From: "Jason J. Herne" jjherne@linux.vnet.ibm.com
[ Upstream commit 408358b50deaf59b07c82a7bff8c7e7cce031fae ]
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 Signed-off-by: Sasha Levin alexander.levin@verizon.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 f20b4d66c75f..4a39b54732d0 100644 --- a/drivers/s390/cio/vfio_ccw_cp.c +++ b/drivers/s390/cio/vfio_ccw_cp.c @@ -330,6 +330,8 @@ 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;