[PATCH AUTOSEL 5.4 041/175] pmu/smmuv3: Clear IRQ affinity hint on device removal

Sasha Levin
2020-06-09T00:12:42Z

From: Jean-Philippe Brucker <jean-philippe@linaro.org>

[ Upstream commit 10f6cd2af21bb44faab31a50ec3361d7649e5a39 ]

Currently when trying to remove the SMMUv3 PMU module we get a
WARN_ON_ONCE from free_irq(), because the affinity hint set during probe
hasn't been properly cleared.

[ 238.878383] WARNING: CPU: 0 PID: 175 at kernel/irq/manage.c:1744 free_irq+0x324/0x358
...
[ 238.897263] Call trace:
[ 238.897998] free_irq+0x324/0x358
[ 238.898792] devm_irq_release+0x18/0x28
[ 238.899189] release_nodes+0x1b0/0x228
[ 238.899984] devres_release_all+0x38/0x60
[ 238.900779] device_release_driver_internal+0x10c/0x1d0
[ 238.901574] driver_detach+0x50/0xe0
[ 238.902368] bus_remove_driver+0x5c/0xd8
[ 238.903448] driver_unregister+0x30/0x60
[ 238.903958] platform_driver_unregister+0x14/0x20
[ 238.905075] arm_smmu_pmu_exit+0x1c/0xecc [arm_smmuv3_pmu]
[ 238.905547] __arm64_sys_delete_module+0x14c/0x260
[ 238.906342] el0_svc_common.constprop.0+0x74/0x178
[ 238.907355] do_el0_svc+0x24/0x90
[ 238.907932] el0_sync_handler+0x11c/0x198
[ 238.908979] el0_sync+0x158/0x180

Just like the other perf drivers, clear the affinity hint before
releasing the device.

Fixes: 7d839b4b9e00 ("perf/smmuv3: Add arm64 smmuv3 pmu driver")
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Link: https://lore.kernel.org/r/20200422084805.237738-1-jean-philippe@linaro.org
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/perf/arm_smmuv3_pmu.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/perf/arm_smmuv3_pmu.c b/drivers/perf/arm_smmuv3_pmu.c
index 2f8787276d9b..3269232ff570 100644
--- a/drivers/perf/arm_smmuv3_pmu.c
+++ b/drivers/perf/arm_smmuv3_pmu.c
@@ -815,7 +815,7 @@ static int smmu_pmu_probe(struct platform_device *pdev)
if (err) {
dev_err(dev, "Error %d registering hotplug, PMU @%pa\n",
err, &res_0->start);
- return err;
+ goto out_clear_affinity;
}

err = perf_pmu_register(&smmu_pmu->pmu, name, -1);
@@ -834,6 +834,8 @@ static int smmu_pmu_probe(struct platform_device *pdev)

out_unregister:
cpuhp_state_remove_instance_nocalls(cpuhp_state_num, &smmu_pmu->node);
+out_clear_affinity:
+ irq_set_affinity_hint(smmu_pmu->irq, NULL);
return err;
}

@@ -843,6 +845,7 @@ static int smmu_pmu_remove(struct platform_device *pdev)

perf_pmu_unregister(&smmu_pmu->pmu);
cpuhp_state_remove_instance_nocalls(cpuhp_state_num, &smmu_pmu->node);
+ irq_set_affinity_hint(smmu_pmu->irq, NULL);

return 0;
}
--
2.25.1