[PATCH 20/25] arm64:ilp32: add sys_ilp32.c and a separate table (in entry.S) to use it

Yury Norov
2016-04-28T22:21:37Z

On Thu, Apr 28, 2016 at 10:43:59PM +0200, Arnd Bergmann wrote:
> On Thursday 28 April 2016 22:19:14 Yury Norov wrote:
> >
> > Yes, we need. Otherwise we have circular dependency like this:
> > arch/arm64/kernel/sys_ilp32.c:60:0: warning: "__SC_WRAP" redefined
> > #define __SC_WRAP(nr, sym) [nr] = compat_##sym,
> > ^
> > In file included from include/asm-generic/unistd.h:1:0,
> > from ./arch/arm64/include/uapi/asm/unistd.h:16,
> > from ./arch/arm64/include/asm/unistd.h:62,
> > from ./include/uapi/linux/unistd.h:7,
> > from include/linux/syscalls.h:23,
> > from arch/arm64/kernel/sys_ilp32.c:30:
> > include/uapi/asm-generic/unistd.h:33:0: note: this is the location of the previous definition
> > #define __SC_WRAP __SYSCALL
> >
> > Defining __SYSCALL_COMPAT at the top of the file does not help much.
>
> Hmm, this sounds like something that we should fix in the asm-generic/unistd.h
> file. Is it just for __SC_WRAP, or also the other macros?
>
> Arnd

For __SYSCALL and __SC_WRAP:

diff --git a/arch/arm64/kernel/sys_ilp32.c
b/arch/arm64/kernel/sys_ilp32.c
index 1458ad7..410d817 100644
--- a/arch/arm64/kernel/sys_ilp32.c
+++ b/arch/arm64/kernel/sys_ilp32.c
@@ -17,6 +17,8 @@
* along with this program. If not, see
* <http://www.gnu.org/licenses/>.
*/

+#define __SYSCALL_COMPAT
+
#include <linux/compiler.h>
#include <linux/errno.h>
#include <linux/fs.h>
@@ -48,13 +50,12 @@ asmlinkage long
ilp32_sys_rt_sigreturn_wrapper(void);

#include <asm/syscall.h>

-#undef __SYSCALL
-#undef __SC_COMP
-#undef __SC_WRAP
-#undef __SC_3264
-#undef __SC_COMP_3264

-#define __SYSCALL_COMPAT
#define __SYSCALL(nr, sym) [nr] = sym,
#define __SC_WRAP(nr, sym) [nr] = compat_##sym,

This patch makes gcc warn about redefinition.

arch/arm64/kernel/sys_ilp32.c:59:0: warning: "__SYSCALL" redefined
#define __SYSCALL(nr, sym) [nr] = sym,
^
In file included from include/asm-generic/unistd.h:1:0,
from ./arch/arm64/include/uapi/asm/unistd.h:16,
from ./arch/arm64/include/asm/unistd.h:62,
from ./include/uapi/linux/unistd.h:7,
from include/linux/syscalls.h:23,
from arch/arm64/kernel/sys_ilp32.c:30:
include/uapi/asm-generic/unistd.h:15:0: note: this is the location of the previous definition
#define __SYSCALL(x, y)
^
arch/arm64/kernel/sys_ilp32.c:60:0: warning: "__SC_WRAP" redefined
#define __SC_WRAP(nr, sym) [nr] = compat_##sym,
^
In file included from include/asm-generic/unistd.h:1:0,
from ./arch/arm64/include/uapi/asm/unistd.h:16,
from ./arch/arm64/include/asm/unistd.h:62,
from ./include/uapi/linux/unistd.h:7,
from include/linux/syscalls.h:23,
from arch/arm64/kernel/sys_ilp32.c:30:
include/uapi/asm-generic/unistd.h:33:0: note: this is the location of the previous definition
#define __SC_WRAP __SYSCALL
^