1 files changed, 8 insertions, 5 deletions

diff --git a/arch/x86/kernel/tlb_32.c b/arch/x86/kernel/tlb_32.c
index ec53818f4e38..d37bbfcb813d 100644
--- a/arch/x86/kernel/tlb_32.c
+++ b/arch/x86/kernel/tlb_32.c
@@ -125,9 +125,8 @@ void native_flush_tlb_others(const struct cpumask *cpumask,
                              struct mm_struct *mm, unsigned long va)
 {
         /*
-         * - mask must exist :)
+         * mm must exist :)
          */
-        BUG_ON(cpumask_empty(cpumask));
         BUG_ON(!mm);
 
         /*
@@ -138,14 +137,18 @@ void native_flush_tlb_others(const struct cpumask *cpumask,
         spin_lock(&tlbstate_lock);
 
         cpumask_andnot(flush_cpumask, cpumask, cpumask_of(smp_processor_id()));
-#ifdef CONFIG_HOTPLUG_CPU
-        /* If a CPU which we ran on has gone down, OK. */
         cpumask_and(flush_cpumask, flush_cpumask, cpu_online_mask);
+
+        /*
+         * If a task whose mm mask we are looking at has descheduled and
+         * has cleared its presence from the mask, or if a CPU which we ran
+         * on has gone down then there might be no flush work left:
+         */
         if (unlikely(cpumask_empty(flush_cpumask))) {
                 spin_unlock(&tlbstate_lock);
                 return;
         }
-#endif
+
         flush_mm = mm;
         flush_va = va;