[PATCH] af_packet: fix sparse warning

[PATCH] af_packet: fix sparse warning

[Michael S. Tsirkin]

af_packet produces lots of these:
	net/packet/af_packet.c:384:39: warning: incorrect type in return expression (different modifiers)
	net/packet/af_packet.c:384:39:    expected struct page [pure] *
	net/packet/af_packet.c:384:39:    got struct page *

this seems to be because sparse does not realize that _pure
refers to function, not the returned pointer.

Tweak code slightly to avoid the warning.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 net/packet/af_packet.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index d4a877e..586229a 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -378,7 +378,7 @@ static void unregister_prot_hook(struct sock *sk, bool sync)
 		__unregister_prot_hook(sk, sync);
 }
 
-static inline __pure struct page *pgv_to_page(void *addr)
+static inline struct page * __pure pgv_to_page(void *addr)
 {
 	if (is_vmalloc_addr(addr))
 		return vmalloc_to_page(addr);
-- 
MST

Re: [PATCH] af_packet: fix sparse warning

[David Miller]

From: "Michael S. Tsirkin" <mst@redhat.com>
Date: Mon, 24 Nov 2014 13:32:16 +0200

> af_packet produces lots of these:
> 	net/packet/af_packet.c:384:39: warning: incorrect type in return expression (different modifiers)
> 	net/packet/af_packet.c:384:39:    expected struct page [pure] *
> 	net/packet/af_packet.c:384:39:    got struct page *
> 
> this seems to be because sparse does not realize that _pure
> refers to function, not the returned pointer.
> 
> Tweak code slightly to avoid the warning.
> 
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Applied, please report the sparse bug if you haven't already.

Thanks.