1 files changed, 3 insertions, 0 deletions

diff --git a/lib/nmi_backtrace.c b/lib/nmi_backtrace.c
index 4e8a30d1c22f..0bc0a3535a8a 100644
--- a/lib/nmi_backtrace.c
+++ b/lib/nmi_backtrace.c
@@ -86,9 +86,11 @@ void nmi_trigger_cpumask_backtrace(const cpumask_t *mask,
 
 bool nmi_cpu_backtrace(struct pt_regs *regs)
 {
+        static arch_spinlock_t lock = __ARCH_SPIN_LOCK_UNLOCKED;
         int cpu = smp_processor_id();
 
         if (cpumask_test_cpu(cpu, to_cpumask(backtrace_mask))) {
+                arch_spin_lock(&lock);
                 if (regs && cpu_in_idle(instruction_pointer(regs))) {
                         pr_warn("NMI backtrace for cpu %d skipped: idling at pc %#lx\n",
                                 cpu, instruction_pointer(regs));
@@ -99,6 +101,7 @@ bool nmi_cpu_backtrace(struct pt_regs *regs)
                         else
                                 dump_stack();
                 }
+                arch_spin_unlock(&lock);
                 cpumask_clear_cpu(cpu, to_cpumask(backtrace_mask));
                 return true;
         }