x86/mm: Don't reenter flush_tlb_func_common()

[linux.git] / arch / x86 / mm / tlb.c

diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c
index b2485d69f7c2c593d921bc2267c2b898ae0a4da6..1cc47838d1e817b3579f7b78c64ee5ead263ffb4 100644 (file)
--- a/arch/x86/mm/tlb.c
+++ b/arch/x86/mm/tlb.c
@@ -192,6 +192,9 @@ void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next,
 static void flush_tlb_func_common(const struct flush_tlb_info *f,
                                  bool local, enum tlb_flush_reason reason)
 {
+       /* This code cannot presently handle being reentered. */
+       VM_WARN_ON(!irqs_disabled());
+
        if (this_cpu_read(cpu_tlbstate.state) != TLBSTATE_OK) {
                leave_mm(smp_processor_id());
                return;
@@ -297,8 +300,13 @@ void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start,
                info.end = TLB_FLUSH_ALL;
        }
 
-       if (mm == this_cpu_read(cpu_tlbstate.loaded_mm))
+       if (mm == this_cpu_read(cpu_tlbstate.loaded_mm)) {
+               VM_WARN_ON(irqs_disabled());
+               local_irq_disable();
                flush_tlb_func_local(&info, TLB_LOCAL_MM_SHOOTDOWN);
+               local_irq_enable();
+       }
+
        if (cpumask_any_but(mm_cpumask(mm), cpu) < nr_cpu_ids)
                flush_tlb_others(mm_cpumask(mm), &info);
        put_cpu();
@@ -354,8 +362,13 @@ void arch_tlbbatch_flush(struct arch_tlbflush_unmap_batch *batch)
 
        int cpu = get_cpu();
 
-       if (cpumask_test_cpu(cpu, &batch->cpumask))
+       if (cpumask_test_cpu(cpu, &batch->cpumask)) {
+               VM_WARN_ON(irqs_disabled());
+               local_irq_disable();
                flush_tlb_func_local(&info, TLB_LOCAL_SHOOTDOWN);
+               local_irq_enable();
+       }
+
        if (cpumask_any_but(&batch->cpumask, cpu) < nr_cpu_ids)
                flush_tlb_others(&batch->cpumask, &info);
        cpumask_clear(&batch->cpumask);