xen-pciback: fix error return code in pcistub_irq_handler_switch()

Fix to return -ENOENT in the pcistub_device_find() and pci_get_drvdata()
error handling case instead of 0(overwrite to 0 by str_to_slot()), as done
elsewhere in this function.

Acked-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

1 files changed, 7 insertions, 3 deletions

diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c
index 4e8ba38aa0c9..002089918260 100644
--- a/drivers/xen/xen-pciback/pci_stub.c
+++ b/drivers/xen/xen-pciback/pci_stub.c
@@ -1196,19 +1196,23 @@ static ssize_t pcistub_irq_handler_switch(struct device_driver *drv,
         struct pcistub_device *psdev;
         struct xen_pcibk_dev_data *dev_data;
         int domain, bus, slot, func;
-        int err = -ENOENT;
+        int err;
 
         err = str_to_slot(buf, &domain, &bus, &slot, &func);
         if (err)
                 return err;
 
         psdev = pcistub_device_find(domain, bus, slot, func);
-        if (!psdev)
+        if (!psdev) {
+                err = -ENOENT;
                 goto out;
+        }
 
         dev_data = pci_get_drvdata(psdev->dev);
-        if (!dev_data)
+        if (!dev_data) {
+                err = -ENOENT;
                 goto out;
+        }
 
         dev_dbg(&psdev->dev->dev, "%s fake irq handler: %d->%d\n",
                 dev_data->irq_name, dev_data->isr_on,