[PULL 0/1] vfio-ccw: bugfix

[PULL 0/1] vfio-ccw: bugfix

[Cornelia Huck]

The following changes since commit 978fa72e82e375764e6e31e7a721408c5186918f:

  s390: remove named saved segment support (2017-11-08 09:47:54 +0100)

are available in the git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/vfio-ccw.git tags/vfio-ccw-20171109

for you to fetch changes up to 408358b50deaf59b07c82a7bff8c7e7cce031fae:

  s390: vfio-ccw: Do not attempt to free no-op, test and tic cda. (2017-11-08 14:39:53 +0100)

----------------------------------------------------------------
A vfio-ccw bugfix: avoid freeing that which should not be freed.

----------------------------------------------------------------

Jason J. Herne (1):
  s390: vfio-ccw: Do not attempt to free no-op, test and tic cda.

 drivers/s390/cio/vfio_ccw_cp.c | 2 ++
 1 file changed, 2 insertions(+)

-- 
2.13.6

[PULL 1/1] s390: vfio-ccw: Do not attempt to free no-op, test and tic cda.

[Cornelia Huck]

From: "Jason J. Herne" <jjherne@linux.vnet.ibm.com>

Because we do not make use of the cda (channel data address) for test,
no-op ccws no address translation takes place. This means cda could
contain a guest address which we do not want to attempt to free. Let's
check the command type and skip cda free when it is not needed.

For a TIC ccw, ccw->cda points to either a ccw in an existing chain or
it points to a whole new allocated chain. In either case the data will
be freed when the owning chain is freed.

Signed-off-by: Jason J. Herne <jjherne@linux.vnet.ibm.com>
Reviewed-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
Message-Id: <1510068152-21988-1-git-send-email-jjherne@linux.vnet.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
---
 drivers/s390/cio/vfio_ccw_cp.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/s390/cio/vfio_ccw_cp.c b/drivers/s390/cio/vfio_ccw_cp.c
index d8f98ad9b029..7ebbd8b482f5 100644
--- a/drivers/s390/cio/vfio_ccw_cp.c
+++ b/drivers/s390/cio/vfio_ccw_cp.c
@@ -332,6 +332,8 @@ static void ccwchain_cda_free(struct ccwchain *chain, int idx)
 {
 	struct ccw1 *ccw = chain->ch_ccw + idx;
 
+	if (ccw_is_test(ccw) || ccw_is_noop(ccw) || ccw_is_tic(ccw))
+		return;
 	if (!ccw->count)
 		return;
 
-- 
2.13.6

Re: [PULL 0/1] vfio-ccw: bugfix

[Heiko Carstens]

On Thu, Nov 09, 2017 at 05:21:19PM +0100, Cornelia Huck wrote:
> The following changes since commit 978fa72e82e375764e6e31e7a721408c5186918f:
> 
>   s390: remove named saved segment support (2017-11-08 09:47:54 +0100)
> 
> are available in the git repository at:
> 
>   git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/vfio-ccw.git tags/vfio-ccw-20171109
> 
> for you to fetch changes up to 408358b50deaf59b07c82a7bff8c7e7cce031fae:
> 
>   s390: vfio-ccw: Do not attempt to free no-op, test and tic cda. (2017-11-08 14:39:53 +0100)
> 
> ----------------------------------------------------------------
> A vfio-ccw bugfix: avoid freeing that which should not be freed.
> 
> ----------------------------------------------------------------
> 
> Jason J. Herne (1):
>   s390: vfio-ccw: Do not attempt to free no-op, test and tic cda.

Pulled into features branch. Thanks!