As device_create_file() can return error number,
it should be better to check the return value and
deal with the exception.

Fixes: 0ba002bc4393 ("virt: Add vboxguest driver for Virtual Box Guest integration")
Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
---
 drivers/virt/vboxguest/vboxguest_linux.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/virt/vboxguest/vboxguest_linux.c b/drivers/virt/vboxguest/vboxguest_linux.c
index 4ccfd30c2a30..0fee8e6ee6e0 100644
--- a/drivers/virt/vboxguest/vboxguest_linux.c
+++ b/drivers/virt/vboxguest/vboxguest_linux.c
@@ -390,8 +390,13 @@ static int vbg_pci_probe(struct pci_dev *pci, const struct pci_device_id *id)
 	}
 
 	pci_set_drvdata(pci, gdev);
-	device_create_file(dev, &dev_attr_host_version);
-	device_create_file(dev, &dev_attr_host_features);
+
+	ret = device_create_file(dev, &dev_attr_host_version);
+	if (ret)
+		goto err_unregister_misc_device_user;
+	ret = device_create_file(dev, &dev_attr_host_features);
+	if (ret)
+		goto err_unregister_misc_device_user;
 
 	vbg_info("vboxguest: misc device minor %d, IRQ %d, I/O port %x, MMIO at %pap (size %pap)\n",
 		 gdev->misc_device.minor, pci->irq, gdev->io_port,
-- 
2.25.1

On Thu, Sep 01, 2022 at 03:45:21PM +0800, Jiasheng Jiang wrote:
> As device_create_file() can return error number,
> it should be better to check the return value and
> deal with the exception.
> 
> Fixes: 0ba002bc4393 ("virt: Add vboxguest driver for Virtual Box Guest integration")
> Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
> ---
>  drivers/virt/vboxguest/vboxguest_linux.c | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/virt/vboxguest/vboxguest_linux.c b/drivers/virt/vboxguest/vboxguest_linux.c
> index 4ccfd30c2a30..0fee8e6ee6e0 100644
> --- a/drivers/virt/vboxguest/vboxguest_linux.c
> +++ b/drivers/virt/vboxguest/vboxguest_linux.c
> @@ -390,8 +390,13 @@ static int vbg_pci_probe(struct pci_dev *pci, const struct pci_device_id *id)
>  	}
>  
>  	pci_set_drvdata(pci, gdev);
> -	device_create_file(dev, &dev_attr_host_version);
> -	device_create_file(dev, &dev_attr_host_features);
> +
> +	ret = device_create_file(dev, &dev_attr_host_version);
> +	if (ret)
> +		goto err_unregister_misc_device_user;
> +	ret = device_create_file(dev, &dev_attr_host_features);
> +	if (ret)
> +		goto err_unregister_misc_device_user;

No, this driver should be using an attribute group, please switch it to
use that instead.

>  	vbg_info("vboxguest: misc device minor %d, IRQ %d, I/O port %x, MMIO at %pap (size %pap)\n",
>  		 gdev->misc_device.minor, pci->irq, gdev->io_port,

This should also be removed, when drivers are working properly, they are
quiet.  But that can be a second patch in your series.

thanks,

greg k-h

On Thu, Sep 01, 2022 at 03:45:21PM +0800, Jiasheng Jiang wrote:
> As device_create_file() can return error number,
> it should be better to check the return value and
> deal with the exception.
> 
> Fixes: 0ba002bc4393 ("virt: Add vboxguest driver for Virtual Box Guest integration")
> Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
> ---
>  drivers/virt/vboxguest/vboxguest_linux.c | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/virt/vboxguest/vboxguest_linux.c b/drivers/virt/vboxguest/vboxguest_linux.c
> index 4ccfd30c2a30..0fee8e6ee6e0 100644
> --- a/drivers/virt/vboxguest/vboxguest_linux.c
> +++ b/drivers/virt/vboxguest/vboxguest_linux.c
> @@ -390,8 +390,13 @@ static int vbg_pci_probe(struct pci_dev *pci, const struct pci_device_id *id)
>  	}
>  
>  	pci_set_drvdata(pci, gdev);
> -	device_create_file(dev, &dev_attr_host_version);
> -	device_create_file(dev, &dev_attr_host_features);
> +
> +	ret = device_create_file(dev, &dev_attr_host_version);
> +	if (ret)
> +		goto err_unregister_misc_device_user;
> +	ret = device_create_file(dev, &dev_attr_host_features);
> +	if (ret)
> +		goto err_unregister_misc_device_user;

This is also buggy, please always test your changes before sending them
out :(