Re: [PATCH 1/3] tools/virtio: fix READ_ONCE()

From: Jason Wang
Date: Thu Nov 24 2016 - 21:39:15 EST




On 2016å11æ24æ 18:25, Mark Rutland wrote:
The virtio tools implementation of READ_ONCE() has a single parameter called
'var', but erroneously refers to 'val' for its cast, and thus won't work unless
there's a variable of the correct type that happens to be called 'var'.

Fix this with s/var/val/, making READ_ONCE() work as expected regardless.

Fixes: a7c490333df3cff5 ("tools/virtio: use virt_xxx barriers")
Signed-off-by: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Jason Wang <jasowang@xxxxxxxxxx>
Cc: Michael S. Tsirkin <mst@xxxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx
---
tools/virtio/linux/compiler.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/virtio/linux/compiler.h b/tools/virtio/linux/compiler.h
index 845960e..c9ccfd4 100644
--- a/tools/virtio/linux/compiler.h
+++ b/tools/virtio/linux/compiler.h
@@ -4,6 +4,6 @@
#define WRITE_ONCE(var, val) \
(*((volatile typeof(val) *)(&(var))) = (val))
-#define READ_ONCE(var) (*((volatile typeof(val) *)(&(var))))
+#define READ_ONCE(var) (*((volatile typeof(var) *)(&(var))))
#endif

Reviewed-by: Jason Wang <jasowang@xxxxxxxxxx>