[PATCH] x86_64: Fix 32bit aio setup

Kernel 2.6.9-rc3-mm3 has a bug in function sys32_io_setup in file
arch/x86_64/ia32/sys_ia32.c.  Local variable ctx64 is not initiated before
sys32_io_setup calls sys_io_setup.  If ctx64 is not zero, and sys_io_setup
will return -EINVAL.  Generic function compat_sys_io_setup has not the bug.

Here is the patch against 2.6.9-rc3-mm3. Just use compat_sys_io_setup to
replace sys32_io_setup.
Signed-off-by: Zhang Yanmin <yanmin.zhang@intel.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/x86_64/ia32/ia32entry.S

@@ -547,7 +547,7 @@ ia32_sys_call_table:
 	.quad compat_sys_sched_getaffinity
 	.quad sys32_set_thread_area
 	.quad sys32_get_thread_area
-	.quad sys32_io_setup		/* 245 */
+	.quad compat_sys_io_setup	/* 245 */
 	.quad sys_io_destroy
 	.quad sys32_io_getevents
 	.quad sys32_io_submit

arch/x86_64/ia32/sys_ia32.c

@@ -1186,21 +1186,6 @@ long sys32_kill(int pid, int sig)
 	return sys_kill(pid, sig);
 }
  
-
-long sys32_io_setup(unsigned nr_reqs, u32 __user *ctx32p)
-{ 
-	long ret; 
-	aio_context_t ctx64;
-	mm_segment_t oldfs = get_fs(); 	
-	set_fs(KERNEL_DS); 
-	ret = sys_io_setup(nr_reqs, &ctx64); 
-	set_fs(oldfs); 
-	/* truncating is ok because it's a user address */
-	if (!ret) 
-		ret = put_user((u32)ctx64, ctx32p);
-	return ret;
-} 
-
 asmlinkage long sys32_io_submit(aio_context_t ctx_id, int nr,
 		   compat_uptr_t __user *iocbpp)
 {