--- zzzz-none-000/linux-2.6.39.4/arch/x86/kernel/apic/hw_nmi.c	2011-08-03 19:43:28.000000000 +0000
+++ puma6-atom-6490-729/linux-2.6.39.4/arch/x86/kernel/apic/hw_nmi.c	2021-11-10 13:38:14.000000000 +0000
@@ -32,8 +32,9 @@
 /* "in progress" flag of arch_trigger_all_cpu_backtrace */
 static unsigned long backtrace_flag;
 
-void arch_trigger_all_cpu_backtrace(void)
+static void __arch_trigger_all_cpu_backtrace(bool exclude_self)
 {
+	int this_cpu = get_cpu();
 	int i;
 
 	if (test_and_set_bit(0, &backtrace_flag))
@@ -45,8 +46,14 @@
 
 	cpumask_copy(to_cpumask(backtrace_mask), cpu_online_mask);
 
-	printk(KERN_INFO "sending NMI to all CPUs:\n");
-	apic->send_IPI_all(NMI_VECTOR);
+	printk(KERN_INFO "sending NMI to all %sCPUs:\n",
+			exclude_self ? "other " : "");
+	if (exclude_self) {
+		cpumask_clear_cpu(this_cpu, to_cpumask(backtrace_mask));
+		apic->send_IPI_allbutself(NMI_VECTOR);
+	} else {
+		apic->send_IPI_all(NMI_VECTOR);
+	}
 
 	/* Wait for up to 10 seconds for all CPUs to do the backtrace */
 	for (i = 0; i < 10 * 1000; i++) {
@@ -57,6 +64,19 @@
 
 	clear_bit(0, &backtrace_flag);
 	smp_mb__after_clear_bit();
+
+	put_cpu();
+}
+
+
+void arch_trigger_allbutself_cpu_backtrace(void)
+{
+	__arch_trigger_all_cpu_backtrace(true);
+}
+
+void arch_trigger_all_cpu_backtrace(void)
+{
+	__arch_trigger_all_cpu_backtrace(false);
 }
 
 static int __kprobes