riscv: add do_page_fault and do_trap_break into the kprobes blacklist

These two functions are used to implement the kprobes feature so they
can't be kprobed.

Fixes: c22b0bcb ("riscv: Add kprobes supported")
Cc: stable@vger.kernel.org
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

arch/riscv/kernel/traps.c

@@ -178,6 +178,7 @@ asmlinkage __visible void do_trap_break(struct pt_regs *regs)
 	else
 		die(regs, "Kernel BUG");
 }
+NOKPROBE_SYMBOL(do_trap_break);
 
 #ifdef CONFIG_GENERIC_BUG
 int is_valid_bugaddr(unsigned long pc)

arch/riscv/mm/fault.c

@@ -328,3 +328,4 @@ asmlinkage void do_page_fault(struct pt_regs *regs)
 	}
 	return;
 }
+NOKPROBE_SYMBOL(do_page_fault);