Merge tag 'irq-core-2025-09-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irq core updates from Thomas Gleixner:
 "A set of updates for the interrupt core subsystem:

   - Introduce irq_chip_[startup|shutdown]_parent() to prepare for
     addressing a few short comings in the PCI/MSI interrupt subsystem.

     It allows to utilize the interrupt chip startup/shutdown callbacks
     for initializing the interrupt chip hierarchy properly on certain
     RISCV implementations and provides a mechanism to reduce the
     overhead of masking and unmasking PCI/MSI interrupts during
     operation when the underlying MSI provider can mask the interrupt.

     The actual usage comes with the interrupt driver pull request.

   - Add generic error handling for devm_request_*_irq()

     This allows to remove the zoo of random error printk's all over the
     usage sites.

   - Add a mechanism to warn about long-running interrupt handlers

     Long running interrupt handlers can introduce latencies and
     tracking them down is a tedious task. The tracking has to be
     enabled with a threshold on the kernel command line and utilizes a
     static branch to remove the overhead when disabled.

   - Update and extend the selftests which validate the CPU hotplug
     interrupt migration logic

   - Allow dropping the per CPU softirq lock on PREEMPT_RT kernels,
     which causes contention and latencies all over the place.

     The serialization requirements have been pushed down into the
     actual affected usage sites already.

   - The usual small cleanups and improvements"

* tag 'irq-core-2025-09-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  softirq: Allow to drop the softirq-BKL lock on PREEMPT_RT
  softirq: Provide a handshake for canceling tasklets via polling
  genirq/test: Ensure CPU 1 is online for hotplug test
  genirq/test: Drop CONFIG_GENERIC_IRQ_MIGRATION assumptions
  genirq/test: Depend on SPARSE_IRQ
  genirq/test: Fail early if interrupt request fails
  genirq/test: Factor out fake-virq setup
  genirq/test: Select IRQ_DOMAIN
  genirq/test: Fix depth tests on architectures with NOREQUEST by default.
  genirq: Add support for warning on long-running interrupt handlers
  genirq/devres: Add error handling in devm_request_*_irq()
  genirq: Add irq_chip_(startup/shutdown)_parent()
  genirq: Remove GENERIC_IRQ_LEGACY

1 files changed, 30 insertions, 25 deletions

diff --git a/kernel/irq/irq_test.c b/kernel/irq/irq_test.c
index a75abebed7f2..e2d31914b3c4 100644
--- a/kernel/irq/irq_test.c
+++ b/kernel/irq/irq_test.c
@@ -41,21 +41,37 @@ static struct irq_chip fake_irq_chip = {
 	.flags          = IRQCHIP_SKIP_SET_WAKE,
 };
 
-static void irq_disable_depth_test(struct kunit *test)
+static int irq_test_setup_fake_irq(struct kunit *test, struct irq_affinity_desc *affd)
 {
 	struct irq_desc *desc;
-	int virq, ret;
+	int virq;
 
-	virq = irq_domain_alloc_descs(-1, 1, 0, NUMA_NO_NODE, NULL);
+	virq = irq_domain_alloc_descs(-1, 1, 0, NUMA_NO_NODE, affd);
 	KUNIT_ASSERT_GE(test, virq, 0);
 
-	irq_set_chip_and_handler(virq, &dummy_irq_chip, handle_simple_irq);
+	irq_set_chip_and_handler(virq, &fake_irq_chip, handle_simple_irq);
+
+	desc = irq_to_desc(virq);
+	KUNIT_ASSERT_PTR_NE(test, desc, NULL);
+
+	/* On some architectures, IRQs are NOREQUEST | NOPROBE by default. */
+	irq_settings_clr_norequest(desc);
+
+	return virq;
+}
+
+static void irq_disable_depth_test(struct kunit *test)
+{
+	struct irq_desc *desc;
+	int virq, ret;
+
+	virq = irq_test_setup_fake_irq(test, NULL);
 
 	desc = irq_to_desc(virq);
 	KUNIT_ASSERT_PTR_NE(test, desc, NULL);
 
 	ret = request_irq(virq, noop_handler, 0, "test_irq", NULL);
-	KUNIT_EXPECT_EQ(test, ret, 0);
+	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	KUNIT_EXPECT_EQ(test, desc->depth, 0);
 
@@ -73,16 +89,13 @@ static void irq_free_disabled_test(struct kunit *test)
 	struct irq_desc *desc;
 	int virq, ret;
 
-	virq = irq_domain_alloc_descs(-1, 1, 0, NUMA_NO_NODE, NULL);
-	KUNIT_ASSERT_GE(test, virq, 0);
-
-	irq_set_chip_and_handler(virq, &dummy_irq_chip, handle_simple_irq);
+	virq = irq_test_setup_fake_irq(test, NULL);
 
 	desc = irq_to_desc(virq);
 	KUNIT_ASSERT_PTR_NE(test, desc, NULL);
 
 	ret = request_irq(virq, noop_handler, 0, "test_irq", NULL);
-	KUNIT_EXPECT_EQ(test, ret, 0);
+	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	KUNIT_EXPECT_EQ(test, desc->depth, 0);
 
@@ -93,7 +106,7 @@ static void irq_free_disabled_test(struct kunit *test)
 	KUNIT_EXPECT_GE(test, desc->depth, 1);
 
 	ret = request_irq(virq, noop_handler, 0, "test_irq", NULL);
-	KUNIT_EXPECT_EQ(test, ret, 0);
+	KUNIT_ASSERT_EQ(test, ret, 0);
 	KUNIT_EXPECT_EQ(test, desc->depth, 0);
 
 	free_irq(virq, NULL);
@@ -112,10 +125,7 @@ static void irq_shutdown_depth_test(struct kunit *test)
 	if (!IS_ENABLED(CONFIG_SMP))
 		kunit_skip(test, "requires CONFIG_SMP for managed shutdown");
 
-	virq = irq_domain_alloc_descs(-1, 1, 0, NUMA_NO_NODE, &affinity);
-	KUNIT_ASSERT_GE(test, virq, 0);
-
-	irq_set_chip_and_handler(virq, &dummy_irq_chip, handle_simple_irq);
+	virq = irq_test_setup_fake_irq(test, &affinity);
 
 	desc = irq_to_desc(virq);
 	KUNIT_ASSERT_PTR_NE(test, desc, NULL);
@@ -124,7 +134,7 @@ static void irq_shutdown_depth_test(struct kunit *test)
 	KUNIT_ASSERT_PTR_NE(test, data, NULL);
 
 	ret = request_irq(virq, noop_handler, 0, "test_irq", NULL);
-	KUNIT_EXPECT_EQ(test, ret, 0);
+	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	KUNIT_EXPECT_TRUE(test, irqd_is_activated(data));
 	KUNIT_EXPECT_TRUE(test, irqd_is_started(data));
@@ -169,13 +179,12 @@ static void irq_cpuhotplug_test(struct kunit *test)
 		kunit_skip(test, "requires more than 1 CPU for CPU hotplug");
 	if (!cpu_is_hotpluggable(1))
 		kunit_skip(test, "CPU 1 must be hotpluggable");
+	if (!cpu_online(1))
+		kunit_skip(test, "CPU 1 must be online");
 
 	cpumask_copy(&affinity.mask, cpumask_of(1));
 
-	virq = irq_domain_alloc_descs(-1, 1, 0, NUMA_NO_NODE, &affinity);
-	KUNIT_ASSERT_GE(test, virq, 0);
-
-	irq_set_chip_and_handler(virq, &fake_irq_chip, handle_simple_irq);
+	virq = irq_test_setup_fake_irq(test, &affinity);
 
 	desc = irq_to_desc(virq);
 	KUNIT_ASSERT_PTR_NE(test, desc, NULL);
@@ -184,7 +193,7 @@ static void irq_cpuhotplug_test(struct kunit *test)
 	KUNIT_ASSERT_PTR_NE(test, data, NULL);
 
 	ret = request_irq(virq, noop_handler, 0, "test_irq", NULL);
-	KUNIT_EXPECT_EQ(test, ret, 0);
+	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	KUNIT_EXPECT_TRUE(test, irqd_is_activated(data));
 	KUNIT_EXPECT_TRUE(test, irqd_is_started(data));
@@ -196,13 +205,9 @@ static void irq_cpuhotplug_test(struct kunit *test)
 	KUNIT_EXPECT_EQ(test, desc->depth, 1);
 
 	KUNIT_EXPECT_EQ(test, remove_cpu(1), 0);
-	KUNIT_EXPECT_FALSE(test, irqd_is_activated(data));
-	KUNIT_EXPECT_FALSE(test, irqd_is_started(data));
 	KUNIT_EXPECT_GE(test, desc->depth, 1);
 	KUNIT_EXPECT_EQ(test, add_cpu(1), 0);
 
-	KUNIT_EXPECT_FALSE(test, irqd_is_activated(data));
-	KUNIT_EXPECT_FALSE(test, irqd_is_started(data));
 	KUNIT_EXPECT_EQ(test, desc->depth, 1);
 
 	enable_irq(virq);