arm64: Remove unimplemented syscall log message

commit 1962682d2b2fbe6cfa995a85c53c069fadda473e upstream.

Stop printing a (ratelimited) kernel message for each instance of an
unimplemented syscall being called. Userland making an unimplemented
syscall is not necessarily misbehaviour and to be expected with a
current userland running on an older kernel. Also, the current message
looks scary to users but does not actually indicate a real problem nor
help them narrow down the cause. Just rely on sys_ni_syscall() to return
-ENOSYS.

Cc: <stable@vger.kernel.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Michael Weiser <michael.weiser@gmx.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index 02710f99c1374a17a34d602a5c1606b8d98306e8..a8c0fd0574fa2bdf9f68607dad855c8f2714da4a 100644 (file)
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -381,14 +381,6 @@ asmlinkage long do_ni_syscall(struct pt_regs *regs)
        }
 #endif
 
-       if (show_unhandled_signals_ratelimited()) {
-               pr_info("%s[%d]: syscall %d\n", current->comm,
-                       task_pid_nr(current), (int)regs->syscallno);
-               dump_instr("", regs);
-               if (user_mode(regs))
-                       __show_regs(regs);
-       }
-
        return sys_ni_syscall();
 }