Re: [PATCH v2] s390/vfio-ap: fix memory leak in mdev remove callback

Tony Krowiak
2021-05-13T14:20:51Z

On 5/12/21 11:32 AM, Christian Borntraeger wrote:
>
>
> On 12.05.21 14:41, Jason Gunthorpe wrote:
>> On Mon, May 10, 2021 at 05:48:37PM -0400, Tony Krowiak wrote:
>>> The mdev remove callback for the vfio_ap device driver bails out with
>>> -EBUSY if the mdev is in use by a KVM guest. The intended purpose was
>>> to prevent the mdev from being removed while in use; however,
>>> returning a
>>> non-zero rc does not prevent removal. This could result in a memory
>>> leak
>>> of the resources allocated when the mdev was created. In addition, the
>>> KVM guest will still have access to the AP devices assigned to the mdev
>>> even though the mdev no longer exists.
>>>
>>> To prevent this scenario, cleanup will be done - including
>>> unplugging the
>>> AP adapters, domains and control domains - regardless of whether the
>>> mdev
>>> is in use by a KVM guest or not.
>>>
>>> Fixes: 258287c994de ("s390: vfio-ap: implement mediated device open
>>> callback")
>>> Cc: stable@vger.kernel.org
>>> Signed-off-by: Tony Krowiak <akrowiak@stny.rr.com>
>>> ---
>>>   drivers/s390/crypto/vfio_ap_ops.c | 13 ++-----------
>>>   1 file changed, 2 insertions(+), 11 deletions(-)
>>
>> Can you please ensure this goes to a -rc branch or through Alex's
>> tree?
>
> So you want this is 5.13-rc?
> I can apply this to the s390 tree if that is ok.

If it is in time for 5.13.-rc, then yes, go ahead and
apply it.