diff -Nru linux/arch/mips/mm/tlb-sb1.c.orig linux/arch/mips/mm/tlb-sb1.c
--- linux/arch/mips/mm/tlb-sb1.c.orig	Wed Dec 11 17:04:17 2002
+++ linux/arch/mips/mm/tlb-sb1.c	Tue Feb  4 15:00:53 2003
@@ -172,15 +172,7 @@
 			}
 			write_c0_entryhi(oldpid);
 		} else {
-			get_new_mmu_context(mm, cpu);
-			if (mm == current->active_mm) {
-				write_c0_entryhi(cpu_asid(cpu, mm));
-			} else if (!(cpu_asid(cpu, mm)) &&
-				   cpu_context(cpu, current->active_mm)) {
-				/* Just wrapped ASIDs, bump the active one */
-				get_new_mmu_context(current->active_mm, cpu);
-				write_c0_entryhi(cpu_context(cpu, current->active_mm)& 0xff);
-			}
+			drop_mmu_context(mm, cpu);
 		}
 	}
 	local_irq_restore(flags);
@@ -325,17 +317,10 @@
    these entries, we just bump the asid. */
 void local_flush_tlb_mm(struct mm_struct *mm)
 {
-	unsigned long flags;
-	int cpu;
-	local_irq_save(flags);
-	cpu = smp_processor_id();
+	int cpu = smp_processor_id();
 	if (cpu_context(cpu, mm) != 0) {
-		get_new_mmu_context(mm, smp_processor_id());
-		if (mm == current->active_mm) {
-			write_c0_entryhi(cpu_context(cpu, mm) & 0xff);
-		}
+		drop_mmu_context(mm, cpu);
 	}
-	local_irq_restore(flags);
 }
 
 /* Stolen from mips32 routines */
diff -Nru linux/arch/mips/mm/tlb-r4k.c.orig linux/arch/mips/mm/tlb-r4k.c
--- linux/arch/mips/mm/tlb-r4k.c.orig	Mon Jan 27 18:03:21 2003
+++ linux/arch/mips/mm/tlb-r4k.c	Tue Feb  4 15:04:29 2003
@@ -76,16 +76,10 @@
 	int cpu = smp_processor_id();
 
 	if (cpu_context(cpu, mm) != 0) {
-		unsigned long flags;
-
 #ifdef DEBUG_TLB
 		printk("[tlbmm<%d>]", cpu_context(cpu, mm));
 #endif
-		local_irq_save(flags);
-		get_new_mmu_context(mm, smp_processor_id());
-		if (mm == current->active_mm)
-			write_c0_entryhi(cpu_context(cpu, mm) & ASID_MASK);
-		local_irq_restore(flags);
+		drop_mmu_context(mm,cpu);
 	}
 }
 
@@ -134,9 +128,7 @@
 			}
 			write_c0_entryhi(oldpid);
 		} else {
-			get_new_mmu_context(mm, smp_processor_id());
-			if (mm == current->active_mm)
-				write_c0_entryhi(cpu_context(cpu, mm) & ASID_MASK);
+			drop_mmu_context(mm, cpu);
 		}
 		local_irq_restore(flags);
 	}
diff -Nru linux/arch/mips/mm/tlb-r3k.c.orig linux/arch/mips/mm/tlb-r3k.c
--- linux/arch/mips/mm/tlb-r3k.c.orig	Mon Jan 27 18:03:21 2003
+++ linux/arch/mips/mm/tlb-r3k.c	Tue Feb  4 15:05:22 2003
@@ -69,16 +69,10 @@
 	int cpu = smp_processor_id();
 
 	if (cpu_context(cpu, mm) != 0) {
-		unsigned long flags;
-
 #ifdef DEBUG_TLB
 		printk("[tlbmm<%lu>]", (unsigned long)cpu_context(cpu, mm));
 #endif
-		local_irq_save(flags);
-		get_new_mmu_context(mm, cpu);
-		if (mm == current->active_mm)
-			write_c0_entryhi(cpu_context(cpu, mm) & ASID_MASK);
-		local_irq_restore(flags);
+		drop_mmu_context(mm, cpu);
 	}
 }
 
@@ -120,9 +114,7 @@
 			}
 			write_c0_entryhi(oldpid);
 		} else {
-			get_new_mmu_context(mm, smp_processor_id());
-			if (mm == current->active_mm)
-				write_c0_entryhi(cpu_context(cpu, mm) & ASID_MASK);
+			drop_mmu_context(mm, cpu);
 		}
 		local_irq_restore(flags);
 	}
diff -Nru linux/arch/mips64/mm/tlb-sb1.c.orig linux/arch/mips64/mm/tlb-sb1.c
--- linux/arch/mips64/mm/tlb-sb1.c.orig	Wed Dec 11 17:04:19 2002
+++ linux/arch/mips64/mm/tlb-sb1.c	Tue Feb  4 15:07:42 2003
@@ -180,9 +180,7 @@
 			}
 			write_c0_entryhi(oldpid);
 		} else {
-			get_new_mmu_context(mm, cpu);
-			if (mm == current->active_mm)
-				write_c0_entryhi(cpu_context(cpu, mm) & 0xff);
+			drop_mmu_context(mm, cpu);
 		}
 	}
 	local_irq_restore(flags);
@@ -268,17 +266,10 @@
    these entries, we just bump the asid. */
 void local_flush_tlb_mm(struct mm_struct *mm)
 {
-	unsigned long flags;
-	int cpu;
-	local_irq_save(flags);
-	cpu = smp_processor_id();
+	int cpu = smp_processor_id();
 	if (cpu_context(cpu, mm) != 0) {
-		get_new_mmu_context(mm, smp_processor_id());
-		if (mm == current->active_mm) {
-			write_c0_entryhi(cpu_context(cpu, mm) & 0xff);
-		}
+		drop_mmu_context(mm, cpu);
 	}
-	local_irq_restore(flags);
 }
 
 /* Stolen from mips32 routines */
diff -Nru linux/arch/mips64/mm/tlb-r4k.c.orig linux/arch/mips64/mm/tlb-r4k.c
--- linux/arch/mips64/mm/tlb-r4k.c.orig	Mon Jan 27 18:03:22 2003
+++ linux/arch/mips64/mm/tlb-r4k.c	Tue Feb  4 15:08:21 2003
@@ -80,16 +80,10 @@
 	int cpu = smp_processor_id();
 
 	if (cpu_context(cpu, mm) != 0) {
-		unsigned long flags;
-
 #ifdef DEBUG_TLB
 		printk("[tlbmm<%d>]", cpu_context(cpu, mm));
 #endif
-		local_irq_save(flags);
-		get_new_mmu_context(mm, cpu);
-		if (mm == current->active_mm)
-			write_c0_entryhi(cpu_asid(cpu, mm));
-		local_irq_restore(flags);
+		drop_mmu_context(mm,cpu);
 	}
 }
 
@@ -138,9 +132,7 @@
 			}
 			write_c0_entryhi(oldpid);
 		} else {
-			get_new_mmu_context(mm, cpu);
-			if (mm == current->active_mm)
-				write_c0_entryhi(cpu_asid(cpu, mm));
+			drop_mmu_context(mm, cpu);
 		}
 		local_irq_restore(flags);
 	}
diff -Nru linux/arch/mips64/mm/tlb-andes.c.orig linux/arch/mips64/mm/tlb-andes.c
--- linux/arch/mips64/mm/tlb-andes.c.orig	Tue Feb  4 13:14:43 2003
+++ linux/arch/mips64/mm/tlb-andes.c	Tue Feb  4 14:53:28 2003
@@ -53,18 +53,12 @@
 
 void local_flush_tlb_mm(struct mm_struct *mm)
 {
-	if (cpu_context(smp_processor_id(), mm) != 0) {
-		unsigned long flags;
-
+	int cpu = smp_processor_id();
+	if (cpu_context(cpu, mm) != 0) {
 #ifdef DEBUG_TLB
 		printk("[tlbmm<%d>]", mm->context);
 #endif
-		local_irq_save(flags);
-		get_new_mmu_context(mm, smp_processor_id());
-		if (mm == current->active_mm)
-			write_c0_entryhi(cpu_context(smp_processor_id(), mm)
-				    & ASID_MASK);
-		local_irq_restore(flags);
+		drop_mmu_context(mm,cpu);
 	}
 }
 
@@ -108,10 +102,7 @@
 			}
 			write_c0_entryhi(oldpid);
 		} else {
-			get_new_mmu_context(mm, smp_processor_id());
-			if (mm == current->active_mm)
-				write_c0_entryhi(cpu_context(smp_processor_id(), mm)
-					    & ASID_MASK);
+			drop_mmu_context(mm, cpu);
 		}
 		local_irq_restore(flags);
 	}
diff -Nru linux/include/asm-mips/mmu_context.h.orig linux/include/asm-mips/mmu_context.h
--- linux/include/asm-mips/mmu_context.h.orig	Mon Jan 27 18:03:23 2003
+++ linux/include/asm-mips/mmu_context.h	Tue Feb  4 14:53:28 2003
@@ -92,12 +92,25 @@
 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
                              struct task_struct *tsk, unsigned cpu)
 {
+	unsigned long flags;
+
+	local_irq_save(flags);
+
 	/* Check if our ASID is of an older version and thus invalid */
 	if ((cpu_context(cpu, next) ^ asid_cache(cpu)) & ASID_VERSION_MASK)
 		get_new_mmu_context(next, cpu);
 
 	write_c0_entryhi(cpu_context(cpu, next));
 	TLBMISS_HANDLER_SETUP_PGD(next->pgd);
+
+	/*
+	 * Mark current->active_mm as not "active" anymore.
+	 * We don't want to mislead possible IPI tlb flush routines.
+	 */
+	clear_bit(cpu, &prev->cpu_vm_mask);
+	set_bit(cpu, &next->cpu_vm_mask);
+
+	local_irq_restore(flags);
 }
 
 /*
@@ -115,11 +128,39 @@
 static inline void
 activate_mm(struct mm_struct *prev, struct mm_struct *next)
 {
+	unsigned long flags;
+
+	local_irq_save(flags);
+
 	/* Unconditionally get a new ASID.  */
 	get_new_mmu_context(next, smp_processor_id());
 
 	write_c0_entryhi(cpu_context(smp_processor_id(), next));
 	TLBMISS_HANDLER_SETUP_PGD(next->pgd);
+	
+	local_irq_restore(flags);
+}
+
+/*
+ * If mm is currently active_mm, we can't really drop it.  Instead,
+ * we will get a new one for it.
+ */
+static inline void
+drop_mmu_context(struct mm_struct *mm, unsigned cpu)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+
+	if (test_bit(cpu, &mm->cpu_vm_mask))  {
+		get_new_mmu_context(mm, cpu);
+		set_entryhi(CPU_CONTEXT(cpu, mm) & 0xff);
+	} else {
+		/* will get a new context next time */
+		CPU_CONTEXT(cpu, mm) = 0;
+	}
+
+	local_irq_restore(flags);
 }
 
 #endif /* _ASM_MMU_CONTEXT_H */
diff -Nru linux/include/asm-mips64/mmu_context.h.orig linux/include/asm-mips64/mmu_context.h
--- linux/include/asm-mips64/mmu_context.h.orig	Mon Jan 27 18:03:23 2003
+++ linux/include/asm-mips64/mmu_context.h	Tue Feb  4 14:53:28 2003
@@ -83,12 +83,25 @@
 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
                              struct task_struct *tsk, unsigned cpu)
 {
+	unsigned long flags;
+
+	local_irq_save(flags);
+
 	/* Check if our ASID is of an older version and thus invalid */
 	if ((cpu_context(cpu, next) ^ asid_cache(cpu)) & ASID_VERSION_MASK)
 		get_new_mmu_context(next, cpu);
 
 	write_c0_entryhi(cpu_context(cpu, next));
 	TLBMISS_HANDLER_SETUP_PGD(next->pgd);
+
+	/*
+	 * Mark current->active_mm as not "active" anymore.
+	 * We don't want to mislead possible IPI tlb flush routines.
+	 */
+	clear_bit(cpu, &prev->cpu_vm_mask);
+	set_bit(cpu, &next->cpu_vm_mask);
+
+	local_irq_restore(flags);
 }
 
 /*
@@ -106,11 +119,39 @@
 static inline void
 activate_mm(struct mm_struct *prev, struct mm_struct *next)
 {
+	unsigned long flags;
+
+	local_irq_save(flags);
+
 	/* Unconditionally get a new ASID.  */
 	get_new_mmu_context(next, smp_processor_id());
 
 	write_c0_entryhi(cpu_context(smp_processor_id(), next));
 	TLBMISS_HANDLER_SETUP_PGD(next->pgd);
+	
+	local_irq_restore(flags);
+}
+
+/*
+ * If mm is currently active_mm, we can't really drop it.  Instead,
+ * we will get a new one for it.
+ */
+static inline void
+drop_mmu_context(struct mm_struct *mm, unsigned cpu)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+
+	if (test_bit(cpu, &mm->cpu_vm_mask))  {
+		get_new_mmu_context(mm, cpu);
+		set_entryhi(CPU_CONTEXT(cpu, mm) & 0xff);
+	} else {
+		/* will get a new context next time */
+		CPU_CONTEXT(cpu, mm) = 0;
+	}
+
+	local_irq_restore(flags);
 }
 
 #endif /* _ASM_MMU_CONTEXT_H */