From: Philippe Mathieu-Daudé <philmd@redhat.com>
Date: Thu, 26 Aug 2021 17:26:57 +0000 (+0200)
Subject: hw/virtio: Remove NULL check in virtio_free_region_cache()
X-Git-Tag: v6.2.0-rc0~116^2~14
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=b116d6c319661b59d0461f771f407e47f54a8c80;p=users%2Fdwmw2%2Fqemu.git

hw/virtio: Remove NULL check in virtio_free_region_cache()

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 <philmd@redhat.com>
Message-Id: <20210826172658.2116840-3-philmd@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
---

diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index a5214bca61..3a1f6c520c 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);