These tests demonstrate bugs in the irq shutdown/startup code. See the
appended test report.
In summary, the latter two cases cover:
## shutdown depth:
disable_irq()
irq_shutdown_and_deactivate()
irq_activate_and_startup() <-- BUG: depth is 0 after this
enable_irq()
## cpu hotplug:
affine IRQ to CPU 1
disable_irq()
remove CPU 1
add CPU 1 <-- BUG: depth is 0 after this
enable_irq()
NB: since one of the tests intersects with CPU hotplug, these tests
requires SMP support. They can be easily run with:
$ tools/testing/kunit/kunit.py run 'irq_test_cases*' --arch x86_64 --qemu_args '-smp 2'
[13:24:21] =============== irq_test_cases (3 subtests) ================
[13:24:21] [PASSED] irq_disable_depth_test
[13:24:21] # irq_shutdown_depth_test: EXPECTATION FAILED at kernel/irq/irq_test.c:93
[13:24:21] Expected desc->depth == 1, but
[13:24:21] desc->depth == 0 (0x0)
[13:24:21] ------------[ cut here ]------------
[13:24:21] Unbalanced enable for IRQ 25
[13:24:21] WARNING: CPU: 1 PID: 34 at kernel/irq/manage.c:792 __enable_irq+0x36/0x60
...
[13:24:21] Call Trace:
[13:24:21] <TASK>
[13:24:21] enable_irq+0x4a/0x90
[13:24:21] irq_shutdown_depth_test+0x17b/0x3b0
[13:24:21] kunit_try_run_case+0x90/0x120
...
[13:24:21] </TASK>
[13:24:21] ---[ end trace 0000000000000000 ]---
[13:24:21] # irq_shutdown_depth_test.speed: slow
[13:24:21] [FAILED] irq_shutdown_depth_test
[13:24:21] #1
[13:24:21] # irq_cpuhotplug_test: EXPECTATION FAILED at kernel/irq/irq_test.c:140
[13:24:21] Expected desc->depth == 1, but
[13:24:21] desc->depth == 0 (0x0)
[13:24:21] ------------[ cut here ]------------
[13:24:21] Unbalanced enable for IRQ 26
[13:24:21] WARNING: CPU: 0 PID: 36 at kernel/irq/manage.c:792 __enable_irq+0x36/0x60
...
[13:24:21] Call Trace:
[13:24:21] <TASK>
[13:24:21] enable_irq+0x4a/0x90
[13:24:21] irq_cpuhotplug_test+0x28f/0x660
[13:24:21] kunit_try_run_case+0x90/0x120
...
[13:24:21] </TASK>
[13:24:21] ---[ end trace 0000000000000000 ]---
[13:24:21] # irq_cpuhotplug_test.speed: slow
[13:24:21] [FAILED] irq_cpuhotplug_test
[13:24:21] # module: irq_test
[13:24:21] # irq_test_cases: pass:1 fail:2 skip:0 total:3
[13:24:21] # Totals: pass:1 fail:2 skip:0 total:3
[13:24:21] ================= [FAILED] irq_test_cases ==================
[13:24:21] ============================================================
[13:24:21] Testing complete. Ran 3 tests: passed: 1, failed: 2
Also note that currently, these tests don't fully clean up after
themselves, as I didn't yet figure out all the right ways to set up a
fake virq and domain for the purpose of unit testing. They contain TODOs
to that effect.
Signed-off-by: Brian Norris <briannorris@chromium.org>
---
kernel/irq/Kconfig | 10 +++
kernel/irq/Makefile | 1 +
kernel/irq/irq_test.c | 162 ++++++++++++++++++++++++++++++++++++++++++
3 files changed, 173 insertions(+)
create mode 100644 kernel/irq/irq_test.c
diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig
index 3f02a0e45254..9295dabea4a0 100644
--- a/kernel/irq/Kconfig
+++ b/kernel/irq/Kconfig
@@ -144,6 +144,16 @@ config GENERIC_IRQ_DEBUGFS
config GENERIC_IRQ_KEXEC_CLEAR_VM_FORWARD
bool
+config IRQ_KUNIT_TEST
+ tristate "KUnit test for IRQ management APIs" if !KUNIT_ALL_TESTS
+ depends on KUNIT
+ default KUNIT_ALL_TESTS
+ select SMP
+ help
+ Enable this option to test IRQ management APIs.
+
+ If unsure, say N.
+
endmenu
config GENERIC_IRQ_MULTI_HANDLER
diff --git a/kernel/irq/Makefile b/kernel/irq/Makefile
index c0f44c06d69d..6ab3a4055667 100644
--- a/kernel/irq/Makefile
+++ b/kernel/irq/Makefile
@@ -19,3 +19,4 @@ obj-$(CONFIG_GENERIC_IRQ_IPI_MUX) += ipi-mux.o
obj-$(CONFIG_SMP) += affinity.o
obj-$(CONFIG_GENERIC_IRQ_DEBUGFS) += debugfs.o
obj-$(CONFIG_GENERIC_IRQ_MATRIX_ALLOCATOR) += matrix.o
+obj-$(CONFIG_IRQ_KUNIT_TEST) += irq_test.o
diff --git a/kernel/irq/irq_test.c b/kernel/irq/irq_test.c
new file mode 100644
index 000000000000..24f4d8e6c433
--- /dev/null
+++ b/kernel/irq/irq_test.c
@@ -0,0 +1,162 @@
+// SPDX-License-Identifier: LGPL-2.1+
+
+#include <linux/cpu.h>
+#include <linux/cpumask.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqdesc.h>
+#include <linux/irqdomain.h>
+#include <linux/nodemask.h>
+#include <kunit/test.h>
+
+#include "internals.h"
+
+static irqreturn_t noop_handler(int, void *)
+{
+ return IRQ_HANDLED;
+}
+
+static void noop(struct irq_data *data) { }
+static unsigned int noop_ret(struct irq_data *data) { return 0; }
+
+static int noop_affinity(struct irq_data *data, const struct cpumask *dest, bool force)
+{
+ irq_data_update_effective_affinity(data, dest);
+
+ return 0;
+}
+
+static struct irq_chip fake_irq_chip = {
+ .name = "fake",
+ .irq_startup = noop_ret,
+ .irq_shutdown = noop,
+ .irq_enable = noop,
+ .irq_disable = noop,
+ .irq_ack = noop,
+ .irq_mask = noop,
+ .irq_unmask = noop,
+ .irq_set_affinity = noop_affinity,
+ .flags = IRQCHIP_SKIP_SET_WAKE,
+};
+
+static void irq_disable_depth_test(struct kunit *test)
+{
+ struct irq_desc *desc;
+ int virq, ret;
+
+ virq = irq_domain_alloc_descs(-1 /*virq*/, 1 /*nr_irqs*/, 0/*hwirq*/, first_online_node/*node*/, NULL);
+ KUNIT_ASSERT_GE(test, virq, 0);
+
+ irq_set_chip_and_handler(virq, &dummy_irq_chip, handle_simple_irq);
+
+ 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_EXPECT_EQ(test, desc->depth, 0);
+
+ disable_irq(virq);
+ KUNIT_EXPECT_EQ(test, desc->depth, 1);
+
+ enable_irq(virq);
+ KUNIT_EXPECT_EQ(test, desc->depth, 0);
+
+ /* TODO: free virq? */
+}
+
+static void irq_shutdown_depth_test(struct kunit *test)
+{
+ struct irq_desc *desc;
+ int virq, ret;
+
+ virq = irq_domain_alloc_descs(-1 /*virq*/, 1 /*nr_irqs*/, 0/*hwirq*/, first_online_node/*node*/, NULL);
+ KUNIT_ASSERT_GE(test, virq, 0);
+
+ irq_set_chip_and_handler(virq, &dummy_irq_chip, handle_simple_irq);
+
+ 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_EXPECT_EQ(test, desc->depth, 0);
+
+ disable_irq(virq);
+ KUNIT_EXPECT_EQ(test, desc->depth, 1);
+
+ irq_shutdown_and_deactivate(desc);
+ KUNIT_EXPECT_EQ(test, irq_activate_and_startup(desc, IRQ_NORESEND), 0);
+
+ KUNIT_EXPECT_EQ(test, desc->depth, 1);
+
+ enable_irq(virq);
+ KUNIT_EXPECT_EQ(test, desc->depth, 0);
+
+ /* TODO: free virq? */
+}
+
+static void irq_cpuhotplug_test(struct kunit *test)
+{
+ struct irq_desc *desc;
+ struct irq_data *data;
+ int virq, ret;
+ struct irq_affinity_desc affinity = {
+ .is_managed = 1,
+ };
+
+ cpumask_copy(&affinity.mask, cpumask_of(1));
+ KUNIT_ASSERT_PTR_NE(test, get_cpu_device(1), NULL);
+ KUNIT_ASSERT_TRUE(test, cpu_is_hotpluggable(1));
+
+ virq = irq_domain_alloc_descs(-1 /*virq*/, 1 /*nr_irqs*/, 0/*hwirq*/, first_online_node/*node*/, &affinity);
+ KUNIT_ASSERT_GE(test, virq, 0);
+
+ irq_set_chip_and_handler(virq, &fake_irq_chip, handle_simple_irq);
+
+ desc = irq_to_desc(virq);
+ KUNIT_ASSERT_PTR_NE(test, desc, NULL);
+
+ data = irq_desc_get_irq_data(desc);
+ KUNIT_ASSERT_PTR_NE(test, data, NULL);
+
+ ret = request_irq(virq, noop_handler, 0, "test_irq", NULL);
+ KUNIT_EXPECT_EQ(test, ret, 0);
+
+ KUNIT_EXPECT_TRUE(test, irqd_is_activated(data));
+ KUNIT_EXPECT_TRUE(test, irqd_is_started(data));
+ KUNIT_EXPECT_TRUE(test, irqd_affinity_is_managed(data));
+
+ KUNIT_EXPECT_EQ(test, desc->depth, 0);
+
+ disable_irq(virq);
+ KUNIT_EXPECT_EQ(test, desc->depth, 1);
+
+ KUNIT_EXPECT_EQ(test, remove_cpu(1), 0);
+ KUNIT_EXPECT_EQ(test, add_cpu(1), 0);
+
+ KUNIT_EXPECT_EQ(test, desc->depth, 1);
+
+ enable_irq(virq);
+ KUNIT_EXPECT_EQ(test, desc->depth, 0);
+
+ /* TODO: free virq? */
+}
+
+static struct kunit_case irq_test_cases[] = {
+ KUNIT_CASE_SLOW(irq_disable_depth_test),
+ KUNIT_CASE_SLOW(irq_shutdown_depth_test),
+ KUNIT_CASE_SLOW(irq_cpuhotplug_test),
+ {}
+};
+
+static struct kunit_suite irq_test_suite = {
+ .name = "irq_test_cases",
+ .test_cases = irq_test_cases,
+};
+
+kunit_test_suite(irq_test_suite);
+MODULE_DESCRIPTION("IRQ unit test suite");
+MODULE_LICENSE("GPL");
--
2.49.0.1045.g170613ef41-googHi Brian,
kernel test robot noticed the following build warnings:
[auto build test WARNING on tip/irq/core]
[also build test WARNING on linus/master v6.15-rc6 next-20250514]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Brian-Norris/genirq-Add-kunit-tests-for-depth-counts/20250514-065050
base: tip/irq/core
patch link: https://lore.kernel.org/r/20250513224402.864767-2-briannorris%40chromium.org
patch subject: [PATCH 1/2] genirq: Add kunit tests for depth counts
config: alpha-kismet-CONFIG_SMP-CONFIG_IRQ_KUNIT_TEST-0-0 (https://download.01.org/0day-ci/archive/20250515/202505150113.w3vVNU6s-lkp@intel.com/config)
reproduce: (https://download.01.org/0day-ci/archive/20250515/202505150113.w3vVNU6s-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202505150113.w3vVNU6s-lkp@intel.com/
kismet warnings: (new ones prefixed by >>)
>> kismet: WARNING: unmet direct dependencies detected for SMP when selected by IRQ_KUNIT_TEST
WARNING: unmet direct dependencies detected for SMP
Depends on [n]: ALPHA_SABLE [=n] || ALPHA_RAWHIDE [=n] || ALPHA_DP264 [=n] || ALPHA_WILDFIRE [=n] || ALPHA_TITAN [=n] || ALPHA_GENERIC [=n] || ALPHA_SHARK [=n] || ALPHA_MARVEL [=n]
Selected by [y]:
- IRQ_KUNIT_TEST [=y] && KUNIT [=y]
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Hi Brian,
kernel test robot noticed the following build errors:
[auto build test ERROR on tip/irq/core]
[also build test ERROR on linus/master v6.15-rc6 next-20250514]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Brian-Norris/genirq-Add-kunit-tests-for-depth-counts/20250514-065050
base: tip/irq/core
patch link: https://lore.kernel.org/r/20250513224402.864767-2-briannorris%40chromium.org
patch subject: [PATCH 1/2] genirq: Add kunit tests for depth counts
config: arm-randconfig-003-20250514 (https://download.01.org/0day-ci/archive/20250514/202505142327.mfHUg14q-lkp@intel.com/config)
compiler: arm-linux-gnueabi-gcc (GCC) 7.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250514/202505142327.mfHUg14q-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202505142327.mfHUg14q-lkp@intel.com/
All error/warnings (new ones prefixed by >>):
arch/arm/lib/clearbit.S: Assembler messages:
>> arch/arm/lib/clearbit.S:12: Error: architectural extension `mp' is not allowed for the current base architecture
>> arch/arm/lib/clearbit.S:12: Error: selected processor does not support `pldw.w [r1]' in Thumb mode
--
arch/arm/lib/changebit.S: Assembler messages:
>> arch/arm/lib/changebit.S:12: Error: architectural extension `mp' is not allowed for the current base architecture
>> arch/arm/lib/changebit.S:12: Error: selected processor does not support `pldw.w [r1]' in Thumb mode
--
arch/arm/lib/testclearbit.S: Assembler messages:
>> arch/arm/lib/testclearbit.S:12: Error: architectural extension `mp' is not allowed for the current base architecture
>> arch/arm/lib/testclearbit.S:12: Error: selected processor does not support `pldw.w [r1]' in Thumb mode
arch/arm/lib/testclearbit.S:15: Error: architectural extension `mp' is not allowed for the current base architecture
arch/arm/lib/testclearbit.S:15: Error: selected processor does not support `pldw.w [r1]' in Thumb mode
--
arch/arm/lib/testsetbit.S: Assembler messages:
>> arch/arm/lib/testsetbit.S:12: Error: architectural extension `mp' is not allowed for the current base architecture
>> arch/arm/lib/testsetbit.S:12: Error: selected processor does not support `pldw.w [r1]' in Thumb mode
arch/arm/lib/testsetbit.S:15: Error: architectural extension `mp' is not allowed for the current base architecture
arch/arm/lib/testsetbit.S:15: Error: selected processor does not support `pldw.w [r1]' in Thumb mode
--
arch/arm/lib/testchangebit.S: Assembler messages:
>> arch/arm/lib/testchangebit.S:12: Error: architectural extension `mp' is not allowed for the current base architecture
>> arch/arm/lib/testchangebit.S:12: Error: selected processor does not support `pldw.w [r1]' in Thumb mode
arch/arm/lib/testchangebit.S:15: Error: architectural extension `mp' is not allowed for the current base architecture
arch/arm/lib/testchangebit.S:15: Error: selected processor does not support `pldw.w [r1]' in Thumb mode
--
arch/arm/lib/setbit.S: Assembler messages:
>> arch/arm/lib/setbit.S:12: Error: architectural extension `mp' is not allowed for the current base architecture
>> arch/arm/lib/setbit.S:12: Error: selected processor does not support `pldw.w [r1]' in Thumb mode
--
>> arch/arm/kernel/smp.c:98:22: warning: 'get_arch_pgd' defined but not used [-Wunused-function]
static unsigned long get_arch_pgd(pgd_t *pgd)
^~~~~~~~~~~~
/tmp/ccR1vg73.s: Assembler messages:
>> /tmp/ccR1vg73.s:470: Error: architectural extension `mp' is not allowed for the current base architecture
>> /tmp/ccR1vg73.s:471: Error: selected processor does not support `pldw [r1]' in Thumb mode
--
arch/arm/kernel/head-nommu.S: Assembler messages:
>> arch/arm/kernel/head-nommu.S:488: Error: ARM register expected -- `str r0,[,#0x98]'
arch/arm/kernel/head-nommu.S:495: Error: ARM register expected -- `str r0,[,#0x9c]'
>> arch/arm/kernel/head-nommu.S:495: Error: ARM register expected -- `str r5,[,#0xa0]'
arch/arm/kernel/head-nommu.S:497: Error: ARM register expected -- `str r0,[,#0x9c]'
arch/arm/kernel/head-nommu.S:497: Error: ARM register expected -- `str r5,[,#0xa0]'
--
/tmp/ccPRjQyq.s: Assembler messages:
/tmp/ccPRjQyq.s:388: Error: architectural extension `mp' is not allowed for the current base architecture
>> /tmp/ccPRjQyq.s:389: Error: selected processor does not support `pldw [r4]' in Thumb mode
/tmp/ccPRjQyq.s:549: Error: architectural extension `mp' is not allowed for the current base architecture
/tmp/ccPRjQyq.s:550: Error: selected processor does not support `pldw [r4]' in Thumb mode
--
/tmp/cc0opIaH.s: Assembler messages:
/tmp/cc0opIaH.s:1308: Error: architectural extension `mp' is not allowed for the current base architecture
>> /tmp/cc0opIaH.s:1309: Error: selected processor does not support `pldw [r3]' in Thumb mode
/tmp/cc0opIaH.s:2474: Error: architectural extension `mp' is not allowed for the current base architecture
/tmp/cc0opIaH.s:2475: Error: selected processor does not support `pldw [r3]' in Thumb mode
/tmp/cc0opIaH.s:2671: Error: architectural extension `mp' is not allowed for the current base architecture
/tmp/cc0opIaH.s:2672: Error: selected processor does not support `pldw [r3]' in Thumb mode
--
/tmp/ccEJFH9Z.s: Assembler messages:
/tmp/ccEJFH9Z.s:206: Error: architectural extension `mp' is not allowed for the current base architecture
>> /tmp/ccEJFH9Z.s:207: Error: selected processor does not support `pldw [r5]' in Thumb mode
/tmp/ccEJFH9Z.s:233: Error: architectural extension `mp' is not allowed for the current base architecture
/tmp/ccEJFH9Z.s:234: Error: selected processor does not support `pldw [r5]' in Thumb mode
/tmp/ccEJFH9Z.s:540: Error: architectural extension `mp' is not allowed for the current base architecture
>> /tmp/ccEJFH9Z.s:541: Error: selected processor does not support `pldw [r8]' in Thumb mode
/tmp/ccEJFH9Z.s:568: Error: architectural extension `mp' is not allowed for the current base architecture
/tmp/ccEJFH9Z.s:569: Error: selected processor does not support `pldw [r8]' in Thumb mode
..
Kconfig warnings: (for reference only)
WARNING: unmet direct dependencies detected for SMP
Depends on [n]: (CPU_V6K [=n] || CPU_V7 [=n]) && HAVE_SMP [=n] && (MMU [=n] || ARM_MPU [=y])
Selected by [y]:
- IRQ_KUNIT_TEST [=y] && KUNIT [=y]
vim +14 kernel/irq/irq_test.c
13
> 14 static irqreturn_t noop_handler(int, void *)
15 {
16 return IRQ_HANDLED;
17 }
18
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Hi Brian,
kernel test robot noticed the following build warnings:
[auto build test WARNING on tip/irq/core]
[also build test WARNING on linus/master v6.15-rc6 next-20250514]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Brian-Norris/genirq-Add-kunit-tests-for-depth-counts/20250514-065050
base: tip/irq/core
patch link: https://lore.kernel.org/r/20250513224402.864767-2-briannorris%40chromium.org
patch subject: [PATCH 1/2] genirq: Add kunit tests for depth counts
config: arm64-randconfig-001-20250514 (https://download.01.org/0day-ci/archive/20250514/202505142357.R7Xa1KFW-lkp@intel.com/config)
compiler: clang version 17.0.6 (https://github.com/llvm/llvm-project 6009708b4367171ccdbf4b5905cb6a803753fe18)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250514/202505142357.R7Xa1KFW-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202505142357.R7Xa1KFW-lkp@intel.com/
All warnings (new ones prefixed by >>):
>> kernel/irq/irq_test.c:14:36: warning: omitting the parameter name in a function definition is a C2x extension [-Wc2x-extensions]
14 | static irqreturn_t noop_handler(int, void *)
| ^
kernel/irq/irq_test.c:14:44: warning: omitting the parameter name in a function definition is a C2x extension [-Wc2x-extensions]
14 | static irqreturn_t noop_handler(int, void *)
| ^
2 warnings generated.
vim +14 kernel/irq/irq_test.c
13
> 14 static irqreturn_t noop_handler(int, void *)
15 {
16 return IRQ_HANDLED;
17 }
18
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
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