * buffer,
 			  size_t count, loff_t * ppos)
 {
 	int minor = iminor(file_inode(file));
-	struct rtlx_channel *rt = &rtlx->channel[minor];
 
 	/* any space left... */
 	if (!rtlx_write_poll(minor)) {

arch/mips/kernel/scall32-o32.S

@@ -52,7 +52,7 @@ NESTED(handle_sys, PT_SIZE, sp)
 
 stack_done:
 	lw	t0, TI_FLAGS($28)	# syscall tracing enabled?
-	li	t1, _TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT
+	li	t1, _TIF_WORK_SYSCALL_ENTRY
 	and	t0, t1
 	bnez	t0, syscall_trace_entry # -> yes
 

arch/mips/kernel/scall64-64.S

@@ -54,7 +54,7 @@ NESTED(handle_sys64, PT_SIZE, sp)
 
 	sd	a3, PT_R26(sp)		# save a3 for syscall restarting
 
-	li	t1, _TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT
+	li	t1, _TIF_WORK_SYSCALL_ENTRY
 	LONG_L	t0, TI_FLAGS($28)	# syscall tracing enabled?
 	and	t0, t1, t0
 	bnez	t0, syscall_trace_entry

arch/mips/kernel/scall64-n32.S

@@ -47,7 +47,7 @@ NESTED(handle_sysn32, PT_SIZE, sp)
 
 	sd	a3, PT_R26(sp)		# save a3 for syscall restarting
 
-	li	t1, _TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT
+	li	t1, _TIF_WORK_SYSCALL_ENTRY
 	LONG_L	t0, TI_FLAGS($28)	# syscall tracing enabled?
 	and	t0, t1, t0
 	bnez	t0, n32_syscall_trace_entry

arch/mips/kernel/scall64-o32.S

@@ -81,7 +81,7 @@ NESTED(handle_sys, PT_SIZE, sp)
 	PTR	4b, bad_stack
 	.previous
 
-	li	t1, _TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT
+	li	t1, _TIF_WORK_SYSCALL_ENTRY
 	LONG_L	t0, TI_FLAGS($28)	# syscall tracing enabled?
 	and	t0, t1, t0
 	bnez	t0, trace_a_syscall

arch/mips/kernel/signal.c

@@ -8,6 +8,7 @@
  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
  */
 #include <linux/cache.h>
+#include <linux/context_tracking.h>
 #include <linux/irqflags.h>
 #include <linux/sched.h>
 #include <linux/mm.h>
@@ -573,6 +574,8 @@ asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused,
 {
 	local_irq_enable();
 
+	user_exit();
+
 	/* deal with pending signal delivery */
 	if (thread_info_flags & _TIF_SIGPENDING)
 		do_signal(regs);
@@ -581,6 +584,8 @@ asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused,
 		clear_thread_flag(TIF_NOTIFY_RESUME);
 		tracehook_notify_resume(regs);
 	}
+
+	user_enter();
 }
 
 #ifdef CONFIG_SMP

arch/mips/kernel/smp-bmips.c

@@ -63,7 +63,7 @@ static irqreturn_t bmips_ipi_interrupt(int irq, void *dev_id);
 
 static void __init bmips_smp_setup(void)
 {
-	int i;
+	int i, cpu = 1, boot_cpu = 0;
 
 #if defined(CONFIG_CPU_BMIPS4350) || defined(CONFIG_CPU_BMIPS4380)
 	/* arbitration priority */
@@ -72,13 +72,22 @@ static void __init bmips_smp_setup(void)
 	/* NBK and weak order flags */
 	set_c0_brcm_config_0(0x30000);
 
+	/* Find out if we are running on TP0 or TP1 */
+	boot_cpu = !!(read_c0_brcm_cmt_local() & (1 << 31));
+
 	/*
 	 * MIPS interrupts 0,1 (SW INT 0,1) cross over to the other thread
 	 * MIPS interrupt 2 (HW INT 0) is the CPU0 L1 controller output
 	 * MIPS interrupt 3 (HW INT 1) is the CPU1 L1 controller output
+	 *
+	 * If booting from TP1, leave the existing CMT interrupt routing
+	 * such that TP0 responds to SW1 and TP1 responds to SW0.
 	 */
-	change_c0_brcm_cmt_intr(0xf8018000,
-		(0x02 << 27) | (0x03 << 15));
+	if (boot_cpu == 0)
+		change_c0_brcm_cmt_intr(0xf8018000,
+					(0x02 << 27) | (0x03 << 15));
+	else
+		change_c0_brcm_cmt_intr(0xf8018000, (0x1d << 27));
 
 	/* single core, 2 threads (2 pipelines) */
 	max_cpus = 2;
@@ -106,9 +115,15 @@ static void __init bmips_smp_setup(void)
 	if (!board_ebase_setup)
 		board_ebase_setup = &bmips_ebase_setup;
 
+	__cpu_number_map[boot_cpu] = 0;
+	__cpu_logical_map[0] = boot_cpu;
+
 	for (i = 0; i < max_cpus; i++) {
-		__cpu_number_map[i] = 1;
-		__cpu_logical_map[i] = 1;
+		if (i != boot_cpu) {
+			__cpu_number_map[i] = cpu;
+			__cpu_logical_map[cpu] = i;
+			cpu++;
+		}
 		set_cpu_possible(i, 1);
 		set_cpu_present(i, 1);
 	}
@@ -157,7 +172,9 @@ static void bmips_boot_secondary(int cpu, struct task_struct *idle)
 		bmips_send_ipi_single(cpu, 0);
 	else {
 #if defined(CONFIG_CPU_BMIPS4350) || defined(CONFIG_CPU_BMIPS4380)
-		set_c0_brcm_cmt_ctrl(0x01);
+		/* Reset slave TP1 if booting from TP0 */
+		if (cpu_logical_map(cpu) == 0)
+			set_c0_brcm_cmt_ctrl(0x01);
 #elif defined(CONFIG_CPU_BMIPS5000)
 		if (cpu & 0x01)
 			write_c0_brcm_action(ACTION_BOOT_THREAD(cpu));

arch/mips/kernel/traps.c

@@ -13,6 +13,7 @@
  */
 #include <linux/bug.h>
 #include <linux/compiler.h>
+#include <linux/context_tracking.h>
 #include <linux/kexec.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
@@ -264,7 +265,7 @@ static void __show_regs(const struct pt_regs *regs)
 
 	printk("Status: %08x	", (uint32_t) regs->cp0_status);
 
-	if (current_cpu_data.isa_level == MIPS_CPU_ISA_I) {
+	if (cpu_has_3kex) {
 		if (regs->cp0_status & ST0_KUO)
 			printk("KUo ");
 		if (regs->cp0_status & ST0_IEO)
@@ -277,7 +278,7 @@ static void __show_regs(const struct pt_regs *regs)
 			printk("KUc ");
 		if (regs->cp0_status & ST0_IEC)
 			printk("IEc ");
-	} else {
+	} else if (cpu_has_4kex) {
 		if (regs->cp0_status & ST0_KX)
 			printk("KX ");
 		if (regs->cp0_status & ST0_SX)
@@ -423,7 +424,9 @@ asmlinkage void do_be(struct pt_regs *regs)
 	const struct exception_table_entry *fixup = NULL;
 	int data = regs->cp0_cause & 4;
 	int action = MIPS_BE_FATAL;
+	enum ctx_state prev_state;
 
+	prev_state = exception_enter();
 	/* XXX For now.	 Fixme, this searches the wrong table ...  */
 	if (data && !user_mode(regs))
 		fixup = search_dbe_tables(exception_epc(regs));
@@ -436,11 +439,11 @@ asmlinkage void do_be(struct pt_regs *regs)
 
 	switch (action) {
 	case MIPS_BE_DISCARD:
-		return;
+		goto out;
 	case MIPS_BE_FIXUP:
 		if (fixup) {
 			regs->cp0_epc = fixup->nextinsn;
-			return;
+			goto out;
 		}
 		break;
 	default:
@@ -455,10 +458,13 @@ asmlinkage void do_be(struct pt_regs *regs)
 	       field, regs->cp0_epc, field, regs->regs[31]);
 	if (notify_die(DIE_OOPS, "bus error", regs, 0, regs_to_trapnr(regs), SIGBUS)
 	    == NOTIFY_STOP)
-		return;
+		goto out;
 
 	die_if_kernel("Oops", regs);
 	force_sig(SIGBUS, current);
+
+out:
+	exception_exit(prev_state);
 }
 
 /*
@@ -673,8 +679,10 @@ static int simulate_sync(struct pt_regs *regs, unsigned int opcode)
 
 asmlinkage void do_ov(struct pt_regs *regs)
 {
+	enum ctx_state prev_state;
 	siginfo_t info;
 
+	prev_state = exception_enter();
 	die_if_kernel("Integer overflow", regs);
 
 	info.si_code = FPE_INTOVF;
@@ -682,6 +690,7 @@ asmlinkage void do_ov(struct pt_regs *regs)
 	info.si_errno = 0;
 	info.si_addr = (void __user *) regs->cp0_epc;
 	force_sig_info(SIGFPE, &info, current);
+	exception_exit(prev_state);
 }
 
 int process_fpemu_return(int sig, void __user *fault_addr)
@@ -713,11 +722,13 @@ int process_fpemu_return(int sig, void __user *fault_addr)
  */
 asmlinkage void do_fpe(struct pt_regs *regs, unsigned long fcr31)
 {
+	enum ctx_state prev_state;
 	siginfo_t info = {0};
 
+	prev_state = exception_enter();
 	if (notify_die(DIE_FP, "FP exception", regs, 0, regs_to_trapnr(regs), SIGFPE)
 	    == NOTIFY_STOP)
-		return;
+		goto out;
 	die_if_kernel("FP exception in kernel code", regs);
 
 	if (fcr31 & FPU_CSR_UNI_X) {
@@ -753,7 +764,7 @@ asmlinkage void do_fpe(struct pt_regs *regs, unsigned long fcr31)
 		/* If something went wrong, signal */
 		process_fpemu_return(sig, fault_addr);
 
-		return;
+		goto out;
 	} else if (fcr31 & FPU_CSR_INV_X)
 		info.si_code = FPE_FLTINV;
 	else if (fcr31 & FPU_CSR_DIV_X)
@@ -770,6 +781,9 @@ asmlinkage void do_fpe(struct pt_regs *regs, unsigned long fcr31)
 	info.si_errno = 0;
 	info.si_addr = (void __user *) regs->cp0_epc;
 	force_sig_info(SIGFPE, &info, current);
+
+out:
+	exception_exit(prev_state);
 }
 
 static void do_trap_or_bp(struct pt_regs *regs, unsigned int code,
@@ -835,9 +849,11 @@ static void do_trap_or_bp(struct pt_regs *regs, unsigned int code,
 asmlinkage void do_bp(struct pt_regs *regs)
 {
 	unsigned int opcode, bcode;
+	enum ctx_state prev_state;
 	unsigned long epc;
 	u16 instr[2];
 
+	prev_state = exception_enter();
 	if (get_isa16_mode(regs->cp0_epc)) {
 		/* Calculate EPC. */
 		epc = exception_epc(regs);
@@ -852,7 +868,7 @@ asmlinkage void do_bp(struct pt_regs *regs)
 				goto out_sigsegv;
 		    bcode = (instr[0] >> 6) & 0x3f;
 		    do_trap_or_bp(regs, bcode, "Break");
-		    return;
+		    goto out;
 		}
 	} else {
 		if (__get_user(opcode, (unsigned int __user *) exception_epc(regs)))
@@ -876,12 +892,12 @@ asmlinkage void do_bp(struct pt_regs *regs)
 	switch (bcode) {
 	case BRK_KPROBE_BP:
 		if (notify_die(DIE_BREAK, "debug", regs, bcode, regs_to_trapnr(regs), SIGTRAP) == NOTIFY_STOP)
-			return;
+			goto out;
 		else
 			break;
 	case BRK_KPROBE_SSTEPBP:
 		if (notify_die(DIE_SSTEPBP, "single_step", regs, bcode, regs_to_trapnr(regs), SIGTRAP) == NOTIFY_STOP)
-			return;
+			goto out;
 		else
 			break;
 	default:
@@ -889,18 +905,24 @@ asmlinkage void do_bp(struct pt_regs *regs)
 	}
 
 	do_trap_or_bp(regs, bcode, "Break");
+
+out:
+	exception_exit(prev_state);
 	return;
 
 out_sigsegv:
 	force_sig(SIGSEGV, current);
+	goto out;
 }
 
 asmlinkage void do_tr(struct pt_regs *regs)
 {
 	u32 opcode, tcode = 0;
+	enum ctx_state prev_state;
 	u16 instr[2];
 	unsigned long epc = msk_isa16_mode(exception_epc(regs));
 
+	prev_state = exception_enter();
 	if (get_isa16_mode(regs->cp0_epc)) {
 		if (__get_user(instr[0], (u16 __user *)(epc + 0)) ||
 		    __get_user(instr[1], (u16 __user *)(epc + 2)))
@@ -918,10 +940,14 @@ asmlinkage void do_tr(struct pt_regs *regs)
 	}
 
 	do_trap_or_bp(regs, tcode, "Trap");
+
+out:
+	exception_exit(prev_state);
 	return;
 
 out_sigsegv:
 	force_sig(SIGSEGV, current);
+	goto out;
 }
 
 asmlinkage void do_ri(struct pt_regs *regs)
@@ -929,17 +955,19 @@ asmlinkage void do_ri(struct pt_regs *regs)
 	unsigned int __user *epc = (unsigned int __user *)exception_epc(regs);
 	unsigned long old_epc = regs->cp0_epc;
 	unsigned long old31 = regs->regs[31];
+	enum ctx_state prev_state;
 	unsigned int opcode = 0;
 	int status = -1;
 
+	prev_state = exception_enter();
 	if (notify_die(DIE_RI, "RI Fault", regs, 0, regs_to_trapnr(regs), SIGILL)
 	    == NOTIFY_STOP)
-		return;
+		goto out;
 
 	die_if_kernel("Reserved instruction in kernel code", regs);
 
 	if (unlikely(compute_return_epc(regs) < 0))
-		return;
+		goto out;
 
 	if (get_isa16_mode(regs->cp0_epc)) {
 		unsigned short mmop[2] = { 0 };
@@ -974,6 +1002,9 @@ asmlinkage void do_ri(struct pt_regs *regs)
 		regs->regs[31] = old31;
 		force_sig(status, current);
 	}
+
+out:
+	exception_exit(prev_state);
 }
 
 /*
@@ -1025,21 +1056,16 @@ static int default_cu2_call(struct notifier_block *nfb, unsigned long action,
 {
 	struct pt_regs *regs = data;
 
-	switch (action) {
-	default:
-		die_if_kernel("Unhandled kernel unaligned access or invalid "
+	die_if_kernel("COP2: Unhandled kernel unaligned access or invalid "
 			      "instruction", regs);
-		/* Fall through	 */
-
-	case CU2_EXCEPTION:
-		force_sig(SIGILL, current);
-	}
+	force_sig(SIGILL, current);
 
 	return NOTIFY_OK;
 }
 
 asmlinkage void do_cpu(struct pt_regs *regs)
 {
+	enum ctx_state prev_state;
 	unsigned int __user *epc;
 	unsigned long old_epc, old31;
 	unsigned int opcode;
@@ -1047,10 +1073,12 @@ asmlinkage void do_cpu(struct pt_regs *regs)
 	int status;
 	unsigned long __maybe_unused flags;
 
-	die_if_kernel("do_cpu invoked from kernel context!", regs);
-
+	prev_state = exception_enter();
 	cpid = (regs->cp0_cause >> CAUSEB_CE) & 3;
 
+	if (cpid != 2)
+		die_if_kernel("do_cpu invoked from kernel context!", regs);
+
 	switch (cpid) {
 	case 0:
 		epc = (unsigned int __user *)exception_epc(regs);
@@ -1060,7 +1088,7 @@ asmlinkage void do_cpu(struct pt_regs *regs)
 		status = -1;
 
 		if (unlikely(compute_return_epc(regs) < 0))
-			return;
+			goto out;
 
 		if (get_isa16_mode(regs->cp0_epc)) {
 			unsigned short mmop[2] = { 0 };
@@ -1093,7 +1121,7 @@ asmlinkage void do_cpu(struct pt_regs *regs)
 			force_sig(status, current);
 		}
 
-		return;
+		goto out;
 
 	case 3:
 		/*
@@ -1131,19 +1159,26 @@ asmlinkage void do_cpu(struct pt_regs *regs)
 				mt_ase_fp_affinity();
 		}
 
-		return;
+		goto out;
 
 	case 2:
 		raw_notifier_call_chain(&cu2_chain, CU2_EXCEPTION, regs);
-		return;
+		goto out;
 	}
 
 	force_sig(SIGILL, current);
+
+out:
+	exception_exit(prev_state);
 }
 
 asmlinkage void do_mdmx(struct pt_regs *regs)
 {
+	enum ctx_state prev_state;
+
+	prev_state = exception_enter();
 	force_sig(SIGILL, current);
+	exception_exit(prev_state);
 }
 
 /*
@@ -1151,8 +1186,10 @@ asmlinkage void do_mdmx(struct pt_regs *regs)
  */
 asmlinkage void do_watch(struct pt_regs *regs)
 {
+	enum ctx_state prev_state;
 	u32 cause;
 
+	prev_state = exception_enter();
 	/*
 	 * Clear WP (bit 22) bit of cause register so we don't loop
 	 * forever.
@@ -1174,13 +1211,16 @@ asmlinkage void do_watch(struct pt_regs *regs)
 		mips_clear_watch_registers();
 		local_irq_enable();
 	}
+	exception_exit(prev_state);
 }
 
 asmlinkage void do_mcheck(struct pt_regs *regs)
 {
 	const int field = 2 * sizeof(unsigned long);
 	int multi_match = regs->cp0_status & ST0_TS;
+	enum ctx_state prev_state;
 
+	prev_state = exception_enter();
 	show_regs(regs);
 
 	if (multi_match) {
@@ -1202,6 +1242,7 @@ asmlinkage void do_mcheck(struct pt_regs *regs)
 	panic("Caught Machine Check exception - %scaused by multiple "
 	      "matching entries in the TLB.",
 	      (multi_match) ? "" : "not ");
+	exception_exit(prev_state);
 }
 
 asmlinkage void do_mt(struct pt_regs *regs)
@@ -1627,7 +1668,6 @@ void *set_vi_handler(int n, vi_handler_t addr)
 }
 
 extern void tlb_init(void);
-extern void flush_tlb_handlers(void);
 
 /*
  * Timer interrupt
@@ -1837,6 +1877,15 @@ void __init trap_init(void)
 			ebase += (read_c0_ebase() & 0x3ffff000);
 	}
 
+	if (cpu_has_mmips) {
+		unsigned int config3 = read_c0_config3();
+
+		if (IS_ENABLED(CONFIG_CPU_MICROMIPS))
+			write_c0_config3(config3 | MIPS_CONF3_ISA_OE);
+		else
+			write_c0_config3(config3 & ~MIPS_CONF3_ISA_OE);
+	}
+
 	if (board_ebase_setup)
 		board_ebase_setup();
 	per_cpu_trap_init(true);
@@ -1956,7 +2005,6 @@ void __init trap_init(void)
 		set_handler(0x080, &except_vec3_generic, 0x80);
 
 	local_flush_icache_range(ebase, ebase + 0x400);
-	flush_tlb_handlers();
 
 	sort_extable(__start___dbe_table, __stop___dbe_table);
 

arch/mips/kernel/unaligned.c

@@ -72,6 +72,7 @@
  *	 A store crossing a page boundary might be executed only partially.
  *	 Undo the partial store in this case.
  */
+#include <linux/context_tracking.h>
 #include <linux/mm.h>
 #include <linux/signal.h>
 #include <linux/smp.h>
@@ -684,7 +685,8 @@ const int reg16to32[] = { 16, 17, 2, 3, 4, 5, 6, 7 };
 /* Recode table from 16-bit STORE register notation to 32-bit GPR. */
 const int reg16to32st[] = { 0, 17, 2, 3, 4, 5, 6, 7 };
 
-void emulate_load_store_microMIPS(struct pt_regs *regs, void __user * addr)
+static void emulate_load_store_microMIPS(struct pt_regs *regs,
+					 void __user *addr)
 {
 	unsigned long value;
 	unsigned int res;
@@ -1548,11 +1550,14 @@ sigill:
 	    ("Unhandled kernel unaligned access or invalid instruction", regs);
 	force_sig(SIGILL, current);
 }
+
 asmlinkage void do_ade(struct pt_regs *regs)
 {
+	enum ctx_state prev_state;
 	unsigned int __user *pc;
 	mm_segment_t seg;
 
+	prev_state = exception_enter();
 	perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS,
 			1, regs, regs->cp0_badvaddr);
 	/*
@@ -1628,6 +1633,7 @@ sigbus:
 	/*
 	 * XXX On return from the signal handler we should advance the epc
 	 */
+	exception_exit(prev_state);
 }
 
 #ifdef CONFIG_DEBUG_FS

arch/mips/kernel/watch.c

@@ -111,6 +111,7 @@ __cpuinit void mips_probe_watch_registers(struct cpuinfo_mips *c)
 	 * disable the register.
 	 */
 	write_c0_watchlo0(7);
+	back_to_back_c0_hazard();
 	t = read_c0_watchlo0();
 	write_c0_watchlo0(0);
 	c->watch_reg_masks[0] = t & 7;
@@ -121,12 +122,14 @@ __cpuinit void mips_probe_watch_registers(struct cpuinfo_mips *c)
 	c->watch_reg_use_cnt = 1;
 	t = read_c0_watchhi0();
 	write_c0_watchhi0(t | 0xff8);
+	back_to_back_c0_hazard();
 	t = read_c0_watchhi0();
 	c->watch_reg_masks[0] |= (t & 0xff8);
 	if ((t & 0x80000000) == 0)
 		return;
 
 	write_c0_watchlo1(7);
+	back_to_back_c0_hazard();
 	t = read_c0_watchlo1();
 	write_c0_watchlo1(0);
 	c->watch_reg_masks[1] = t & 7;
@@ -135,12 +138,14 @@ __cpuinit void mips_probe_watch_registers(struct cpuinfo_mips *c)
 	c->watch_reg_use_cnt = 2;
 	t = read_c0_watchhi1();
 	write_c0_watchhi1(t | 0xff8);
+	back_to_back_c0_hazard();
 	t = read_c0_watchhi1();
 	c->watch_reg_masks[1] |= (t & 0xff8);
 	if ((t & 0x80000000) == 0)
 		return;
 
 	write_c0_watchlo2(7);
+	back_to_back_c0_hazard();
 	t = read_c0_watchlo2();
 	write_c0_watchlo2(0);
 	c->watch_reg_masks[2] = t & 7;
@@ -149,12 +154,14 @@ __cpuinit void mips_probe_watch_registers(struct cpuinfo_mips *c)
 	c->watch_reg_use_cnt = 3;
 	t = read_c0_watchhi2();
 	write_c0_watchhi2(t | 0xff8);
+	back_to_back_c0_hazard();
 	t = read_c0_watchhi2();
 	c->watch_reg_masks[2] |= (t & 0xff8);
 	if ((t & 0x80000000) == 0)
 		return;
 
 	write_c0_watchlo3(7);
+	back_to_back_c0_hazard();
 	t = read_c0_watchlo3();
 	write_c0_watchlo3(0);
 	c->watch_reg_masks[3] = t & 7;
@@ -163,6 +170,7 @@ __cpuinit void mips_probe_watch_registers(struct cpuinfo_mips *c)
 	c->watch_reg_use_cnt = 4;
 	t = read_c0_watchhi3();
 	write_c0_watchhi3(t | 0xff8);
+	back_to_back_c0_hazard();
 	t = read_c0_watchhi3();
 	c->watch_reg_masks[3] |= (t & 0xff8);
 	if ((t & 0x80000000) == 0)