Re: [PATCH 2/3] hw/virtio: Remove NULL check in virtio_free_region_cache()

[Stefano Garzarella]

On Thu, Aug 26, 2021 at 07:26:57PM +0200, Philippe Mathieu-Daudé wrote:

virtio_free_region_cache() is called within call_rcu(),
always with a non-NULL argument. Ensure new code keep it
that way by replacing the NULL check by an assertion.
Add a comment this function is called within call_rcu().

Signed-off-by: Philippe Mathieu-Daudé <phi...@redhat.com>
---
hw/virtio/virtio.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index a5214bca612..3a1f6c520cb 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -133,12 +133,10 @@ struct VirtQueue
    QLIST_ENTRY(VirtQueue) node;
};

+/* Called within call_rcu().  */
static void virtio_free_region_cache(VRingMemoryRegionCaches *caches)
{
-    if (!caches) {
-        return;
-    }
-
+    assert(caches != NULL);
    address_space_cache_destroy(&caches->desc);
    address_space_cache_destroy(&caches->avail);
    address_space_cache_destroy(&caches->used);
--
2.31.1

Reviewed-by: Stefano Garzarella <sgarz...@redhat.com>