Linux Virtualization - Feb 2020 - [PATCH] virtio_balloon: Fix unused label warning

From: Borislav Petkov <bp at suse.de>

Fix

  drivers/virtio/virtio_balloon.c: In function ?virtballoon_probe?:
  drivers/virtio/virtio_balloon.c:963:1: warning: label ?out_del_vqs? defined
but not used [-Wunused-label]
    963 | out_del_vqs:
        | ^~

The CONFIG_BALLOON_COMPACTION ifdeffery should enclose it too.

Signed-off-by: Borislav Petkov <bp at suse.de>
Cc: David Hildenbrand <david at redhat.com>
---
 drivers/virtio/virtio_balloon.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index 7bfe365d9372..b6ed5f8bccb1 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -959,9 +959,9 @@ static int virtballoon_probe(struct virtio_device *vdev)
 	iput(vb->vb_dev_info.inode);
 out_kern_unmount:
 	kern_unmount(balloon_mnt);
-#endif
 out_del_vqs:
 	vdev->config->del_vqs(vdev);
+#endif
 out_free_vb:
 	kfree(vb);
 out:
-- 
2.21.0

On 10.02.20 10:33, Borislav Petkov wrote:
> From: Borislav Petkov <bp at suse.de>
> 
> Fix
> 
>   drivers/virtio/virtio_balloon.c: In function ?virtballoon_probe?:
>   drivers/virtio/virtio_balloon.c:963:1: warning: label ?out_del_vqs?
defined but not used [-Wunused-label]
>     963 | out_del_vqs:
>         | ^~
> 
> The CONFIG_BALLOON_COMPACTION ifdeffery should enclose it too.
> 
> Signed-off-by: Borislav Petkov <bp at suse.de>
> Cc: David Hildenbrand <david at redhat.com>
> ---
>  drivers/virtio/virtio_balloon.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/virtio/virtio_balloon.c
b/drivers/virtio/virtio_balloon.c
> index 7bfe365d9372..b6ed5f8bccb1 100644
> --- a/drivers/virtio/virtio_balloon.c
> +++ b/drivers/virtio/virtio_balloon.c
> @@ -959,9 +959,9 @@ static int virtballoon_probe(struct virtio_device
*vdev)
>  	iput(vb->vb_dev_info.inode);
>  out_kern_unmount:
>  	kern_unmount(balloon_mnt);
> -#endif
>  out_del_vqs:
>  	vdev->config->del_vqs(vdev);
> +#endif
>  out_free_vb:
>  	kfree(vb);
>  out:
> 
Oh, right, thanks!

Reviewed-by: David Hildenbrand <david at redhat.com>

-- 
Thanks,

David / dhildenb

On Mon, Feb 10, 2020 at 10:33:28AM +0100, Borislav Petkov
wrote:
> From: Borislav Petkov <bp at suse.de>
> 
> Fix
> 
>   drivers/virtio/virtio_balloon.c: In function ?virtballoon_probe?:
>   drivers/virtio/virtio_balloon.c:963:1: warning: label ?out_del_vqs?
defined but not used [-Wunused-label]
>     963 | out_del_vqs:
>         | ^~
> 
> The CONFIG_BALLOON_COMPACTION ifdeffery should enclose it too.
> 
> Signed-off-by: Borislav Petkov <bp at suse.de>
> Cc: David Hildenbrand <david at redhat.com>
> ---
>  drivers/virtio/virtio_balloon.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/virtio/virtio_balloon.c
b/drivers/virtio/virtio_balloon.c
> index 7bfe365d9372..b6ed5f8bccb1 100644
> --- a/drivers/virtio/virtio_balloon.c
> +++ b/drivers/virtio/virtio_balloon.c
> @@ -959,9 +959,9 @@ static int virtballoon_probe(struct virtio_device
*vdev)
>  	iput(vb->vb_dev_info.inode);
>  out_kern_unmount:
>  	kern_unmount(balloon_mnt);
> -#endif
>  out_del_vqs:
>  	vdev->config->del_vqs(vdev);
> +#endif
I noticed the same issue and sent an almost identical patch [1] but I
kept the call to del_vqs outside of the CONFIG_BALLOON_COMPACTION guard
since it seems like that should still be called when that config is
unset, as that was the case before commit 1ad6f58ea936 ("virtio_balloon:
Fix memory leaks on errors in virtballoon_probe()"). Is this patch fully
correct? I am not a virtio expert at all, just noticing from a brief
reading of this function.

[1]: https://lore.kernel.org/lkml/20200216004039.23464-1-natechancellor at
gmail.com/

Cheers,
Nathan
>  out_free_vb:
>  	kfree(vb);
>  out:
> -- 
> 2.21.0
>

> Am 16.02.2020 um 08:46 schrieb Nathan Chancellor <natechancellor at
gmail.com>:
> 
> ?On Mon, Feb 10, 2020 at 10:33:28AM +0100, Borislav Petkov wrote:
>> From: Borislav Petkov <bp at suse.de>
>> 
>> Fix
>> 
>>  drivers/virtio/virtio_balloon.c: In function ?virtballoon_probe?:
>>  drivers/virtio/virtio_balloon.c:963:1: warning: label ?out_del_vqs?
defined but not used [-Wunused-label]
>>    963 | out_del_vqs:
>>        | ^~
>> 
>> The CONFIG_BALLOON_COMPACTION ifdeffery should enclose it too.
>> 
>> Signed-off-by: Borislav Petkov <bp at suse.de>
>> Cc: David Hildenbrand <david at redhat.com>
>> ---
>> drivers/virtio/virtio_balloon.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>> 
>> diff --git a/drivers/virtio/virtio_balloon.c
b/drivers/virtio/virtio_balloon.c
>> index 7bfe365d9372..b6ed5f8bccb1 100644
>> --- a/drivers/virtio/virtio_balloon.c
>> +++ b/drivers/virtio/virtio_balloon.c
>> @@ -959,9 +959,9 @@ static int virtballoon_probe(struct virtio_device
*vdev)
>>    iput(vb->vb_dev_info.inode);
>> out_kern_unmount:
>>    kern_unmount(balloon_mnt);
>> -#endif
>> out_del_vqs:
>>    vdev->config->del_vqs(vdev);
>> +#endif
> 
> I noticed the same issue and sent an almost identical patch [1] but I
> kept the call to del_vqs outside of the CONFIG_BALLOON_COMPACTION guard
> since it seems like that should still be called when that config is
> unset, as that was the case before commit 1ad6f58ea936
("virtio_balloon:
> Fix memory leaks on errors in virtballoon_probe()"). Is this patch
fully
> correct? I am not a virtio expert at all, just noticing from a brief
> reading of this function.
I think you are right and this splipped my eyes!