1 files changed, 7 insertions, 1 deletions

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 82f29e70d058..6b9333b429ba 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1101,14 +1101,20 @@ int is_debug_stack(unsigned long addr)
                  addr > (__get_cpu_var(debug_stack_addr) - DEBUG_STKSZ));
 }
 
+static DEFINE_PER_CPU(u32, debug_stack_use_ctr);
+
 void debug_stack_set_zero(void)
 {
+        this_cpu_inc(debug_stack_use_ctr);
         load_idt((const struct desc_ptr *)&nmi_idt_descr);
 }
 
 void debug_stack_reset(void)
 {
-        load_idt((const struct desc_ptr *)&idt_descr);
+        if (WARN_ON(!this_cpu_read(debug_stack_use_ctr)))
+                return;
+        if (this_cpu_dec_return(debug_stack_use_ctr) == 0)
+                load_idt((const struct desc_ptr *)&idt_descr);
 }
 
 #else   /* CONFIG_X86_64 */