x86/compat: Remove sys32_vm86_warning

The check against lastcomm is racy, and the message it produces
isn't necessary.  vm86 support can be disabled on a 32-bit
kernel also, and doesn't have this message.  Switch to
sys_ni_syscall instead.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1425439896-8322-4-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/ia32/sys_ia32.c

@@ -201,20 +201,6 @@ long sys32_fadvise64_64(int fd, __u32 offset_low, __u32 offset_high,
 				advice);
 }
 
-long sys32_vm86_warning(void)
-{
-	struct task_struct *me = current;
-	static char lastcomm[sizeof(me->comm)];
-
-	if (strncmp(lastcomm, me->comm, sizeof(lastcomm))) {
-		compat_printk(KERN_INFO
-			      "%s: vm86 mode not supported on 64 bit kernel\n",
-			      me->comm);
-		strncpy(lastcomm, me->comm, sizeof(lastcomm));
-	}
-	return -ENOSYS;
-}
-
 asmlinkage ssize_t sys32_readahead(int fd, unsigned off_lo, unsigned off_hi,
 				   size_t count)
 {

arch/x86/syscalls/syscall_32.tbl

@@ -119,7 +119,7 @@
 110	i386	iopl			sys_iopl
 111	i386	vhangup			sys_vhangup
 112	i386	idle
-113	i386	vm86old			sys_vm86old			sys32_vm86_warning
+113	i386	vm86old			sys_vm86old			sys_ni_syscall
 114	i386	wait4			sys_wait4			compat_sys_wait4
 115	i386	swapoff			sys_swapoff
 116	i386	sysinfo			sys_sysinfo			compat_sys_sysinfo
@@ -172,7 +172,7 @@
 163	i386	mremap			sys_mremap
 164	i386	setresuid		sys_setresuid16
 165	i386	getresuid		sys_getresuid16
-166	i386	vm86			sys_vm86			sys32_vm86_warning
+166	i386	vm86			sys_vm86			sys_ni_syscall
 167	i386	query_module
 168	i386	poll			sys_poll
 169	i386	nfsservctl