diff --git a/lib/std/Io.zig b/lib/std/Io.zig
index 87f342f640316343440e5f93e2c1924b81a51c6e..8d51f649e3e79180860e02c2e4930e975cce7e33 100644
--- a/lib/std/Io.zig
+++ b/lib/std/Io.zig
@@ -1577,11 +1577,11 @@ pub const Mutex = extern struct {
     };
 
     pub fn tryLock(m: *Mutex) bool {
-        return m.state.cmpxchgWeak(.unlocked, .locked_once, .acquire, .monotonic) == null;
+        return m.state.cmpxchgStrong(.unlocked, .locked_once, .acquire, .monotonic) == null;
     }
 
     pub fn lock(m: *Mutex, io: Io) Cancelable!void {
-        const initial_state = m.state.cmpxchgWeak(
+        const initial_state = m.state.cmpxchgStrong(
             .unlocked,
             .locked_once,
             .acquire,
@@ -1602,7 +1602,7 @@ pub const Mutex = extern struct {
     ///
     /// For a description of cancelation and cancelation points, see `Future.cancel`.
     pub fn lockUncancelable(m: *Mutex, io: Io) void {
-        const initial_state = m.state.cmpxchgWeak(
+        const initial_state = m.state.cmpxchgStrong(
             .unlocked,
             .locked_once,
             .acquire,
diff --git a/lib/std/Io/RwLock.zig b/lib/std/Io/RwLock.zig
index 586a94af034d50ed0d632f97abaa29ff29b280b5..7be4f026e16c150feef443286315567add6bf69c 100644
--- a/lib/std/Io/RwLock.zig
+++ b/lib/std/Io/RwLock.zig
@@ -114,8 +114,6 @@ test "internal state" {
 }
 
 test "smoke test" {
-    if (builtin.target.cpu.arch.isAARCH64()) return error.SkipZigTest; // https://codeberg.org/ziglang/zig/issues/31393
-
     const io = testing.io;
 
     var rl: Io.RwLock = .init;
diff --git a/lib/std/atomic.zig b/lib/std/atomic.zig
index 0040dbf735eeaabad5c5d532663757bfb5de5491..89f22a89ccc72b1a962a5f781a7c9692b6174a6c 100644
--- a/lib/std/atomic.zig
+++ b/lib/std/atomic.zig
@@ -509,7 +509,7 @@ pub const Mutex = enum(u8) {
     locked,
 
     pub fn tryLock(m: *Mutex) bool {
-        return @cmpxchgWeak(Mutex, m, .unlocked, .locked, .acquire, .monotonic) == null;
+        return @cmpxchgStrong(Mutex, m, .unlocked, .locked, .acquire, .monotonic) == null;
     }
 
     pub fn unlock(m: *Mutex) void {