Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c
index 59b5f2e..21efee3 100644
--- a/arch/x86/kernel/irq.c
+++ b/arch/x86/kernel/irq.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Common interrupt code for 32 and 64 bit
  */
@@ -134,7 +135,7 @@
 		seq_printf(p, "%10u ", per_cpu(mce_poll_count, j));
 	seq_puts(p, "  Machine check polls\n");
 #endif
-#if IS_ENABLED(CONFIG_HYPERV) || defined(CONFIG_XEN)
+#ifdef CONFIG_X86_HV_CALLBACK_VECTOR
 	if (test_bit(HYPERVISOR_CALLBACK_VECTOR, system_vectors)) {
 		seq_printf(p, "%*s: ", prec, "HYP");
 		for_each_online_cpu(j)
@@ -242,11 +243,15 @@
 	RCU_LOCKDEP_WARN(!rcu_is_watching(), "IRQ failed to wake up RCU");
 
 	desc = __this_cpu_read(vector_irq[vector]);
-
-	if (!handle_irq(desc, regs)) {
+	if (likely(!IS_ERR_OR_NULL(desc))) {
+		if (IS_ENABLED(CONFIG_X86_32))
+			handle_irq(desc, regs);
+		else
+			generic_handle_irq_desc(desc);
+	} else {
 		ack_APIC_irq();
 
-		if (desc != VECTOR_RETRIGGERED) {
+		if (desc == VECTOR_UNUSED) {
 			pr_emerg_ratelimited("%s: %d.%d No irq handler for vector\n",
 					     __func__, smp_processor_id(),
 					     vector);