Merge branch 'topic/asoc' into for-linus

[firefly-linux-kernel-4.4.55.git] / arch / x86 / kernel / apic / nmi.c

diff --git a/arch/x86/kernel/apic/nmi.c b/arch/x86/kernel/apic/nmi.c
index d6bd6240715256f4947166f347c0ce1d296a440c..ce4fbfa315a16ac1f4e45f34281121577f5477a6 100644 (file)
--- a/arch/x86/kernel/apic/nmi.c
+++ b/arch/x86/kernel/apic/nmi.c
@@ -138,7 +138,7 @@ int __init check_nmi_watchdog(void)
        if (!prev_nmi_count)
                goto error;
 
-       alloc_cpumask_var(&backtrace_mask, GFP_KERNEL);
+       alloc_cpumask_var(&backtrace_mask, GFP_KERNEL|__GFP_ZERO);
        printk(KERN_INFO "Testing NMI watchdog ... ");
 
 #ifdef CONFIG_SMP
@@ -414,7 +414,8 @@ nmi_watchdog_tick(struct pt_regs *regs, unsigned reason)
                touched = 1;
        }
 
-       if (cpumask_test_cpu(cpu, backtrace_mask)) {
+       /* We can be called before check_nmi_watchdog, hence NULL check. */
+       if (backtrace_mask != NULL && cpumask_test_cpu(cpu, backtrace_mask)) {
                static DEFINE_SPINLOCK(lock);   /* Serialise the printks */
 
                spin_lock(&lock);