[RFC v2 3/5] vfio-ccw: Set pa_nr to 0 if memory allocation fails for pa_iova_pfn

Farhan Ali
2019-07-08T20:10:48Z

So we don't call try to call vfio_unpin_pages() incorrectly.

Fixes: 0a19e61e6d4c ("vfio: ccw: introduce channel program interfaces")
Signed-off-by: Farhan Ali <alifm@linux.ibm.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
---
drivers/s390/cio/vfio_ccw_cp.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/s390/cio/vfio_ccw_cp.c b/drivers/s390/cio/vfio_ccw_cp.c
index 31a04a5..1b93863 100644
--- a/drivers/s390/cio/vfio_ccw_cp.c
+++ b/drivers/s390/cio/vfio_ccw_cp.c
@@ -72,8 +72,10 @@ static int pfn_array_alloc(struct pfn_array *pa, u64 iova, unsigned int len)
sizeof(*pa->pa_iova_pfn) +
sizeof(*pa->pa_pfn),
GFP_KERNEL);
- if (unlikely(!pa->pa_iova_pfn))
+ if (unlikely(!pa->pa_iova_pfn)) {
+ pa->pa_nr = 0;
return -ENOMEM;
+ }
pa->pa_pfn = pa->pa_iova_pfn + pa->pa_nr;

pa->pa_iova_pfn[0] = pa->pa_iova >> PAGE_SHIFT;
--
2.7.4