Re: [PATCH] uio: Fix uio driver to refcount device

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Wed, Mar 11, 2015 at 03:31:42PM +0000, Brian Russell wrote:
> Protect uio driver from crashing if its owner is hot unplugged while there
> are open fds.
> Signed-off-by: Brian Russell <brussell@brocade.com>

Minor nit, you need a blank line before your s-o-b: line.



> ---
>  drivers/uio/uio.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/uio/uio.c b/drivers/uio/uio.c
> index 6276f13..70ce015 100644
> --- a/drivers/uio/uio.c
> +++ b/drivers/uio/uio.c
> @@ -434,9 +434,11 @@ static int uio_open(struct inode *inode, struct file *filep)
>  		goto out;
>  	}
>  
> +	get_device(idev);

What is the real oops caused when a device is removed?  Protecting this
with a reference count seems ok, but it seems "heavy".

thanks,

greg k-h