diff --git a/orbis-kernel/include/orbis/umtx.hpp b/orbis-kernel/include/orbis/umtx.hpp
index c8f9d73d6..b8b358908 100644
--- a/orbis-kernel/include/orbis/umtx.hpp
+++ b/orbis-kernel/include/orbis/umtx.hpp
@@ -2,54 +2,99 @@
 
 #include "error/ErrorCode.hpp"
 #include "orbis-config.hpp"
+#include "thread/types.hpp"
+#include "time.hpp"
+#include <atomic>
+#include <limits>
 
 namespace orbis {
+inline constexpr ulong kUmtxUnowned = 0;
+inline constexpr ulong kUmtxContested = std::numeric_limits<slong>::min();
+
+inline constexpr auto kUsyncProcessShared = 1;
+
+inline constexpr auto kUmutexUnowned = 0;
+inline constexpr auto kUmutexContested = 0x80000000;
+inline constexpr auto kUmutexErrorCheck = 2;
+inline constexpr auto kUmutexPrioInherit = 4;
+inline constexpr auto kUmutexPrioProtect = 8;
+
+inline constexpr auto kUrwLockPreferReader = 2;
+inline constexpr auto kUrwLockWriteOwner = 0x80000000;
+inline constexpr auto kUrwLockWriteWaiters = 0x40000000;
+inline constexpr auto kUrwLockReadWaiters = 0x20000000;
+inline constexpr auto kUrwLockMaxReaders = 0x1fffffff;
+
+inline constexpr auto kSemNamed = 2;
+
+struct umtx {
+  std::atomic<ulong> owner; // Owner of the mutex
+};
+
+struct umutex {
+  std::atomic<lwpid_t> owner; // Owner of the mutex
+  uint32_t flags;             // Flags of the mutex
+  uint32_t ceilings[2];       // Priority protect ceiling
+  uint32_t spare[4];
+};
+
+struct ucond {
+  std::atomic<uint32_t> has_waiters; // Has waiters in kernel
+  uint32_t flags;                    // Flags of the condition variable
+  uint32_t clockid;                  // Clock id
+  uint32_t spare[1];                 // Spare space
+};
+
+struct urwlock {
+  std::atomic<int32_t> state;
+  uint32_t flags;
+  uint32_t blocked_readers;
+  uint32_t blocked_writers;
+  uint32_t spare[4];
+};
+
+struct usem {
+  std::atomic<uint32_t> has_waiters;
+  std::atomic<uint32_t> count;
+  uint32_t flags;
+};
+
 struct Thread;
-ErrorCode umtx_lock_umtx(Thread *thread, ptr<void> obj, std::int64_t val,
-                         ptr<void> uaddr1, ptr<void> uaddr2);
-ErrorCode umtx_unlock_umtx(Thread *thread, ptr<void> obj, std::int64_t val,
-                           ptr<void> uaddr1, ptr<void> uaddr2);
-ErrorCode umtx_wait(Thread *thread, ptr<void> obj, std::int64_t val,
-                    ptr<void> uaddr1, ptr<void> uaddr2);
-ErrorCode umtx_wake(Thread *thread, ptr<void> obj, std::int64_t val,
-                    ptr<void> uaddr1, ptr<void> uaddr2);
-ErrorCode umtx_trylock_umutex(Thread *thread, ptr<void> obj, std::int64_t val,
-                              ptr<void> uaddr1, ptr<void> uaddr2);
-ErrorCode umtx_lock_umutex(Thread *thread, ptr<void> obj, std::int64_t val,
-                           ptr<void> uaddr1, ptr<void> uaddr2);
-ErrorCode umtx_unlock_umutex(Thread *thread, ptr<void> obj, std::int64_t val,
-                             ptr<void> uaddr1, ptr<void> uaddr2);
-ErrorCode umtx_set_ceiling(Thread *thread, ptr<void> obj, std::int64_t val,
-                           ptr<void> uaddr1, ptr<void> uaddr2);
-ErrorCode umtx_cv_wait(Thread *thread, ptr<void> obj, std::int64_t val,
-                       ptr<void> uaddr1, ptr<void> uaddr2);
-ErrorCode umtx_cv_signal(Thread *thread, ptr<void> obj, std::int64_t val,
-                         ptr<void> uaddr1, ptr<void> uaddr2);
-ErrorCode umtx_cv_broadcast(Thread *thread, ptr<void> obj, std::int64_t val,
-                            ptr<void> uaddr1, ptr<void> uaddr2);
-ErrorCode umtx_wait_uint(Thread *thread, ptr<void> obj, std::int64_t val,
-                         ptr<void> uaddr1, ptr<void> uaddr2);
+ErrorCode umtx_lock_umtx(Thread *thread, ptr<umtx> umtx, ulong id,
+                         timespec *ts);
+ErrorCode umtx_unlock_umtx(Thread *thread, ptr<umtx> umtx, ulong id);
+ErrorCode umtx_wait(Thread *thread, ptr<void> addr, ulong id,
+                    timespec *timeout);
+ErrorCode umtx_wake(Thread *thread, ptr<void> uaddr, sint n_wake);
+ErrorCode umtx_trylock_umutex(Thread *thread, ptr<umutex> m);
+ErrorCode umtx_lock_umutex(Thread *thread, ptr<umutex> m, timespec *timeout);
+ErrorCode umtx_unlock_umutex(Thread *thread, ptr<umutex> m);
+ErrorCode umtx_set_ceiling(Thread *thread, ptr<umutex> m, std::uint32_t ceiling,
+                           ptr<uint32_t> oldCeiling);
+ErrorCode umtx_cv_wait(Thread *thread, ptr<ucond> cv, ptr<umutex> m,
+                       timespec *ts, ulong wflags);
+ErrorCode umtx_cv_signal(Thread *thread, ptr<ucond> cv);
+ErrorCode umtx_cv_broadcast(Thread *thread, ptr<ucond> cv);
+ErrorCode umtx_wait_uint(Thread *thread, ptr<void> addr, ulong id,
+                         timespec *timeout);
 ErrorCode umtx_rw_rdlock(Thread *thread, ptr<void> obj, std::int64_t val,
                          ptr<void> uaddr1, ptr<void> uaddr2);
 ErrorCode umtx_rw_wrlock(Thread *thread, ptr<void> obj, std::int64_t val,
                          ptr<void> uaddr1, ptr<void> uaddr2);
 ErrorCode umtx_rw_unlock(Thread *thread, ptr<void> obj, std::int64_t val,
                          ptr<void> uaddr1, ptr<void> uaddr2);
-ErrorCode umtx_wait_uint_private(Thread *thread, ptr<void> obj,
-                                 std::int64_t val, ptr<void> uaddr1,
-                                 ptr<void> uaddr2);
-ErrorCode umtx_wake_private(Thread *thread, ptr<void> obj, std::int64_t val,
-                            ptr<void> uaddr1, ptr<void> uaddr2);
-ErrorCode umtx_wait_umutex(Thread *thread, ptr<void> obj, std::int64_t val,
-                           ptr<void> uaddr1, ptr<void> uaddr2);
+ErrorCode umtx_wait_uint_private(Thread *thread, ptr<void> addr, ulong id,
+                                 timespec *timeout);
+ErrorCode umtx_wake_private(Thread *thread, ptr<void> uaddr, sint n_wake);
+ErrorCode umtx_wait_umutex(Thread *thread, ptr<umutex> m, timespec *timeout);
 ErrorCode umtx_wake_umutex(Thread *thread, ptr<void> obj, std::int64_t val,
                            ptr<void> uaddr1, ptr<void> uaddr2);
 ErrorCode umtx_sem_wait(Thread *thread, ptr<void> obj, std::int64_t val,
                         ptr<void> uaddr1, ptr<void> uaddr2);
 ErrorCode umtx_sem_wake(Thread *thread, ptr<void> obj, std::int64_t val,
                         ptr<void> uaddr1, ptr<void> uaddr2);
-ErrorCode umtx_nwake_private(Thread *thread, ptr<void> obj, std::int64_t val,
-                             ptr<void> uaddr1, ptr<void> uaddr2);
+ErrorCode umtx_nwake_private(Thread *thread, ptr<void> uaddrs,
+                             std::int64_t count);
 ErrorCode umtx_wake2_umutex(Thread *thread, ptr<void> obj, std::int64_t val,
                             ptr<void> uaddr1, ptr<void> uaddr2);
 } // namespace orbis
\ No newline at end of file
diff --git a/orbis-kernel/src/sys/sys_sce.cpp b/orbis-kernel/src/sys/sys_sce.cpp
index 1a4f9b927..70d0c37c7 100644
--- a/orbis-kernel/src/sys/sys_sce.cpp
+++ b/orbis-kernel/src/sys/sys_sce.cpp
@@ -53,10 +53,6 @@ orbis::SysResult orbis::sys_regmgr_call(Thread *thread, uint32_t op,
     };
 
     auto int_value = reinterpret_cast<nonsys_int *>(value);
-
-    const char *const string = "someString";
-
-    ORBIS_LOG_TODO(__FUNCTION__, string);
     ORBIS_LOG_TODO(
         __FUNCTION__, int_value->encoded_id,
         int_value->encoded_id_parts.data[0],
diff --git a/orbis-kernel/src/sys/sys_umtx.cpp b/orbis-kernel/src/sys/sys_umtx.cpp
index 7feaa5020..48ab55a0e 100644
--- a/orbis-kernel/src/sys/sys_umtx.cpp
+++ b/orbis-kernel/src/sys/sys_umtx.cpp
@@ -1,53 +1,149 @@
 #include "sys/sysproto.hpp"
+#include "time.hpp"
 #include "umtx.hpp"
 
-orbis::SysResult orbis::sys__umtx_lock(Thread *thread, ptr<struct umtx> umtx) {
-  return umtx_lock_umtx(thread, umtx, 0, 0, 0);
+static orbis::ErrorCode ureadTimespec(orbis::timespec &ts,
+                                      orbis::ptr<orbis::timespec> addr) {
+  ts = uread(addr);
+  if (ts.sec < 0 || ts.nsec < 0 || ts.nsec > 1000000000) {
+    return orbis::ErrorCode::INVAL;
+  }
+
+  return {};
 }
-orbis::SysResult orbis::sys__umtx_unlock(Thread *thread,
-                                         ptr<struct umtx> umtx) {
-  return umtx_lock_umtx(thread, umtx, thread->tid, 0, 0);
+
+orbis::SysResult orbis::sys__umtx_lock(Thread *thread, ptr<umtx> umtx) {
+  return umtx_lock_umtx(thread, umtx, thread->tid, nullptr);
+}
+orbis::SysResult orbis::sys__umtx_unlock(Thread *thread, ptr<umtx> umtx) {
+  return umtx_unlock_umtx(thread, umtx, thread->tid);
 }
 orbis::SysResult orbis::sys__umtx_op(Thread *thread, ptr<void> obj, sint op,
                                      ulong val, ptr<void> uaddr1,
                                      ptr<void> uaddr2) {
   switch (op) {
-  case 0:
-    return umtx_lock_umtx(thread, obj, val, uaddr1, uaddr2);
+  case 0: {
+    timespec *ts = nullptr;
+    timespec timeout;
+    if (uaddr2 != nullptr) {
+      auto result = ureadTimespec(timeout, (ptr<timespec>)uaddr2);
+      if (result != ErrorCode{}) {
+        return result;
+      }
+
+      ts = &timeout;
+    }
+
+    return umtx_lock_umtx(thread, (ptr<umtx>)obj, val, ts);
+  }
   case 1:
-    return umtx_unlock_umtx(thread, obj, val, uaddr1, uaddr2);
-  case 2:
-    return umtx_wait(thread, obj, val, uaddr1, uaddr2);
+    return umtx_unlock_umtx(thread, (ptr<umtx>)obj, val);
+  case 2: {
+    timespec *ts = nullptr;
+    timespec timeout;
+    if (uaddr2 != nullptr) {
+      auto result = ureadTimespec(timeout, (ptr<timespec>)uaddr2);
+      if (result != ErrorCode{}) {
+        return result;
+      }
+
+      ts = &timeout;
+    }
+
+    return umtx_wait(thread, obj, val, ts);
+  }
   case 3:
-    return umtx_wake(thread, obj, val, uaddr1, uaddr2);
+    return umtx_wake(thread, obj, val);
   case 4:
-    return umtx_trylock_umutex(thread, obj, val, uaddr1, uaddr2);
-  case 5:
-    return umtx_lock_umutex(thread, obj, val, uaddr1, uaddr2);
+    return umtx_trylock_umutex(thread, (ptr<umutex>)obj);
+  case 5: {
+    timespec *ts = nullptr;
+    timespec timeout;
+    if (uaddr2 != nullptr) {
+      auto result = ureadTimespec(timeout, (ptr<timespec>)uaddr2);
+      if (result != ErrorCode{}) {
+        return result;
+      }
+
+      ts = &timeout;
+    }
+    return umtx_lock_umutex(thread, (ptr<umutex>)obj, ts);
+  }
   case 6:
-    return umtx_unlock_umutex(thread, obj, val, uaddr1, uaddr2);
+    return umtx_unlock_umutex(thread, (ptr<umutex>)obj);
   case 7:
-    return umtx_set_ceiling(thread, obj, val, uaddr1, uaddr2);
-  case 8:
-    return umtx_cv_wait(thread, obj, val, uaddr1, uaddr2);
+    return umtx_set_ceiling(thread, (ptr<umutex>)obj, val,
+                            (ptr<uint32_t>)uaddr1);
+
+  case 8: {
+    timespec *ts = nullptr;
+    timespec timeout;
+    if (uaddr2 != nullptr) {
+      auto result = ureadTimespec(timeout, (ptr<timespec>)uaddr2);
+      if (result != ErrorCode{}) {
+        return result;
+      }
+
+      ts = &timeout;
+    }
+
+    return umtx_cv_wait(thread, (ptr<ucond>)obj, (ptr<umutex>)uaddr1, ts, val);
+  }
+
   case 9:
-    return umtx_cv_signal(thread, obj, val, uaddr1, uaddr2);
+    return umtx_cv_signal(thread, (ptr<ucond>)obj);
   case 10:
-    return umtx_cv_broadcast(thread, obj, val, uaddr1, uaddr2);
-  case 11:
-    return umtx_wait_uint(thread, obj, val, uaddr1, uaddr2);
+    return umtx_cv_broadcast(thread, (ptr<ucond>)obj);
+  case 11: {
+    timespec *ts = nullptr;
+    timespec timeout;
+    if (uaddr2 != nullptr) {
+      auto result = ureadTimespec(timeout, (ptr<timespec>)uaddr2);
+      if (result != ErrorCode{}) {
+        return result;
+      }
+
+      ts = &timeout;
+    }
+
+    return umtx_wait_uint(thread, obj, val, ts);
+  }
   case 12:
     return umtx_rw_rdlock(thread, obj, val, uaddr1, uaddr2);
   case 13:
     return umtx_rw_wrlock(thread, obj, val, uaddr1, uaddr2);
   case 14:
     return umtx_rw_unlock(thread, obj, val, uaddr1, uaddr2);
-  case 15:
-    return umtx_wait_uint_private(thread, obj, val, uaddr1, uaddr2);
+  case 15: {
+    timespec *ts = nullptr;
+    timespec timeout;
+    if (uaddr2 != nullptr) {
+      auto result = ureadTimespec(timeout, (ptr<timespec>)uaddr2);
+      if (result != ErrorCode{}) {
+        return result;
+      }
+
+      ts = &timeout;
+    }
+
+    return umtx_wait_uint_private(thread, obj, val, ts);
+  }
   case 16:
-    return umtx_wake_private(thread, obj, val, uaddr1, uaddr2);
-  case 17:
-    return umtx_wait_umutex(thread, obj, val, uaddr1, uaddr2);
+    return umtx_wake_private(thread, obj, val);
+  case 17: {
+    timespec *ts = nullptr;
+    timespec timeout;
+    if (uaddr2 != nullptr) {
+      auto result = ureadTimespec(timeout, (ptr<timespec>)uaddr2);
+      if (result != ErrorCode{}) {
+        return result;
+      }
+
+      ts = &timeout;
+    }
+
+    return umtx_wait_umutex(thread, (ptr<umutex>)obj, ts);
+  }
   case 18:
     return umtx_wake_umutex(thread, obj, val, uaddr1, uaddr2);
   case 19:
@@ -55,7 +151,7 @@ orbis::SysResult orbis::sys__umtx_op(Thread *thread, ptr<void> obj, sint op,
   case 20:
     return umtx_sem_wake(thread, obj, val, uaddr1, uaddr2);
   case 21:
-    return umtx_nwake_private(thread, obj, val, uaddr1, uaddr2);
+    return umtx_nwake_private(thread, obj, val);
   case 22:
     return umtx_wake2_umutex(thread, obj, val, uaddr1, uaddr2);
   }
diff --git a/orbis-kernel/src/umtx.cpp b/orbis-kernel/src/umtx.cpp
index 32d608d34..00728d532 100644
--- a/orbis-kernel/src/umtx.cpp
+++ b/orbis-kernel/src/umtx.cpp
@@ -1,74 +1,61 @@
 #include "umtx.hpp"
+#include "time.hpp"
 
-orbis::ErrorCode orbis::umtx_lock_umtx(Thread *thread, ptr<void> obj,
-                                       std::int64_t val, ptr<void> uaddr1,
-                                       ptr<void> uaddr2) {
+orbis::ErrorCode orbis::umtx_lock_umtx(Thread *thread, ptr<umtx> umtx, ulong id,
+                                       timespec *ts) {
   return ErrorCode::NOSYS;
 }
 
-orbis::ErrorCode orbis::umtx_unlock_umtx(Thread *thread, ptr<void> obj,
-                                         std::int64_t val, ptr<void> uaddr1,
-                                         ptr<void> uaddr2) {
+orbis::ErrorCode orbis::umtx_unlock_umtx(Thread *thread, ptr<umtx> umtx,
+                                         ulong id) {
   return ErrorCode::NOSYS;
 }
 
-orbis::ErrorCode orbis::umtx_wait(Thread *thread, ptr<void> obj,
-                                  std::int64_t val, ptr<void> uaddr1,
-                                  ptr<void> uaddr2) {
+orbis::ErrorCode orbis::umtx_wait(Thread *thread, ptr<void> addr, ulong id,
+                                  timespec *timeout) {
   return ErrorCode::NOSYS;
 }
 
-orbis::ErrorCode orbis::umtx_wake(Thread *thread, ptr<void> obj,
-                                  std::int64_t val, ptr<void> uaddr1,
-                                  ptr<void> uaddr2) {
+orbis::ErrorCode orbis::umtx_wake(Thread *thread, ptr<void> uaddr,
+                                  sint n_wake) {
   return ErrorCode::NOSYS;
 }
 
-orbis::ErrorCode orbis::umtx_trylock_umutex(Thread *thread, ptr<void> obj,
-                                            std::int64_t val, ptr<void> uaddr1,
-                                            ptr<void> uaddr2) {
+orbis::ErrorCode orbis::umtx_trylock_umutex(Thread *thread, ptr<umutex> m) {
   return ErrorCode::NOSYS;
 }
 
-orbis::ErrorCode orbis::umtx_lock_umutex(Thread *thread, ptr<void> obj,
-                                         std::int64_t val, ptr<void> uaddr1,
-                                         ptr<void> uaddr2) {
+orbis::ErrorCode orbis::umtx_lock_umutex(Thread *thread, ptr<umutex> m,
+                                         timespec *timeout) {
   return ErrorCode::NOSYS;
 }
 
-orbis::ErrorCode orbis::umtx_unlock_umutex(Thread *thread, ptr<void> obj,
-                                           std::int64_t val, ptr<void> uaddr1,
-                                           ptr<void> uaddr2) {
+orbis::ErrorCode orbis::umtx_unlock_umutex(Thread *thread, ptr<umutex> m) {
   return ErrorCode::NOSYS;
 }
 
-orbis::ErrorCode orbis::umtx_set_ceiling(Thread *thread, ptr<void> obj,
-                                         std::int64_t val, ptr<void> uaddr1,
-                                         ptr<void> uaddr2) {
+orbis::ErrorCode orbis::umtx_set_ceiling(Thread *thread, ptr<umutex> m,
+                                         std::uint32_t ceiling,
+                                         ptr<uint32_t> oldCeiling) {
   return ErrorCode::NOSYS;
 }
 
-orbis::ErrorCode orbis::umtx_cv_wait(Thread *thread, ptr<void> obj,
-                                     std::int64_t val, ptr<void> uaddr1,
-                                     ptr<void> uaddr2) {
+orbis::ErrorCode orbis::umtx_cv_wait(Thread *thread, ptr<ucond> cv,
+                                     ptr<umutex> m, timespec *ts,
+                                     ulong wflags) {
   return ErrorCode::NOSYS;
 }
 
-orbis::ErrorCode orbis::umtx_cv_signal(Thread *thread, ptr<void> obj,
-                                       std::int64_t val, ptr<void> uaddr1,
-                                       ptr<void> uaddr2) {
+orbis::ErrorCode orbis::umtx_cv_signal(Thread *thread, ptr<ucond> cv) {
   return ErrorCode::NOSYS;
 }
 
-orbis::ErrorCode orbis::umtx_cv_broadcast(Thread *thread, ptr<void> obj,
-                                          std::int64_t val, ptr<void> uaddr1,
-                                          ptr<void> uaddr2) {
+orbis::ErrorCode orbis::umtx_cv_broadcast(Thread *thread, ptr<ucond> cv) {
   return ErrorCode::NOSYS;
 }
 
-orbis::ErrorCode orbis::umtx_wait_uint(Thread *thread, ptr<void> obj,
-                                       std::int64_t val, ptr<void> uaddr1,
-                                       ptr<void> uaddr2) {
+orbis::ErrorCode orbis::umtx_wait_uint(Thread *thread, ptr<void> addr, ulong id,
+                                       timespec *timeout) {
   return ErrorCode::NOSYS;
 }
 
@@ -90,22 +77,18 @@ orbis::ErrorCode orbis::umtx_rw_unlock(Thread *thread, ptr<void> obj,
   return ErrorCode::NOSYS;
 }
 
-orbis::ErrorCode orbis::umtx_wait_uint_private(Thread *thread, ptr<void> obj,
-                                               std::int64_t val,
-                                               ptr<void> uaddr1,
-                                               ptr<void> uaddr2) {
+orbis::ErrorCode orbis::umtx_wait_uint_private(Thread *thread, ptr<void> addr,
+                                               ulong id, timespec *timeout) {
   return ErrorCode::NOSYS;
 }
 
-orbis::ErrorCode orbis::umtx_wake_private(Thread *thread, ptr<void> obj,
-                                          std::int64_t val, ptr<void> uaddr1,
-                                          ptr<void> uaddr2) {
+orbis::ErrorCode orbis::umtx_wake_private(Thread *thread, ptr<void> uaddr,
+                                          sint n_wake) {
   return ErrorCode::NOSYS;
 }
 
-orbis::ErrorCode orbis::umtx_wait_umutex(Thread *thread, ptr<void> obj,
-                                         std::int64_t val, ptr<void> uaddr1,
-                                         ptr<void> uaddr2) {
+orbis::ErrorCode orbis::umtx_wait_umutex(Thread *thread, ptr<umutex> m,
+                                         timespec *timeout) {
   return ErrorCode::NOSYS;
 }
 
@@ -127,9 +110,8 @@ orbis::ErrorCode orbis::umtx_sem_wake(Thread *thread, ptr<void> obj,
   return ErrorCode::NOSYS;
 }
 
-orbis::ErrorCode orbis::umtx_nwake_private(Thread *thread, ptr<void> obj,
-                                           std::int64_t val, ptr<void> uaddr1,
-                                           ptr<void> uaddr2) {
+orbis::ErrorCode orbis::umtx_nwake_private(Thread *thread, ptr<void> uaddrs,
+                                           std::int64_t count) {
   return ErrorCode::NOSYS;
 }