uio: Request/free irq separate from dev lifecycle

[firefly-linux-kernel-4.4.55.git] / drivers / uio / uio.c

diff --git a/drivers/uio/uio.c b/drivers/uio/uio.c
index 6276f13e9e126f8085fdc8949d0d8b784e4df14e..65bf0676d54afc785107822f51a696ae373a2702 100644 (file)
--- a/drivers/uio/uio.c
+++ b/drivers/uio/uio.c
@@ -835,7 +835,15 @@ int __uio_register_device(struct module *owner,
        info->uio_dev = idev;
 
        if (info->irq && (info->irq != UIO_IRQ_CUSTOM)) {
-               ret = devm_request_irq(idev->dev, info->irq, uio_interrupt,
+               /*
+                * Note that we deliberately don't use devm_request_irq
+                * here. The parent module can unregister the UIO device
+                * and call pci_disable_msi, which requires that this
+                * irq has been freed. However, the device may have open
+                * FDs at the time of unregister and therefore may not be
+                * freed until they are released.
+                */
+               ret = request_irq(info->irq, uio_interrupt,
                                  info->irq_flags, info->name, idev);
                if (ret)
                        goto err_request_irq;
@@ -871,6 +879,8 @@ void uio_unregister_device(struct uio_info *info)
 
        uio_dev_del_attributes(idev);
 
+       free_irq(idev->info->irq, idev);
+
        device_destroy(&uio_class, MKDEV(uio_major, idev->minor));
 
        return;