diff --git a/libstratosphere/include/stratosphere/fs/common/fs_file_storage.hpp b/libstratosphere/include/stratosphere/fs/common/fs_file_storage.hpp
index 3d8f44ec..732c9299 100644
--- a/libstratosphere/include/stratosphere/fs/common/fs_file_storage.hpp
+++ b/libstratosphere/include/stratosphere/fs/common/fs_file_storage.hpp
@@ -92,9 +92,9 @@ namespace ams::fs {
             FileHandle handle;
             bool close_file;
             s64 size;
-            os::Mutex mutex;
+            os::SdkMutex mutex;
         public:
-            constexpr explicit FileHandleStorage(FileHandle handle, bool close_file) : handle(handle), close_file(close_file), size(InvalidSize), mutex(false) { /* ... */ }
+            constexpr explicit FileHandleStorage(FileHandle handle, bool close_file) : handle(handle), close_file(close_file), size(InvalidSize), mutex() { /* ... */ }
             constexpr explicit FileHandleStorage(FileHandle handle) : FileHandleStorage(handle, false) { /* ... */ }
 
             virtual ~FileHandleStorage() override {
diff --git a/libstratosphere/include/stratosphere/fssrv/fssrv_memory_resource_from_exp_heap.hpp b/libstratosphere/include/stratosphere/fssrv/fssrv_memory_resource_from_exp_heap.hpp
index 08540f29..99fdda7f 100644
--- a/libstratosphere/include/stratosphere/fssrv/fssrv_memory_resource_from_exp_heap.hpp
+++ b/libstratosphere/include/stratosphere/fssrv/fssrv_memory_resource_from_exp_heap.hpp
@@ -42,11 +42,11 @@ namespace ams::fssrv {
     class PeakCheckableMemoryResourceFromExpHeap : public ams::MemoryResource {
         private:
             lmem::HeapHandle heap_handle;
-            os::Mutex mutex;
+            os::SdkMutex mutex;
             size_t peak_free_size;
             size_t current_free_size;
         public:
-            constexpr explicit PeakCheckableMemoryResourceFromExpHeap(size_t heap_size) : heap_handle(nullptr), mutex(false), peak_free_size(heap_size), current_free_size(heap_size) { /* ... */ }
+            constexpr explicit PeakCheckableMemoryResourceFromExpHeap(size_t heap_size) : heap_handle(nullptr), mutex(), peak_free_size(heap_size), current_free_size(heap_size) { /* ... */ }
 
             void SetHeapHandle(lmem::HeapHandle handle) {
                 this->heap_handle = handle;
@@ -57,7 +57,7 @@ namespace ams::fssrv {
 
             void ClearPeak() { this->peak_free_size = this->current_free_size; }
 
-            std::scoped_lock<os::Mutex> GetScopedLock() {
+            std::scoped_lock<os::SdkMutex> GetScopedLock() {
                 return std::scoped_lock(this->mutex);
             }
 
diff --git a/libstratosphere/include/stratosphere/fssystem/buffers/fssystem_file_system_buffer_manager.hpp b/libstratosphere/include/stratosphere/fssystem/buffers/fssystem_file_system_buffer_manager.hpp
index e6c37b66..fcd84abe 100644
--- a/libstratosphere/include/stratosphere/fssystem/buffers/fssystem_file_system_buffer_manager.hpp
+++ b/libstratosphere/include/stratosphere/fssystem/buffers/fssystem_file_system_buffer_manager.hpp
@@ -192,7 +192,7 @@ namespace ams::fssystem {
             size_t peak_free_size;
             size_t peak_total_allocatable_size;
             size_t retried_count;
-            mutable os::Mutex mutex;
+            mutable os::SdkRecursiveMutex mutex;
         public:
             static constexpr size_t QueryWorkBufferSize(s32 max_cache_count, s32 max_order) {
                 const auto buddy_size = FileSystemBuddyHeap::QueryWorkBufferSize(max_order);
@@ -200,7 +200,7 @@ namespace ams::fssystem {
                 return buddy_size + table_size;
             }
         public:
-            FileSystemBufferManager() : total_size(), peak_free_size(), peak_total_allocatable_size(), retried_count(), mutex(true) { /* ... */ }
+            FileSystemBufferManager() : total_size(), peak_free_size(), peak_total_allocatable_size(), retried_count(), mutex() { /* ... */ }
 
             virtual ~FileSystemBufferManager() { /* ... */ }
 
diff --git a/libstratosphere/include/stratosphere/fssystem/fssystem_aes_xts_storage.hpp b/libstratosphere/include/stratosphere/fssystem/fssystem_aes_xts_storage.hpp
index f0780a2a..9292339e 100644
--- a/libstratosphere/include/stratosphere/fssystem/fssystem_aes_xts_storage.hpp
+++ b/libstratosphere/include/stratosphere/fssystem/fssystem_aes_xts_storage.hpp
@@ -33,7 +33,7 @@ namespace ams::fssystem {
             char key[2][KeySize];
             char iv[IvSize];
             const size_t block_size;
-            os::Mutex mutex;
+            os::SdkMutex mutex;
         public:
             AesXtsStorage(IStorage *base, const void *key1, const void *key2, size_t key_size, const void *iv, size_t iv_size, size_t block_size);
 
diff --git a/libstratosphere/include/stratosphere/fssystem/fssystem_directory_redirection_filesystem.hpp b/libstratosphere/include/stratosphere/fssystem/fssystem_directory_redirection_filesystem.hpp
index 281b4b99..0bc6645d 100644
--- a/libstratosphere/include/stratosphere/fssystem/fssystem_directory_redirection_filesystem.hpp
+++ b/libstratosphere/include/stratosphere/fssystem/fssystem_directory_redirection_filesystem.hpp
@@ -34,7 +34,7 @@ namespace ams::fssystem {
 
             virtual ~DirectoryRedirectionFileSystem();
         protected:
-            inline util::optional<std::scoped_lock<os::Mutex>> GetAccessorLock() const {
+            inline util::optional<std::scoped_lock<os::SdkMutex>> GetAccessorLock() const {
                 /* No accessor lock is needed. */
                 return util::nullopt;
             }
diff --git a/libstratosphere/include/stratosphere/fssystem/fssystem_directory_savedata_filesystem.hpp b/libstratosphere/include/stratosphere/fssystem/fssystem_directory_savedata_filesystem.hpp
index 026b2d93..54ccfba3 100644
--- a/libstratosphere/include/stratosphere/fssystem/fssystem_directory_savedata_filesystem.hpp
+++ b/libstratosphere/include/stratosphere/fssystem/fssystem_directory_savedata_filesystem.hpp
@@ -24,7 +24,7 @@ namespace ams::fssystem {
             using PathResolutionFileSystem = impl::IPathResolutionFileSystem<DirectorySaveDataFileSystem>;
             friend class impl::IPathResolutionFileSystem<DirectorySaveDataFileSystem>;
         private:
-            os::Mutex accessor_mutex;
+            os::SdkMutex accessor_mutex;
             s32 open_writable_files;
         public:
             DirectorySaveDataFileSystem(std::shared_ptr<fs::fsa::IFileSystem> fs);
@@ -33,9 +33,9 @@ namespace ams::fssystem {
 
             virtual ~DirectorySaveDataFileSystem();
         protected:
-            inline util::optional<std::scoped_lock<os::Mutex>> GetAccessorLock() {
+            inline util::optional<std::scoped_lock<os::SdkMutex>> GetAccessorLock() {
                 /* We have a real accessor lock that we want to use. */
-                return util::make_optional<std::scoped_lock<os::Mutex>>(this->accessor_mutex);
+                return util::make_optional<std::scoped_lock<os::SdkMutex>>(this->accessor_mutex);
             }
         private:
             Result AllocateWorkBuffer(std::unique_ptr<u8[]> *out, size_t *out_size, size_t ideal_size);
diff --git a/libstratosphere/include/stratosphere/fssystem/fssystem_integrity_romfs_storage.hpp b/libstratosphere/include/stratosphere/fssystem/fssystem_integrity_romfs_storage.hpp
index fdc9d15b..8c0414a2 100644
--- a/libstratosphere/include/stratosphere/fssystem/fssystem_integrity_romfs_storage.hpp
+++ b/libstratosphere/include/stratosphere/fssystem/fssystem_integrity_romfs_storage.hpp
@@ -30,11 +30,11 @@ namespace ams::fssystem {
         private:
             save::HierarchicalIntegrityVerificationStorage integrity_storage;
             save::FileSystemBufferManagerSet buffers;
-            os::Mutex mutex;
+            os::SdkRecursiveMutex mutex;
             Hash master_hash;
             std::unique_ptr<fs::MemoryStorage> master_hash_storage;
         public:
-            IntegrityRomFsStorage() : mutex(true) { /* ... */ }
+            IntegrityRomFsStorage() : mutex() { /* ... */ }
             virtual ~IntegrityRomFsStorage() override { this->Finalize(); }
 
             Result Initialize(save::HierarchicalIntegrityVerificationInformation level_hash_info, Hash master_hash, save::HierarchicalIntegrityVerificationStorage::HierarchicalStorageInformation storage_info, IBufferManager *bm);
diff --git a/libstratosphere/include/stratosphere/fssystem/fssystem_subdirectory_filesystem.hpp b/libstratosphere/include/stratosphere/fssystem/fssystem_subdirectory_filesystem.hpp
index e30e74db..61ac5dd3 100644
--- a/libstratosphere/include/stratosphere/fssystem/fssystem_subdirectory_filesystem.hpp
+++ b/libstratosphere/include/stratosphere/fssystem/fssystem_subdirectory_filesystem.hpp
@@ -32,7 +32,7 @@ namespace ams::fssystem {
 
             virtual ~SubDirectoryFileSystem();
         protected:
-            inline util::optional<std::scoped_lock<os::Mutex>> GetAccessorLock() const {
+            inline util::optional<std::scoped_lock<os::SdkMutex>> GetAccessorLock() const {
                 /* No accessor lock is needed. */
                 return util::nullopt;
             }
diff --git a/libstratosphere/include/stratosphere/fssystem/save/fssystem_block_cache_buffered_storage.hpp b/libstratosphere/include/stratosphere/fssystem/save/fssystem_block_cache_buffered_storage.hpp
index b93ca024..38728042 100644
--- a/libstratosphere/include/stratosphere/fssystem/save/fssystem_block_cache_buffered_storage.hpp
+++ b/libstratosphere/include/stratosphere/fssystem/save/fssystem_block_cache_buffered_storage.hpp
@@ -62,7 +62,7 @@ namespace ams::fssystem::save {
             };
         private:
             IBufferManager *buffer_manager;
-            os::Mutex *mutex;
+            os::SdkRecursiveMutex *mutex;
             std::unique_ptr<CacheEntry[], ::ams::fs::impl::Deleter> entries;
             IStorage *data_storage;
             Result last_result;
@@ -78,7 +78,7 @@ namespace ams::fssystem::save {
             BlockCacheBufferedStorage();
             virtual ~BlockCacheBufferedStorage() override;
 
-            Result Initialize(IBufferManager *bm, os::Mutex *mtx, IStorage *data, s64 data_size, size_t verif_block_size, s32 max_cache_entries, bool is_real_data, s8 buffer_level, bool is_keep_burst_mode, fs::StorageType storage_type);
+            Result Initialize(IBufferManager *bm, os::SdkRecursiveMutex *mtx, IStorage *data, s64 data_size, size_t verif_block_size, s32 max_cache_entries, bool is_real_data, s8 buffer_level, bool is_keep_burst_mode, fs::StorageType storage_type);
             void Finalize();
 
             virtual Result Read(s64 offset, void *buffer, size_t size) override;
diff --git a/libstratosphere/include/stratosphere/fssystem/save/fssystem_buffered_storage.hpp b/libstratosphere/include/stratosphere/fssystem/save/fssystem_buffered_storage.hpp
index eb30a8a7..8c5ca9db 100644
--- a/libstratosphere/include/stratosphere/fssystem/save/fssystem_buffered_storage.hpp
+++ b/libstratosphere/include/stratosphere/fssystem/save/fssystem_buffered_storage.hpp
@@ -38,7 +38,7 @@ namespace ams::fssystem::save {
             s32 cache_count;
             Cache *next_acquire_cache;
             Cache *next_fetch_cache;
-            os::Mutex mutex;
+            os::SdkMutex mutex;
             bool bulk_read_enabled;
         public:
             BufferedStorage();
diff --git a/libstratosphere/include/stratosphere/fssystem/save/fssystem_hierarchical_integrity_verification_storage.hpp b/libstratosphere/include/stratosphere/fssystem/save/fssystem_hierarchical_integrity_verification_storage.hpp
index 1283a2ac..23b34901 100644
--- a/libstratosphere/include/stratosphere/fssystem/save/fssystem_hierarchical_integrity_verification_storage.hpp
+++ b/libstratosphere/include/stratosphere/fssystem/save/fssystem_hierarchical_integrity_verification_storage.hpp
@@ -147,7 +147,7 @@ namespace ams::fssystem::save {
             }
         private:
             FileSystemBufferManagerSet *buffers;
-            os::Mutex *mutex;
+            os::SdkRecursiveMutex *mutex;
             IntegrityVerificationStorage verify_storages[MaxLayers - 1];
             BlockCacheBufferedStorage    buffer_storages[MaxLayers - 1];
             s64 data_size;
@@ -157,7 +157,7 @@ namespace ams::fssystem::save {
             HierarchicalIntegrityVerificationStorage() : buffers(nullptr), mutex(nullptr), data_size(-1), is_written_for_rollback(false) { /* ... */ }
             virtual ~HierarchicalIntegrityVerificationStorage() override { this->Finalize(); }
 
-            Result Initialize(const HierarchicalIntegrityVerificationInformation &info, HierarchicalStorageInformation storage, FileSystemBufferManagerSet *bufs, os::Mutex *mtx, fs::StorageType storage_type);
+            Result Initialize(const HierarchicalIntegrityVerificationInformation &info, HierarchicalStorageInformation storage, FileSystemBufferManagerSet *bufs, os::SdkRecursiveMutex *mtx, fs::StorageType storage_type);
             void Finalize();
 
             virtual Result Read(s64 offset, void *buffer, size_t size) override;
diff --git a/libstratosphere/include/stratosphere/kvdb/kvdb_file_key_value_store.hpp b/libstratosphere/include/stratosphere/kvdb/kvdb_file_key_value_store.hpp
index 707968e7..537a1fc9 100644
--- a/libstratosphere/include/stratosphere/kvdb/kvdb_file_key_value_store.hpp
+++ b/libstratosphere/include/stratosphere/kvdb/kvdb_file_key_value_store.hpp
@@ -63,14 +63,14 @@ namespace ams::kvdb {
                     bool Contains(const void *key, size_t key_size);
             };
         private:
-            os::Mutex lock;
+            os::SdkMutex lock;
             Path dir_path;
             Cache cache;
         private:
             Path GetPath(const void *key, size_t key_size);
             Result GetKey(size_t *out_size, void *out_key, size_t max_out_size, const FileName &file_name);
         public:
-            FileKeyValueStore() : lock(false) { /* ... */ }
+            FileKeyValueStore() : lock() { /* ... */ }
 
             /* Basic accessors. */
             Result Initialize(const char *dir);
diff --git a/libstratosphere/include/stratosphere/lmem/impl/lmem_impl_common.hpp b/libstratosphere/include/stratosphere/lmem/impl/lmem_impl_common.hpp
index 4cc2240a..3009fa42 100644
--- a/libstratosphere/include/stratosphere/lmem/impl/lmem_impl_common.hpp
+++ b/libstratosphere/include/stratosphere/lmem/impl/lmem_impl_common.hpp
@@ -85,7 +85,7 @@ namespace ams::lmem::impl {
 
         void *heap_start;
         void *heap_end;
-        os::MutexType mutex;
+        os::SdkMutexType mutex;
         u8 option;
         ImplementationHeapHead impl_head;
     };
diff --git a/libstratosphere/include/stratosphere/lr/lr_location_resolver_manager_impl.hpp b/libstratosphere/include/stratosphere/lr/lr_location_resolver_manager_impl.hpp
index 0d9f57ac..0405114f 100644
--- a/libstratosphere/include/stratosphere/lr/lr_location_resolver_manager_impl.hpp
+++ b/libstratosphere/include/stratosphere/lr/lr_location_resolver_manager_impl.hpp
@@ -28,7 +28,7 @@ namespace ams::lr {
             sf::SharedPointer<IRegisteredLocationResolver> registered_location_resolver = nullptr;
             sf::SharedPointer<IAddOnContentLocationResolver> add_on_content_location_resolver = nullptr;
 
-            os::Mutex mutex{false};
+            os::SdkMutex mutex{};
         public:
             /* Actual commands. */
             Result OpenLocationResolver(sf::Out<sf::SharedPointer<ILocationResolver>> out, ncm::StorageId storage_id);
diff --git a/libstratosphere/include/stratosphere/ncm/ncm_content_manager_impl.hpp b/libstratosphere/include/stratosphere/ncm/ncm_content_manager_impl.hpp
index a0e25cf9..b52f9b86 100644
--- a/libstratosphere/include/stratosphere/ncm/ncm_content_manager_impl.hpp
+++ b/libstratosphere/include/stratosphere/ncm/ncm_content_manager_impl.hpp
@@ -102,7 +102,7 @@ namespace ams::ncm {
                 ContentMetaDatabaseRoot() { /* ... */ }
             };
         private:
-            os::Mutex mutex;
+            os::SdkRecursiveMutex mutex;
             bool initialized;
             ContentStorageRoot content_storage_roots[MaxContentStorageRoots];
             ContentMetaDatabaseRoot content_meta_database_roots[MaxContentMetaDatabaseRoots];
@@ -111,8 +111,8 @@ namespace ams::ncm {
             RightsIdCache rights_id_cache;
             RegisteredHostContent registered_host_content;
         public:
-            ContentManagerImpl() : mutex(true), initialized(false), num_content_storage_entries(0), num_content_meta_entries(0), rights_id_cache(), registered_host_content() { 
-                /* ... */ 
+            ContentManagerImpl() : mutex(), initialized(false), num_content_storage_entries(0), num_content_meta_entries(0), rights_id_cache(), registered_host_content() {
+                /* ... */
             };
             ~ContentManagerImpl();
         public:
diff --git a/libstratosphere/include/stratosphere/ncm/ncm_install_task_base.hpp b/libstratosphere/include/stratosphere/ncm/ncm_install_task_base.hpp
index 3e72ff48..936d28ac 100644
--- a/libstratosphere/include/stratosphere/ncm/ncm_install_task_base.hpp
+++ b/libstratosphere/include/stratosphere/ncm/ncm_install_task_base.hpp
@@ -86,13 +86,13 @@ namespace ams::ncm {
             StorageId install_storage;
             InstallTaskDataBase *data;
             InstallProgress progress;
-            os::Mutex progress_mutex;
+            os::SdkMutex progress_mutex;
             u32 config;
-            os::Mutex cancel_mutex;
+            os::SdkMutex cancel_mutex;
             bool cancel_requested;
             InstallThroughput throughput;
             TimeSpan throughput_start_time;
-            os::Mutex throughput_mutex;
+            os::SdkMutex throughput_mutex;
             FirmwareVariationId firmware_variation_id;
         private:
             ALWAYS_INLINE Result SetLastResultOnFailure(Result result) {
@@ -102,7 +102,7 @@ namespace ams::ncm {
                 return result;
             }
         public:
-            InstallTaskBase() : data(), progress(), progress_mutex(false), cancel_mutex(false), cancel_requested(), throughput_mutex(false) { /* ... */ }
+            InstallTaskBase() : data(), progress(), progress_mutex(), cancel_mutex(), cancel_requested(), throughput_mutex() { /* ... */ }
             virtual ~InstallTaskBase() { /* ... */ };
         public:
             virtual void Cancel();
diff --git a/libstratosphere/include/stratosphere/ncm/ncm_memory_report.hpp b/libstratosphere/include/stratosphere/ncm/ncm_memory_report.hpp
index a825fb17..9a1f1a98 100644
--- a/libstratosphere/include/stratosphere/ncm/ncm_memory_report.hpp
+++ b/libstratosphere/include/stratosphere/ncm/ncm_memory_report.hpp
@@ -40,13 +40,13 @@ namespace ams::ncm {
 
     class HeapState {
         private:
-            os::Mutex mutex;
+            os::SdkMutex mutex;
             lmem::HeapHandle heap_handle;
             size_t total_alloc_size;
             size_t peak_total_alloc_size;
             size_t peak_alloc_size;
         public:
-            constexpr HeapState() : mutex(false), heap_handle(nullptr), total_alloc_size(0), peak_total_alloc_size(0), peak_alloc_size(0) { /* ... */ }
+            constexpr HeapState() : mutex(), heap_handle(nullptr), total_alloc_size(0), peak_total_alloc_size(0), peak_alloc_size(0) { /* ... */ }
 
             void Initialize(lmem::HeapHandle heap_handle);
             void Allocate(size_t size);
diff --git a/libstratosphere/include/stratosphere/sf/cmif/sf_cmif_domain_manager.hpp b/libstratosphere/include/stratosphere/sf/cmif/sf_cmif_domain_manager.hpp
index e59d54ca..e2b8e624 100644
--- a/libstratosphere/include/stratosphere/sf/cmif/sf_cmif_domain_manager.hpp
+++ b/libstratosphere/include/stratosphere/sf/cmif/sf_cmif_domain_manager.hpp
@@ -84,7 +84,7 @@ namespace ams::sf::cmif {
                 private:
                     using EntryList = typename util::IntrusiveListMemberTraits<&Entry::free_list_node>::ListType;
                 private:
-                    os::Mutex lock;
+                    os::SdkMutex lock;
                     EntryList free_list;
                     Entry *entries;
                     size_t num_entries;
@@ -114,13 +114,13 @@ namespace ams::sf::cmif {
                     }
             };
         private:
-            os::Mutex entry_owner_lock;
+            os::SdkMutex entry_owner_lock;
             EntryManager entry_manager;
         private:
             virtual void *AllocateDomain()   = 0;
             virtual void  FreeDomain(void *) = 0;
         protected:
-            ServerDomainManager(DomainEntryStorage *entry_storage, size_t entry_count) : entry_owner_lock(false), entry_manager(entry_storage, entry_count) { /* ... */ }
+            ServerDomainManager(DomainEntryStorage *entry_storage, size_t entry_count) : entry_owner_lock(), entry_manager(entry_storage, entry_count) { /* ... */ }
 
             inline DomainServiceObject *AllocateDomainServiceObject() {
                 void *storage = this->AllocateDomain();
diff --git a/libstratosphere/include/stratosphere/sf/hipc/sf_hipc_server_manager.hpp b/libstratosphere/include/stratosphere/sf/hipc/sf_hipc_server_manager.hpp
index d611f5d1..0f1b2e4a 100644
--- a/libstratosphere/include/stratosphere/sf/hipc/sf_hipc_server_manager.hpp
+++ b/libstratosphere/include/stratosphere/sf/hipc/sf_hipc_server_manager.hpp
@@ -80,9 +80,9 @@ namespace ams::sf::hipc {
             os::Event notify_event;
             os::WaitableHolderType notify_event_holder;
 
-            os::Mutex waitable_selection_mutex;
+            os::SdkMutex waitable_selection_mutex;
 
-            os::Mutex waitlist_mutex;
+            os::SdkMutex waitlist_mutex;
             os::WaitableManagerType waitlist;
         private:
             virtual void RegisterSessionToWaitList(ServerSession *session) override final;
@@ -192,7 +192,7 @@ namespace ams::sf::hipc {
             ServerManagerBase(DomainEntryStorage *entry_storage, size_t entry_count) :
                 ServerDomainSessionManager(entry_storage, entry_count),
                 request_stop_event(os::EventClearMode_ManualClear), notify_event(os::EventClearMode_ManualClear),
-                waitable_selection_mutex(false), waitlist_mutex(false)
+                waitable_selection_mutex(), waitlist_mutex()
             {
                 /* Link waitables. */
                 os::InitializeWaitableManager(std::addressof(this->waitable_manager));
@@ -259,7 +259,7 @@ namespace ams::sf::hipc {
             using ServerManagerBase::DomainStorage;
         private:
             /* Resource storage. */
-            os::Mutex resource_mutex;
+            os::SdkMutex resource_mutex;
             util::TypedStorage<Server> server_storages[MaxServers];
             bool server_allocated[MaxServers];
             util::TypedStorage<ServerSession> session_storages[MaxSessions];
@@ -370,7 +370,7 @@ namespace ams::sf::hipc {
                 return this->GetObjectBySessionIndex(session, this->saved_messages_start, hipc::TlsMessageBufferSize);
             }
         public:
-            ServerManager() : ServerManagerBase(this->domain_entry_storages, ManagerOptions::MaxDomainObjects), resource_mutex(false) {
+            ServerManager() : ServerManagerBase(this->domain_entry_storages, ManagerOptions::MaxDomainObjects), resource_mutex() {
                 /* Clear storages. */
                 #define SF_SM_MEMCLEAR(obj) if constexpr (sizeof(obj) > 0) { std::memset(obj, 0, sizeof(obj)); }
                 SF_SM_MEMCLEAR(this->server_storages);
diff --git a/libstratosphere/include/stratosphere/tipc/tipc_server_manager.hpp b/libstratosphere/include/stratosphere/tipc/tipc_server_manager.hpp
index 05c9b418..33df54dc 100644
--- a/libstratosphere/include/stratosphere/tipc/tipc_server_manager.hpp
+++ b/libstratosphere/include/stratosphere/tipc/tipc_server_manager.hpp
@@ -355,7 +355,7 @@ namespace ams::tipc {
 
             using PortAllocatorTuple = std::tuple<typename PortInfos::Allocator...>;
         private:
-            os::Mutex m_mutex;
+            os::SdkRecursiveMutex m_mutex;
             os::TlsSlot m_tls_slot;
             PortManagerTuple m_port_managers;
             PortAllocatorTuple m_port_allocators;
@@ -390,11 +390,11 @@ namespace ams::tipc {
                 os::StartThread(m_port_threads + Ix);
             }
         public:
-            ServerManagerImpl() : m_mutex(true), m_tls_slot(), m_port_managers(), m_port_allocators() { /* ... */ }
+            ServerManagerImpl() : m_mutex(), m_tls_slot(), m_port_managers(), m_port_allocators() { /* ... */ }
 
             os::TlsSlot GetTlsSlot() const { return m_tls_slot; }
 
-            os::Mutex &GetMutex() { return m_mutex; }
+            os::SdkRecursiveMutex &GetMutex() { return m_mutex; }
 
             void Initialize() {
                 /* Initialize our tls slot. */
diff --git a/libstratosphere/source/cfg/cfg_privileged_process.cpp b/libstratosphere/source/cfg/cfg_privileged_process.cpp
index 0fe262a8..a517b24f 100644
--- a/libstratosphere/source/cfg/cfg_privileged_process.cpp
+++ b/libstratosphere/source/cfg/cfg_privileged_process.cpp
@@ -24,10 +24,10 @@ namespace ams::cfg {
         constexpr os::ProcessId InitialProcessIdMaxDeprecated = {0x50};
 
         /* Privileged process globals. */
-        os::Mutex g_lock(false);
-        bool g_got_privileged_process_status = false;
-        os::ProcessId g_min_initial_process_id = os::InvalidProcessId, g_max_initial_process_id = os::InvalidProcessId;
-        os::ProcessId g_cur_process_id = os::InvalidProcessId;
+        constinit os::SdkMutex g_lock;
+        constinit bool g_got_privileged_process_status = false;
+        constinit os::ProcessId g_min_initial_process_id = os::InvalidProcessId, g_max_initial_process_id = os::InvalidProcessId;
+        constinit os::ProcessId g_cur_process_id = os::InvalidProcessId;
 
         /* SD card helpers. */
         void GetPrivilegedProcessIdRange(os::ProcessId *out_min, os::ProcessId *out_max) {
diff --git a/libstratosphere/source/cfg/cfg_sd_card.cpp b/libstratosphere/source/cfg/cfg_sd_card.cpp
index cbf60a72..84a96c77 100644
--- a/libstratosphere/source/cfg/cfg_sd_card.cpp
+++ b/libstratosphere/source/cfg/cfg_sd_card.cpp
@@ -29,9 +29,9 @@ namespace ams::cfg {
         constexpr size_t NumRequiredServicesForSdCardAccess = util::size(RequiredServicesForSdCardAccess);
 
         /* SD card globals. */
-        os::Mutex g_sd_card_lock(false);
-        bool g_sd_card_initialized = false;
-        FsFileSystem g_sd_card_filesystem = {};
+        constinit os::SdkMutex g_sd_card_lock;
+        constinit bool g_sd_card_initialized = false;
+        constinit FsFileSystem g_sd_card_filesystem = {};
 
         /* SD card helpers. */
         Result CheckSdCardServicesReady() {
diff --git a/libstratosphere/source/diag/diag_assertion_impl.cpp b/libstratosphere/source/diag/diag_assertion_impl.cpp
index 77e41c0b..d075194a 100644
--- a/libstratosphere/source/diag/diag_assertion_impl.cpp
+++ b/libstratosphere/source/diag/diag_assertion_impl.cpp
@@ -44,8 +44,8 @@ namespace ams::diag {
         inline void DebugLog(const char *format, ...) __attribute__((format(printf, 1, 2)));
 
 #ifdef AMS_ENABLE_DETAILED_ASSERTIONS
-        os::Mutex g_debug_log_lock(true);
-        char g_debug_buffer[0x400];
+        constinit os::SdkRecursiveMutex g_debug_log_lock;
+        constinit char g_debug_buffer[0x400];
 
         void DebugLogImpl(const char *format, ::std::va_list vl) {
             std::scoped_lock lk(g_debug_log_lock);
diff --git a/libstratosphere/source/fs/fsa/fs_filesystem_accessor.cpp b/libstratosphere/source/fs/fsa/fs_filesystem_accessor.cpp
index 10b2e3ec..28fd3cea 100644
--- a/libstratosphere/source/fs/fsa/fs_filesystem_accessor.cpp
+++ b/libstratosphere/source/fs/fsa/fs_filesystem_accessor.cpp
@@ -60,7 +60,7 @@ namespace ams::fs::impl {
     }
 
     FileSystemAccessor::FileSystemAccessor(const char *n, std::unique_ptr<fsa::IFileSystem> &&fs, std::unique_ptr<fsa::ICommonMountNameGenerator> &&generator)
-        : impl(std::move(fs)), open_list_lock(false), mount_name_generator(std::move(generator)),
+        : impl(std::move(fs)), open_list_lock(), mount_name_generator(std::move(generator)),
           access_log_enabled(false), data_cache_attachable(false), path_cache_attachable(false), path_cache_attached(false), multi_commit_supported(false)
     {
         R_ABORT_UNLESS(ValidateMountName(n));
diff --git a/libstratosphere/source/fs/fsa/fs_filesystem_accessor.hpp b/libstratosphere/source/fs/fsa/fs_filesystem_accessor.hpp
index 856059c1..4e20419b 100644
--- a/libstratosphere/source/fs/fsa/fs_filesystem_accessor.hpp
+++ b/libstratosphere/source/fs/fsa/fs_filesystem_accessor.hpp
@@ -35,7 +35,7 @@ namespace ams::fs::impl {
             std::unique_ptr<fsa::IFileSystem> impl;
             FileList open_file_list;
             DirList open_dir_list;
-            os::Mutex open_list_lock;
+            os::SdkMutex open_list_lock;
             std::unique_ptr<fsa::ICommonMountNameGenerator> mount_name_generator;
             bool access_log_enabled;
             bool data_cache_attachable;
diff --git a/libstratosphere/source/fs/fsa/fs_mount_table.hpp b/libstratosphere/source/fs/fsa/fs_mount_table.hpp
index e0034588..59fe63b2 100644
--- a/libstratosphere/source/fs/fsa/fs_mount_table.hpp
+++ b/libstratosphere/source/fs/fsa/fs_mount_table.hpp
@@ -26,9 +26,9 @@ namespace ams::fs::impl {
             using FileSystemList = util::IntrusiveListBaseTraits<FileSystemAccessor>::ListType;
         private:
             FileSystemList fs_list;
-            os::Mutex mutex;
+            os::SdkMutex mutex;
         public:
-            constexpr MountTable() : fs_list(), mutex(false) { /* ... */ }
+            constexpr MountTable() : fs_list(), mutex() { /* ... */ }
         private:
             bool CanAcceptMountName(const char *name);
         public:
diff --git a/libstratosphere/source/fssystem/fssystem_aes_xts_storage.cpp b/libstratosphere/source/fssystem/fssystem_aes_xts_storage.cpp
index 959725bd..db19eceb 100644
--- a/libstratosphere/source/fssystem/fssystem_aes_xts_storage.cpp
+++ b/libstratosphere/source/fssystem/fssystem_aes_xts_storage.cpp
@@ -17,7 +17,7 @@
 
 namespace ams::fssystem {
 
-    AesXtsStorage::AesXtsStorage(IStorage *base, const void *key1, const void *key2, size_t key_size, const void *iv, size_t iv_size, size_t block_size) : base_storage(base), block_size(block_size), mutex(false) {
+    AesXtsStorage::AesXtsStorage(IStorage *base, const void *key1, const void *key2, size_t key_size, const void *iv, size_t iv_size, size_t block_size) : base_storage(base), block_size(block_size), mutex() {
         AMS_ASSERT(base != nullptr);
         AMS_ASSERT(key1 != nullptr);
         AMS_ASSERT(key2 != nullptr);
diff --git a/libstratosphere/source/fssystem/fssystem_directory_savedata_filesystem.cpp b/libstratosphere/source/fssystem/fssystem_directory_savedata_filesystem.cpp
index 8f60adee..5f00412b 100644
--- a/libstratosphere/source/fssystem/fssystem_directory_savedata_filesystem.cpp
+++ b/libstratosphere/source/fssystem/fssystem_directory_savedata_filesystem.cpp
@@ -74,13 +74,13 @@ namespace ams::fssystem {
     }
 
     DirectorySaveDataFileSystem::DirectorySaveDataFileSystem(std::shared_ptr<fs::fsa::IFileSystem> fs)
-        : PathResolutionFileSystem(fs), accessor_mutex(false), open_writable_files(0)
+        : PathResolutionFileSystem(fs), accessor_mutex(), open_writable_files(0)
     {
         /* ... */
     }
 
     DirectorySaveDataFileSystem::DirectorySaveDataFileSystem(std::unique_ptr<fs::fsa::IFileSystem> fs)
-        : PathResolutionFileSystem(std::move(fs)), accessor_mutex(false), open_writable_files(0)
+        : PathResolutionFileSystem(std::move(fs)), accessor_mutex(), open_writable_files(0)
     {
         /* ... */
     }
diff --git a/libstratosphere/source/fssystem/fssystem_hierarchical_sha256_storage.hpp b/libstratosphere/source/fssystem/fssystem_hierarchical_sha256_storage.hpp
index 5ef4a008..16b461c6 100644
--- a/libstratosphere/source/fssystem/fssystem_hierarchical_sha256_storage.hpp
+++ b/libstratosphere/source/fssystem/fssystem_hierarchical_sha256_storage.hpp
@@ -25,7 +25,7 @@ namespace ams::fssystem {
             static constexpr s32 LayerCount  = 3;
             static constexpr size_t HashSize = crypto::Sha256Generator::HashSize;
         private:
-            os::Mutex mutex;
+            os::SdkMutex mutex;
             IStorage *base_storage;
             s64 base_storage_size;
             char *hash_buffer;
@@ -33,7 +33,7 @@ namespace ams::fssystem {
             s32 hash_target_block_size;
             s32 log_size_ratio;
         public:
-            HierarchicalSha256Storage() : mutex(false) { /* ... */ }
+            HierarchicalSha256Storage() : mutex() { /* ... */ }
 
             Result Initialize(IStorage **base_storages, s32 layer_count, size_t htbs, void *hash_buf, size_t hash_buf_size);
 
diff --git a/libstratosphere/source/fssystem/fssystem_key_slot_cache.hpp b/libstratosphere/source/fssystem/fssystem_key_slot_cache.hpp
index 6b4f9234..0cf1f5e2 100644
--- a/libstratosphere/source/fssystem/fssystem_key_slot_cache.hpp
+++ b/libstratosphere/source/fssystem/fssystem_key_slot_cache.hpp
@@ -22,10 +22,10 @@ namespace ams::fssystem {
         NON_COPYABLE(KeySlotCacheAccessor);
         NON_MOVEABLE(KeySlotCacheAccessor);
         private:
-            util::unique_lock<os::Mutex> lk;
+            util::unique_lock<os::SdkMutex> lk;
             const s32 slot_index;
         public:
-            KeySlotCacheAccessor(s32 idx, util::unique_lock<os::Mutex> &&l) : lk(std::move(l)), slot_index(idx) { /* ... */ }
+            KeySlotCacheAccessor(s32 idx, util::unique_lock<os::SdkMutex> &&l) : lk(std::move(l)), slot_index(idx) { /* ... */ }
 
             s32 GetKeySlotIndex() const { return this->slot_index; }
     };
@@ -64,11 +64,11 @@ namespace ams::fssystem {
         private:
             using KeySlotCacheEntryList = util::IntrusiveListBaseTraits<KeySlotCacheEntry>::ListType;
         private:
-            os::Mutex mutex;
+            os::SdkMutex mutex;
             KeySlotCacheEntryList high_priority_mru_list;
             KeySlotCacheEntryList low_priority_mru_list;
         public:
-            constexpr KeySlotCache() : mutex(false), high_priority_mru_list(), low_priority_mru_list() { /* ... */ }
+            constexpr KeySlotCache() : mutex(), high_priority_mru_list(), low_priority_mru_list() { /* ... */ }
 
             Result AllocateHighPriority(std::unique_ptr<KeySlotCacheAccessor> *out, const void *key, size_t key_size, s32 key2) {
                 return this->AllocateFromLru(out, this->high_priority_mru_list, key, key_size, key2);
diff --git a/libstratosphere/source/fssystem/fssystem_pooled_buffer.cpp b/libstratosphere/source/fssystem/fssystem_pooled_buffer.cpp
index 7d36e991..0ec3e1e4 100644
--- a/libstratosphere/source/fssystem/fssystem_pooled_buffer.cpp
+++ b/libstratosphere/source/fssystem/fssystem_pooled_buffer.cpp
@@ -21,13 +21,12 @@ namespace ams::fssystem {
 
         class AdditionalDeviceAddressEntry {
             private:
-                /* TODO: SdkMutex */
-                os::Mutex mutex;
+                os::SdkMutex mutex;
                 bool is_registered;
                 uintptr_t address;
                 size_t size;
             public:
-                constexpr AdditionalDeviceAddressEntry() : mutex(false), is_registered(), address(), size() { /* ... */ }
+                constexpr AdditionalDeviceAddressEntry() : mutex(), is_registered(), address(), size() { /* ... */ }
 
                 void Register(uintptr_t addr, size_t sz) {
                     std::scoped_lock lk(this->mutex);
@@ -77,18 +76,17 @@ namespace ams::fssystem {
         constexpr size_t HeapAllocatableSizeMax         = HeapBlockSize * (static_cast<size_t>(1) << HeapOrderMax);
         constexpr size_t HeapAllocatableSizeMaxForLarge = HeapBlockSize * (static_cast<size_t>(1) << HeapOrderMaxForLarge);
 
-        /* TODO: SdkMutex */
-        os::Mutex g_heap_mutex(false);
-        FileSystemBuddyHeap g_heap;
+        constinit os::SdkMutex g_heap_mutex;
+        constinit FileSystemBuddyHeap g_heap;
 
-        std::atomic<size_t> g_retry_count;
-        std::atomic<size_t> g_reduce_allocation_count;
+        constinit std::atomic<size_t> g_retry_count;
+        constinit std::atomic<size_t> g_reduce_allocation_count;
 
-        void *g_heap_buffer;
-        size_t g_heap_size;
-        size_t g_heap_free_size_peak;
+        constinit void *g_heap_buffer;
+        constinit size_t g_heap_size;
+        constinit size_t g_heap_free_size_peak;
 
-        AdditionalDeviceAddressEntry g_additional_device_address_entry;
+        constinit AdditionalDeviceAddressEntry g_additional_device_address_entry;
 
     }
 
diff --git a/libstratosphere/source/fssystem/fssystem_read_only_block_cache_storage.hpp b/libstratosphere/source/fssystem/fssystem_read_only_block_cache_storage.hpp
index f46ee156..61a73d88 100644
--- a/libstratosphere/source/fssystem/fssystem_read_only_block_cache_storage.hpp
+++ b/libstratosphere/source/fssystem/fssystem_read_only_block_cache_storage.hpp
@@ -25,12 +25,12 @@ namespace ams::fssystem {
         private:
             using BlockCache = LruListCache<s64, char *>;
         private:
-            os::Mutex mutex;
+            os::SdkMutex mutex;
             BlockCache block_cache;
             fs::IStorage * const base_storage;
             s32 block_size;
         public:
-            ReadOnlyBlockCacheStorage(IStorage *bs, s32 bsz, char *buf, size_t buf_size, s32 cache_block_count) : mutex(false), base_storage(bs), block_size(bsz) {
+            ReadOnlyBlockCacheStorage(IStorage *bs, s32 bsz, char *buf, size_t buf_size, s32 cache_block_count) : mutex(), base_storage(bs), block_size(bsz) {
                 /* Validate preconditions. */
                 AMS_ASSERT(buf_size >= static_cast<size_t>(this->block_size));
                 AMS_ASSERT(util::IsPowerOfTwo(this->block_size));
diff --git a/libstratosphere/source/fssystem/save/fssystem_block_cache_buffered_storage.cpp b/libstratosphere/source/fssystem/save/fssystem_block_cache_buffered_storage.cpp
index 2379ab20..773840aa 100644
--- a/libstratosphere/source/fssystem/save/fssystem_block_cache_buffered_storage.cpp
+++ b/libstratosphere/source/fssystem/save/fssystem_block_cache_buffered_storage.cpp
@@ -27,7 +27,7 @@ namespace ams::fssystem::save {
         this->Finalize();
     }
 
-    Result BlockCacheBufferedStorage::Initialize(IBufferManager *bm, os::Mutex *mtx, IStorage *data, s64 data_size, size_t verif_block_size, s32 max_cache_entries, bool is_real_data, s8 buffer_level, bool is_keep_burst_mode, fs::StorageType storage_type) {
+    Result BlockCacheBufferedStorage::Initialize(IBufferManager *bm, os::SdkRecursiveMutex *mtx, IStorage *data, s64 data_size, size_t verif_block_size, s32 max_cache_entries, bool is_real_data, s8 buffer_level, bool is_keep_burst_mode, fs::StorageType storage_type) {
         /* Validate preconditions. */
         AMS_ASSERT(data != nullptr);
         AMS_ASSERT(bm   != nullptr);
diff --git a/libstratosphere/source/fssystem/save/fssystem_buffered_storage.cpp b/libstratosphere/source/fssystem/save/fssystem_buffered_storage.cpp
index d8de70fc..bdd064bd 100644
--- a/libstratosphere/source/fssystem/save/fssystem_buffered_storage.cpp
+++ b/libstratosphere/source/fssystem/save/fssystem_buffered_storage.cpp
@@ -582,7 +582,7 @@ namespace ams::fssystem::save {
             }
     };
 
-    BufferedStorage::BufferedStorage() : base_storage(), buffer_manager(), block_size(), base_storage_size(), caches(), cache_count(), next_acquire_cache(), next_fetch_cache(), mutex(false), bulk_read_enabled() {
+    BufferedStorage::BufferedStorage() : base_storage(), buffer_manager(), block_size(), base_storage_size(), caches(), cache_count(), next_acquire_cache(), next_fetch_cache(), mutex(), bulk_read_enabled() {
         /* ... */
     }
 
diff --git a/libstratosphere/source/fssystem/save/fssystem_hierarchical_integrity_verification_storage.cpp b/libstratosphere/source/fssystem/save/fssystem_hierarchical_integrity_verification_storage.cpp
index 24967553..67d9e47e 100644
--- a/libstratosphere/source/fssystem/save/fssystem_hierarchical_integrity_verification_storage.cpp
+++ b/libstratosphere/source/fssystem/save/fssystem_hierarchical_integrity_verification_storage.cpp
@@ -150,7 +150,7 @@ namespace ams::fssystem::save {
         this->storage = fs::SubStorage();
     }
 
-    Result HierarchicalIntegrityVerificationStorage::Initialize(const HierarchicalIntegrityVerificationInformation &info, HierarchicalStorageInformation storage, FileSystemBufferManagerSet *bufs, os::Mutex *mtx, fs::StorageType storage_type) {
+    Result HierarchicalIntegrityVerificationStorage::Initialize(const HierarchicalIntegrityVerificationInformation &info, HierarchicalStorageInformation storage, FileSystemBufferManagerSet *bufs, os::SdkRecursiveMutex *mtx, fs::StorageType storage_type) {
         /* Validate preconditions. */
         AMS_ASSERT(bufs != nullptr);
         AMS_ASSERT(IntegrityMinLayerCount <= info.max_layers && info.max_layers <= IntegrityMaxLayerCount);
diff --git a/libstratosphere/source/hid/hid_api.cpp b/libstratosphere/source/hid/hid_api.cpp
index 7196618b..2257d091 100644
--- a/libstratosphere/source/hid/hid_api.cpp
+++ b/libstratosphere/source/hid/hid_api.cpp
@@ -20,8 +20,8 @@ namespace ams::hid {
     namespace {
 
         /* Global lock. */
-        os::Mutex g_hid_lock(false);
-        bool g_initialized_hid = false;
+        constinit os::SdkMutex g_hid_lock;
+        constinit bool g_initialized_hid = false;
 
         /* Set of supported NpadIds (we want to read from any connected controllers). */
         constexpr const HidNpadIdType NpadIdTypes[] = {
diff --git a/libstratosphere/source/lmem/impl/lmem_impl_common_heap.hpp b/libstratosphere/source/lmem/impl/lmem_impl_common_heap.hpp
index 6c2c5fa9..e39d077d 100644
--- a/libstratosphere/source/lmem/impl/lmem_impl_common_heap.hpp
+++ b/libstratosphere/source/lmem/impl/lmem_impl_common_heap.hpp
@@ -30,13 +30,13 @@ namespace ams::lmem::impl {
         public:
             explicit ScopedHeapLock(HeapHandle h) : handle(h) {
                 if (this->handle->option & CreateOption_ThreadSafe) {
-                    os::LockMutex(std::addressof(this->handle->mutex));
+                    os::LockSdkMutex(std::addressof(this->handle->mutex));
                 }
             }
 
             ~ScopedHeapLock() {
                 if (this->handle->option & CreateOption_ThreadSafe) {
-                    os::UnlockMutex(std::addressof(this->handle->mutex));
+                    os::UnlockSdkMutex(std::addressof(this->handle->mutex));
                 }
             }
     };
diff --git a/libstratosphere/source/lmem/impl/lmem_impl_exp_heap.cpp b/libstratosphere/source/lmem/impl/lmem_impl_exp_heap.cpp
index 213fbd5f..3119a303 100644
--- a/libstratosphere/source/lmem/impl/lmem_impl_exp_heap.cpp
+++ b/libstratosphere/source/lmem/impl/lmem_impl_exp_heap.cpp
@@ -427,6 +427,7 @@ namespace ams::lmem::impl {
         const s32 abs_alignment = std::abs(alignment);
         AMS_ASSERT((abs_alignment & (abs_alignment - 1)) == 0);
         AMS_ASSERT(MinimumAlignment <= static_cast<size_t>(abs_alignment));
+        AMS_UNUSED(abs_alignment);
 
         /* Fix size to be correctly aligned. */
         if (size == 0) {
diff --git a/libstratosphere/source/lmem/lmem_exp_heap.cpp b/libstratosphere/source/lmem/lmem_exp_heap.cpp
index 60604043..489ec955 100644
--- a/libstratosphere/source/lmem/lmem_exp_heap.cpp
+++ b/libstratosphere/source/lmem/lmem_exp_heap.cpp
@@ -21,15 +21,12 @@ namespace ams::lmem {
     HeapHandle CreateExpHeap(void *address, size_t size, u32 option) {
         HeapHandle handle = impl::CreateExpHeap(address, size, option);
         if (option & CreateOption_ThreadSafe) {
-            os::InitializeMutex(std::addressof(handle->mutex), false, 0);
+            os::InitializeSdkMutex(std::addressof(handle->mutex));
         }
         return handle;
     }
 
     void DestroyExpHeap(HeapHandle handle) {
-        if (handle->option & CreateOption_ThreadSafe) {
-            os::FinalizeMutex(std::addressof(handle->mutex));
-        }
         impl::DestroyExpHeap(handle);
     }
 
diff --git a/libstratosphere/source/lmem/lmem_unit_heap.cpp b/libstratosphere/source/lmem/lmem_unit_heap.cpp
index edc7c8cd..5a9b2a58 100644
--- a/libstratosphere/source/lmem/lmem_unit_heap.cpp
+++ b/libstratosphere/source/lmem/lmem_unit_heap.cpp
@@ -21,7 +21,7 @@ namespace ams::lmem {
     HeapHandle CreateUnitHeap(void *address, size_t size, size_t unit_size, u32 option) {
         HeapHandle handle = impl::CreateUnitHeap(address, size, unit_size, DefaultAlignment, static_cast<u16>(option), InfoPlacement_Head, nullptr);
         if (option & CreateOption_ThreadSafe) {
-            os::InitializeMutex(std::addressof(handle->mutex), false, 0);
+            os::InitializeSdkMutex(std::addressof(handle->mutex));
         }
         return handle;
     }
@@ -29,7 +29,7 @@ namespace ams::lmem {
     HeapHandle CreateUnitHeap(void *address, size_t size, size_t unit_size, u32 option, s32 alignment, InfoPlacement info_placement) {
         HeapHandle handle = impl::CreateUnitHeap(address, size, unit_size, alignment, static_cast<u16>(option), info_placement, nullptr);
         if (option & CreateOption_ThreadSafe) {
-            os::InitializeMutex(std::addressof(handle->mutex), false, 0);
+            os::InitializeSdkMutex(std::addressof(handle->mutex));
         }
         return handle;
     }
@@ -37,15 +37,12 @@ namespace ams::lmem {
     HeapHandle CreateUnitHeap(void *address, size_t size, size_t unit_size, u32 option, s32 alignment, HeapCommonHead *heap_head) {
         HeapHandle handle = impl::CreateUnitHeap(address, size, unit_size, alignment, static_cast<u16>(option), InfoPlacement_Head, heap_head);
         if (option & CreateOption_ThreadSafe) {
-            os::InitializeMutex(std::addressof(handle->mutex), false, 0);
+            os::InitializeSdkMutex(std::addressof(handle->mutex));
         }
         return handle;
     }
 
     void DestroyUnitHeap(HeapHandle handle) {
-        if (handle->option & CreateOption_ThreadSafe) {
-            os::FinalizeMutex(std::addressof(handle->mutex));
-        }
         impl::DestroyUnitHeap(handle);
     }
 
diff --git a/libstratosphere/source/mem/impl/heap/mem_impl_heap_tls_heap_central.hpp b/libstratosphere/source/mem/impl/heap/mem_impl_heap_tls_heap_central.hpp
index 327e029b..656b942d 100644
--- a/libstratosphere/source/mem/impl/heap/mem_impl_heap_tls_heap_central.hpp
+++ b/libstratosphere/source/mem/impl/heap/mem_impl_heap_tls_heap_central.hpp
@@ -201,14 +201,14 @@ namespace ams::mem::impl::heap {
             s32 static_thread_quota;
             s32 dynamic_thread_quota;
             bool use_virtual_memory;
-            os::Mutex lock;
+            os::SdkRecursiveMutex lock;
             ListHeader<SpanPage> spanpage_list;
             ListHeader<SpanPage> full_spanpage_list;
             ListHeader<Span> freelists[FreeListCount];
             FreeListAvailableWord freelists_bitmap[NumFreeListBitmaps];
             ListHeader<Span> smallmem_lists[TlsHeapStatic::NumClassInfo];
         public:
-            TlsHeapCentral() : lock(true) {
+            TlsHeapCentral() : lock() {
                 this->span_table.total_pages = 0;
             }
 
diff --git a/libstratosphere/source/ncm/ncm_install_task_base.cpp b/libstratosphere/source/ncm/ncm_install_task_base.cpp
index f9a56b6a..8f23ff1f 100644
--- a/libstratosphere/source/ncm/ncm_install_task_base.cpp
+++ b/libstratosphere/source/ncm/ncm_install_task_base.cpp
@@ -635,7 +635,7 @@ namespace ams::ncm {
         for (s32 i = 0; i < count; i++) {
             R_UNLESS(!this->IsCancelRequested(), ncm::ResultCreatePlaceHolderCancelled());
 
-            static os::Mutex s_placeholder_mutex(false);
+            static constinit os::SdkMutex s_placeholder_mutex;
             std::scoped_lock lk(s_placeholder_mutex);
 
             InstallContentMeta content_meta;
diff --git a/libstratosphere/source/ncm/ncm_placeholder_accessor.hpp b/libstratosphere/source/ncm/ncm_placeholder_accessor.hpp
index 1d808445..72368649 100644
--- a/libstratosphere/source/ncm/ncm_placeholder_accessor.hpp
+++ b/libstratosphere/source/ncm/ncm_placeholder_accessor.hpp
@@ -32,7 +32,7 @@ namespace ams::ncm {
             std::array<CacheEntry, MaxCacheEntries> caches;
             PathString *root_path;
             u64 cur_counter;
-            os::Mutex cache_mutex;
+            os::SdkMutex cache_mutex;
             MakePlaceHolderPathFunction make_placeholder_path_func;
             bool delay_flush;
         private:
@@ -43,7 +43,7 @@ namespace ams::ncm {
             CacheEntry *FindInCache(PlaceHolderId placeholder_id);
             CacheEntry *GetFreeEntry();;
         public:
-            PlaceHolderAccessor() : cur_counter(0), cache_mutex(false), delay_flush(false) {
+            PlaceHolderAccessor() : cur_counter(0), cache_mutex(), delay_flush(false) {
                 for (size_t i = 0; i < MaxCacheEntries; i++) {
                     caches[i].id = InvalidPlaceHolderId;
                 }
diff --git a/libstratosphere/source/patcher/patcher_api.cpp b/libstratosphere/source/patcher/patcher_api.cpp
index 177b80d9..bc827086 100644
--- a/libstratosphere/source/patcher/patcher_api.cpp
+++ b/libstratosphere/source/patcher/patcher_api.cpp
@@ -31,8 +31,8 @@ namespace ams::patcher {
         constexpr size_t ModuleIpsPatchLength = 2 * sizeof(ro::ModuleId) + IpsFileExtensionLength;
 
         /* Global data. */
-        os::Mutex apply_patch_lock(false);
-        u8 g_patch_read_buffer[os::MemoryPageSize];
+        constinit os::SdkMutex g_apply_patch_lock;
+        constinit u8 g_patch_read_buffer[os::MemoryPageSize];
 
         /* Helpers. */
         inline u8 ConvertHexNybble(const char nybble) {
@@ -213,7 +213,7 @@ namespace ams::patcher {
 
     void LocateAndApplyIpsPatchesToModule(const char *mount_name, const char *patch_dir_name, size_t protected_size, size_t offset, const ro::ModuleId *module_id, u8 *mapped_module, size_t mapped_size) {
         /* Ensure only one thread tries to apply patches at a time. */
-        std::scoped_lock lk(apply_patch_lock);
+        std::scoped_lock lk(g_apply_patch_lock);
 
         /* Inspect all patches from /atmosphere/<patch_dir>/<*>/<*>.ips */
         char path[fs::EntryNameLengthMax + 1];
diff --git a/libstratosphere/source/sf/cmif/sf_cmif_domain_manager.cpp b/libstratosphere/source/sf/cmif/sf_cmif_domain_manager.cpp
index 7c16a962..ec310bab 100644
--- a/libstratosphere/source/sf/cmif/sf_cmif_domain_manager.cpp
+++ b/libstratosphere/source/sf/cmif/sf_cmif_domain_manager.cpp
@@ -106,7 +106,7 @@ namespace ams::sf::cmif {
         return entry->object.Clone();
     }
 
-    ServerDomainManager::EntryManager::EntryManager(DomainEntryStorage *entry_storage, size_t entry_count) : lock(false) {
+    ServerDomainManager::EntryManager::EntryManager(DomainEntryStorage *entry_storage, size_t entry_count) : lock() {
         this->entries = reinterpret_cast<Entry *>(entry_storage);
         this->num_entries = entry_count;
         for (size_t i = 0; i < this->num_entries; i++) {
diff --git a/libstratosphere/source/sm/sm_utils.cpp b/libstratosphere/source/sm/sm_utils.cpp
index f241e79e..57dc2383 100644
--- a/libstratosphere/source/sm/sm_utils.cpp
+++ b/libstratosphere/source/sm/sm_utils.cpp
@@ -21,17 +21,17 @@ namespace ams::sm::impl {
     namespace {
 
         /* Globals. */
-        constinit os::Mutex g_mitm_ack_session_mutex(true);
-        constinit os::Mutex g_per_thread_session_mutex(true);
+        constinit os::SdkRecursiveMutex g_mitm_ack_session_mutex;
+        constinit os::SdkRecursiveMutex g_per_thread_session_mutex;
 
     }
 
     /* Utilities. */
-    os::Mutex &GetMitmAcknowledgementSessionMutex() {
+    os::SdkRecursiveMutex &GetMitmAcknowledgementSessionMutex() {
         return g_mitm_ack_session_mutex;
     }
 
-    os::Mutex &GetPerThreadSessionMutex() {
+    os::SdkRecursiveMutex &GetPerThreadSessionMutex() {
         return g_per_thread_session_mutex;
     }
 
diff --git a/libstratosphere/source/sm/sm_utils.hpp b/libstratosphere/source/sm/sm_utils.hpp
index f8926c61..ed1cd132 100644
--- a/libstratosphere/source/sm/sm_utils.hpp
+++ b/libstratosphere/source/sm/sm_utils.hpp
@@ -21,8 +21,8 @@
 namespace ams::sm::impl {
 
     /* Utilities. */
-    os::Mutex &GetMitmAcknowledgementSessionMutex();
-    os::Mutex &GetPerThreadSessionMutex();
+    os::SdkRecursiveMutex &GetMitmAcknowledgementSessionMutex();
+    os::SdkRecursiveMutex &GetPerThreadSessionMutex();
 
     template<typename F>
     Result DoWithMitmAcknowledgementSession(F f) {
diff --git a/libvapours/source/sdmmc/impl/sdmmc_base_device_accessor.hpp b/libvapours/source/sdmmc/impl/sdmmc_base_device_accessor.hpp
index 8cb0490e..5e888674 100644
--- a/libvapours/source/sdmmc/impl/sdmmc_base_device_accessor.hpp
+++ b/libvapours/source/sdmmc/impl/sdmmc_base_device_accessor.hpp
@@ -214,9 +214,9 @@ namespace ams::sdmmc::impl {
             bool is_awake;
         public:
         #if defined(AMS_SDMMC_THREAD_SAFE)
-            mutable os::Mutex device_mutex;
+            mutable os::SdkRecursiveMutex device_mutex;
         public:
-            BaseDevice() : device_mutex(true)
+            BaseDevice() : device_mutex()
         #else
             BaseDevice()
         #endif