[PATCH 3/3] misc: pci_endpoint_test: Fix BUG_ON error during pci_disable_msi

From: Kishon Vijay Abraham I
Date: Wed Oct 11 2017 - 04:45:59 EST


pci_disable_msi throws a Kernel BUG if the driver has
successfully requested an irq and not released it. Fix it here by freeing
irqs before invoking pci_disable_msi.

Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
---
drivers/misc/pci_endpoint_test.c | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/drivers/misc/pci_endpoint_test.c b/drivers/misc/pci_endpoint_test.c
index 5cb624b6fa0a..086a7f85c2c0 100644
--- a/drivers/misc/pci_endpoint_test.c
+++ b/drivers/misc/pci_endpoint_test.c
@@ -92,6 +92,7 @@ struct pci_endpoint_test {
void __iomem *bar[6];
struct completion irq_raised;
int last_irq;
+ int num_irqs;
/* mutex to protect the ioctls */
struct mutex mutex;
struct miscdevice miscdev;
@@ -504,6 +505,7 @@ static int pci_endpoint_test_probe(struct pci_dev *pdev,
irq = pci_alloc_irq_vectors(pdev, 1, 32, PCI_IRQ_MSI);
if (irq < 0)
dev_err(dev, "failed to get MSI interrupts\n");
+ test->num_irqs = irq;
}

err = devm_request_irq(dev, pdev->irq, pci_endpoint_test_irqhandler,
@@ -578,6 +580,9 @@ static int pci_endpoint_test_probe(struct pci_dev *pdev,
pci_iounmap(pdev, test->bar[bar]);
}

+ for (i = 0; i < irq; i++)
+ devm_free_irq(dev, pdev->irq + i, test);
+
err_disable_msi:
pci_disable_msi(pdev);
pci_release_regions(pdev);
@@ -591,6 +596,7 @@ static int pci_endpoint_test_probe(struct pci_dev *pdev,
static void pci_endpoint_test_remove(struct pci_dev *pdev)
{
int id;
+ int i;
enum pci_barno bar;
struct pci_endpoint_test *test = pci_get_drvdata(pdev);
struct miscdevice *misc_device = &test->miscdev;
@@ -605,6 +611,8 @@ static void pci_endpoint_test_remove(struct pci_dev *pdev)
if (test->bar[bar])
pci_iounmap(pdev, test->bar[bar]);
}
+ for (i = 0; i < test->num_irqs; i++)
+ devm_free_irq(&pdev->dev, pdev->irq + i, test);
pci_disable_msi(pdev);
pci_release_regions(pdev);
pci_disable_device(pdev);
--
2.11.0