1 files changed, 15 insertions, 0 deletions

diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c
index e88f37b58dd..de8d4b333f4 100644
--- a/arch/x86/kernel/nmi.c
+++ b/arch/x86/kernel/nmi.c
@@ -408,6 +408,18 @@ static notrace __kprobes void default_do_nmi(struct pt_regs *regs)
 dotraplinkage notrace __kprobes void
 do_nmi(struct pt_regs *regs, long error_code)
 {
+        int update_debug_stack = 0;
+
+        /*
+         * If we interrupted a breakpoint, it is possible that
+         * the nmi handler will have breakpoints too. We need to
+         * change the IDT such that breakpoints that happen here
+         * continue to use the NMI stack.
+         */
+        if (unlikely(is_debug_stack(regs->sp))) {
+                debug_stack_set_zero();
+                update_debug_stack = 1;
+        }
         nmi_enter();
 
         inc_irq_stat(__nmi_count);
@@ -416,6 +428,9 @@ do_nmi(struct pt_regs *regs, long error_code)
                 default_do_nmi(regs);
 
         nmi_exit();
+
+        if (unlikely(update_debug_stack))
+                debug_stack_reset();
 }
 
 void stop_nmi(void)