Patch "um: virt-pci: properly remove PCI device from bus" has been added to the 5.15-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    um: virt-pci: properly remove PCI device from bus

to the 5.15-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     um-virt-pci-properly-remove-pci-device-from-bus.patch
and it can be found in the queue-5.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit e69b3aa604b36346acc9a1720729ba1eaedbd75b
Author: Benjamin Berg <benjamin.berg@xxxxxxxxx>
Date:   Thu Feb 9 10:00:05 2023 +0100

    um: virt-pci: properly remove PCI device from bus
    
    [ Upstream commit 339b84dcd7113dd076419ea2a47128cc53450305 ]
    
    Triggering a bus rescan will not cause the PCI device to be removed. It
    is required to explicitly stop and remove the device from the bus.
    
    Fixes: 68f5d3f3b654 ("um: add PCI over virtio emulation driver")
    Signed-off-by: Benjamin Berg <benjamin.berg@xxxxxxxxx>
    Signed-off-by: Richard Weinberger <richard@xxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/arch/um/drivers/virt-pci.c b/arch/um/drivers/virt-pci.c
index 2829347d1e906..d762d726b66cf 100644
--- a/arch/um/drivers/virt-pci.c
+++ b/arch/um/drivers/virt-pci.c
@@ -618,22 +618,33 @@ static void um_pci_virtio_remove(struct virtio_device *vdev)
 	struct um_pci_device *dev = vdev->priv;
 	int i;
 
-        /* Stop all virtqueues */
-        vdev->config->reset(vdev);
-        vdev->config->del_vqs(vdev);
-
 	device_set_wakeup_enable(&vdev->dev, false);
 
 	mutex_lock(&um_pci_mtx);
 	for (i = 0; i < MAX_DEVICES; i++) {
 		if (um_pci_devices[i].dev != dev)
 			continue;
+
 		um_pci_devices[i].dev = NULL;
 		irq_free_desc(dev->irq);
+
+		break;
 	}
 	mutex_unlock(&um_pci_mtx);
 
-	um_pci_rescan();
+	if (i < MAX_DEVICES) {
+		struct pci_dev *pci_dev;
+
+		pci_dev = pci_get_slot(bridge->bus, i);
+		if (pci_dev)
+			pci_stop_and_remove_bus_device_locked(pci_dev);
+	}
+
+	/* Stop all virtqueues */
+	virtio_reset_device(vdev);
+	dev->cmd_vq = NULL;
+	dev->irq_vq = NULL;
+	vdev->config->del_vqs(vdev);
 
 	kfree(dev);
 }