improve sys_newuname() for compat architectures

On an architecture that supports 32-bit compat we need to override the
reported machine in uname with the 32-bit value.  Instead of doing this
separately in every architecture introduce a COMPAT_UTS_MACHINE define in
<asm/compat.h> and apply it directly in sys_newuname().

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 3 insertions, 5 deletions

diff --git a/arch/x86/include/asm/compat.h b/arch/x86/include/asm/compat.h
index 9a9c7bdc923d..306160e58b48 100644
--- a/arch/x86/include/asm/compat.h
+++ b/arch/x86/include/asm/compat.h
@@ -8,7 +8,8 @@
 #include <linux/sched.h>
 #include <asm/user32.h>
 
-#define COMPAT_USER_HZ  100
+#define COMPAT_USER_HZ          100
+#define COMPAT_UTS_MACHINE      "i686\0\0"
 
 typedef u32             compat_size_t;
 typedef s32             compat_ssize_t;
diff --git a/arch/x86/include/asm/syscalls.h b/arch/x86/include/asm/syscalls.h
index 50f6a569f0d1..47cd606c3537 100644
--- a/arch/x86/include/asm/syscalls.h
+++ b/arch/x86/include/asm/syscalls.h
@@ -68,11 +68,8 @@ int sys_vm86(unsigned long, unsigned long, struct pt_regs *);
 long sys_arch_prctl(int, unsigned long);
 
 /* kernel/sys_x86_64.c */
-struct new_utsname;
-
 asmlinkage long sys_mmap(unsigned long, unsigned long, unsigned long,
                          unsigned long, unsigned long, unsigned long);
-asmlinkage long sys_uname(struct new_utsname __user *);
 
 #endif /* CONFIG_X86_32 */
 #endif /* _ASM_X86_SYSCALLS_H */
diff --git a/arch/x86/include/asm/unistd_64.h b/arch/x86/include/asm/unistd_64.h
index 4843f7ba754a..83e2d6dc5038 100644
--- a/arch/x86/include/asm/unistd_64.h
+++ b/arch/x86/include/asm/unistd_64.h
@@ -146,7 +146,7 @@ __SYSCALL(__NR_wait4, sys_wait4)
 #define __NR_kill                               62
 __SYSCALL(__NR_kill, sys_kill)
 #define __NR_uname                              63
-__SYSCALL(__NR_uname, sys_uname)
+__SYSCALL(__NR_uname, sys_newuname)
 
 #define __NR_semget                             64
 __SYSCALL(__NR_semget, sys_semget)