Merge branch 'master' into for-linus

2 files changed, 13 insertions, 11 deletions

diff --git a/arch/x86/kernel/apic/ipi.c b/arch/x86/kernel/apic/ipi.c
index dbf5445727a9..6ef00ba4c886 100644
--- a/arch/x86/kernel/apic/ipi.c
+++ b/arch/x86/kernel/apic/ipi.c
@@ -106,6 +106,9 @@ void default_send_IPI_mask_logical(const struct cpumask *cpumask, int vector)
 	unsigned long mask = cpumask_bits(cpumask)[0];
 	unsigned long flags;
 
+	if (WARN_ONCE(!mask, "empty IPI mask"))
+		return;
+
 	local_irq_save(flags);
 	WARN_ON(mask & ~cpumask_bits(cpu_online_mask)[0]);
 	__default_send_IPI_dest_field(mask, vector, apic->dest_logical);
diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c
index 821e97017e95..c814e144a3f0 100644
--- a/arch/x86/mm/tlb.c
+++ b/arch/x86/mm/tlb.c
@@ -183,18 +183,17 @@ static void flush_tlb_others_ipi(const struct cpumask *cpumask,
 
 	f->flush_mm = mm;
 	f->flush_va = va;
-	cpumask_andnot(to_cpumask(f->flush_cpumask),
-		       cpumask, cpumask_of(smp_processor_id()));
-
-	/*
-	 * We have to send the IPI only to
-	 * CPUs affected.
-	 */
-	apic->send_IPI_mask(to_cpumask(f->flush_cpumask),
-		      INVALIDATE_TLB_VECTOR_START + sender);
+	if (cpumask_andnot(to_cpumask(f->flush_cpumask), cpumask, cpumask_of(smp_processor_id()))) {
+		/*
+		 * We have to send the IPI only to
+		 * CPUs affected.
+		 */
+		apic->send_IPI_mask(to_cpumask(f->flush_cpumask),
+			      INVALIDATE_TLB_VECTOR_START + sender);
 
-	while (!cpumask_empty(to_cpumask(f->flush_cpumask)))
-		cpu_relax();
+		while (!cpumask_empty(to_cpumask(f->flush_cpumask)))
+			cpu_relax();
+	}
 
 	f->flush_mm = NULL;
 	f->flush_va = 0;