diff --git a/kernel/process/process.rs b/kernel/process/process.rs
index 70ce7969..3f56b4c5 100644
--- a/kernel/process/process.rs
+++ b/kernel/process/process.rs
@@ -15,7 +15,7 @@ use crate::{
         elf::{Elf, ProgramHeader},
         init_stack::{estimate_user_init_stack_size, init_user_stack, Auxv},
         process_group::{PgId, ProcessGroup},
-        signal::{SigAction, Signal, SignalDelivery, SignalMask, SIGCHLD, SIGKILL},
+        signal::{SigAction, SigSet, Signal, SignalDelivery, SignalMask, SIGCHLD, SIGKILL},
         switch, UserVAddr, JOIN_WAIT_QUEUE, SCHEDULER,
     },
     random::read_secure_random,
@@ -38,8 +38,6 @@ use kerla_runtime::{
 };
 use kerla_utils::{alignment::align_up, bitmap::BitMap};
 
-use super::signal::SigSet;
-
 type ProcessTable = BTreeMap<PId, Arc<Process>>;
 
 /// The process table. All processes are registered in with its process Id.
diff --git a/kernel/syscalls/rt_sigprocmask.rs b/kernel/syscalls/rt_sigprocmask.rs
index 40f29437..7c3aae5f 100644
--- a/kernel/syscalls/rt_sigprocmask.rs
+++ b/kernel/syscalls/rt_sigprocmask.rs
@@ -13,10 +13,10 @@ impl SyscallHandler<'_> {
         oldset: Option<UserVAddr>,
         length: usize,
     ) -> Result<isize> {
-        if length != 8{
+        if length != 8 {
             debug_warn!("sys_rt_sigprocmask length argument is not equal 8");
         }
-        
+
         let how = match how {
             0 => SignalMask::Block,
             1 => SignalMask::Unblock,
@@ -24,9 +24,7 @@ impl SyscallHandler<'_> {
             _ => return Err(Errno::EINVAL.into()),
         };
 
-        if let Err(_) = current_process().set_signal_mask(how, set, oldset, length) {
-            return Err(Errno::EFAULT.into());
-        }
+        current_process().set_signal_mask(how, set, oldset, length)?;
 
         Ok(0)
     }