Bug 59041

from: Steve Russo <svrusso1@gmail.com>

Compiling iwlwifi or alx against 3.4.47 kernel gives redefinition error. Tried using compat-drivers-3.9-rc4-2-su,  compat-drivers-3.9-rc2-2-su, and compat-drivers-3.8.3-2-snpu. Does not work from any of them.

Patch against compat-drivers-3.9-rc4-2-su follows body.

Error:
auser@mycomputer:/path/to/home/Dev/Wired/compat-drivers-3.9-rc4-2-su# make
make -C /lib/modules/3.4.47/build M=/path/to/home/Dev/Wired/compat-drivers-3.9-rc4-2-su modules
make[1]: Entering directory `/path/to/home/Dev/Kernel/generic/linux-3.4.47'
  CC [M]  /path/to/home/Dev/Wired/compat-drivers-3.9-rc4-2-su/compat/main.o
In file included from /path/to/home/Dev/Wired/compat-drivers-3.9-rc4-2-su/include/linux/compat-2.6.h:71:0,
                 from <command-line>:0:
/path/to/home/Dev/Wired/compat-drivers-3.9-rc4-2-su/include/linux/compat-3.8.h:49:32: error: redefinition of ‘kref_get_unless_zero’
In file included from include/linux/kobject.h:24:0,
                 from include/linux/device.h:17,
                 from include/linux/dmaengine.h:24,
                 from include/linux/skbuff.h:31,
                 from include/linux/if_ether.h:134,
                 from include/linux/netdevice.h:29,
                 from /path/to/home/Dev/Wired/compat-drivers-3.9-rc4-2-su/include/linux/compat-2.6.29.h:5,
                 from /path/to/home/Dev/Wired/compat-drivers-3.9-rc4-2-su/include/linux/compat-2.6.h:52,
                 from <command-line>:0:
include/linux/kref.h:113:32: note: previous definition of ‘kref_get_unless_zero’ was here
make[3]: *** [/path/to/home/Dev/Wired/compat-drivers-3.9-rc4-2-su/compat/main.o] Error 1
make[2]: *** [/path/to/home/Dev/Wired/compat-drivers-3.9-rc4-2-su/compat] Error 2
make[1]: *** [_module_/path/to/home/Dev/Wired/compat-drivers-3.9-rc4-2-su] Error 2
make[1]: Leaving directory `/path/to/home/Dev/Kernel/generic/linux-3.4.47'
make: *** [modules] Error 2
auser@mycomputer:/path/to/home/Dev/Wired/compat-drivers-3.9-rc4-2-su#

Signed-off-by: Steve Russo <svrusso1@gmail.com>
---

The following patch against compat-drivers-3.9-rc4-2-su allowed compilation to complete.

--- compat-3.8.h.0	2013-05-30 15:57:51.333132738 -0400
+++ compat-3.8.h	2013-05-30 15:59:12.689517900 -0400
@@ -22,6 +22,7 @@ extern void netdev_set_default_ethtool_o
 
 extern bool hid_ignore(struct hid_device *);
 
+#ifndef _KREF_H_
 /* This backports:
  *
  * commit 4b20db3de8dab005b07c74161cb041db8c5ff3a7
@@ -50,6 +51,7 @@ static inline int __must_check kref_get_
 {
 	return atomic_add_unless(&kref->refcount, 1, 0);
 }
+#endif
 
 /* This backports:
  *