diff --git a/src/system/boot/platform/bios_ia32/long_asm.S b/src/system/boot/platform/bios_ia32/long_asm.S
index 8c07f391ec..72b30c26cf 100644
--- a/src/system/boot/platform/bios_ia32/long_asm.S
+++ b/src/system/boot/platform/bios_ia32/long_asm.S
@@ -65,6 +65,7 @@ FUNCTION(long_enter_kernel):
 	// Set data segments.
 	mov		$KERNEL_DATA_SEG, %ax
 	mov		%ax, %ss
+	xor		%ax, %ax
 	mov		%ax, %ds
 	mov		%ax, %es
 	mov		%ax, %fs
diff --git a/src/system/kernel/arch/x86/32/thread.cpp b/src/system/kernel/arch/x86/32/thread.cpp
index 4df16852d7..71b484c370 100644
--- a/src/system/kernel/arch/x86/32/thread.cpp
+++ b/src/system/kernel/arch/x86/32/thread.cpp
@@ -172,29 +172,6 @@ arch_thread_init_kthread_stack(Thread* thread, void* _stack, void* _stackTop,
 }
 
 
-/*!	Initializes the user-space TLS local storage pointer in
-	the thread structure, and the reserved TLS slots.
-	
-	Is called from _create_user_thread_kentry().
-*/
-status_t
-arch_thread_init_tls(Thread *thread)
-{
-	uint32 tls[TLS_USER_THREAD_SLOT + 1];
-
-	thread->user_local_storage = thread->user_stack_base
-		+ thread->user_stack_size;
-
-	// initialize default TLS fields
-	memset(tls, 0, sizeof(tls));
-	tls[TLS_BASE_ADDRESS_SLOT] = thread->user_local_storage;
-	tls[TLS_THREAD_ID_SLOT] = thread->id;
-	tls[TLS_USER_THREAD_SLOT] = (addr_t)thread->user_thread;
-
-	return user_memcpy((void *)thread->user_local_storage, tls, sizeof(tls));
-}
-
-
 void
 arch_thread_dump_info(void *info)
 {
diff --git a/src/system/kernel/arch/x86/64/thread.cpp b/src/system/kernel/arch/x86/64/thread.cpp
index 1d0434fde0..51f4676e82 100644
--- a/src/system/kernel/arch/x86/64/thread.cpp
+++ b/src/system/kernel/arch/x86/64/thread.cpp
@@ -52,7 +52,8 @@ x86_restart_syscall(iframe* frame)
 void
 x86_set_tls_context(Thread* thread)
 {
-
+	// Set FS segment base address to the TLS segment.
+	x86_write_msr(IA32_MSR_FS_BASE, thread->user_local_storage);
 }
 
 
@@ -127,19 +128,6 @@ arch_thread_init_kthread_stack(Thread* thread, void* _stack, void* _stackTop,
 }
 
 
-/*!	Initializes the user-space TLS local storage pointer in
-	the thread structure, and the reserved TLS slots.
-	
-	Is called from _create_user_thread_kentry().
-*/
-status_t
-arch_thread_init_tls(Thread* thread)
-{
-	dprintf("arch_thread_init_tls: TODO\n");
-	return B_OK;
-}
-
-
 void
 arch_thread_dump_info(void* info)
 {
diff --git a/src/system/kernel/arch/x86/arch_thread.cpp b/src/system/kernel/arch/x86/arch_thread.cpp
index 401f9d42dc..8b17b1d015 100644
--- a/src/system/kernel/arch/x86/arch_thread.cpp
+++ b/src/system/kernel/arch/x86/arch_thread.cpp
@@ -18,6 +18,7 @@
 #include <int.h>
 #include <team.h>
 #include <thread.h>
+#include <tls.h>
 #include <vm/vm_types.h>
 #include <vm/VMAddressSpace.h>
 
@@ -198,6 +199,29 @@ arch_team_init_team_struct(Team* p, bool kernel)
 }
 
 
+/*!	Initializes the user-space TLS local storage pointer in
+	the thread structure, and the reserved TLS slots.
+	
+	Is called from _create_user_thread_kentry().
+*/
+status_t
+arch_thread_init_tls(Thread* thread)
+{
+	size_t tls[TLS_USER_THREAD_SLOT + 1];
+
+	thread->user_local_storage = thread->user_stack_base
+		+ thread->user_stack_size;
+
+	// initialize default TLS fields
+	memset(tls, 0, sizeof(tls));
+	tls[TLS_BASE_ADDRESS_SLOT] = thread->user_local_storage;
+	tls[TLS_THREAD_ID_SLOT] = thread->id;
+	tls[TLS_USER_THREAD_SLOT] = (addr_t)thread->user_thread;
+
+	return user_memcpy((void*)thread->user_local_storage, tls, sizeof(tls));
+}
+
+
 void
 arch_thread_context_switch(Thread* from, Thread* to)
 {
diff --git a/src/system/libroot/os/arch/x86_64/thread.cpp b/src/system/libroot/os/arch/x86_64/thread.cpp
index 7b12f02e39..10614ba6c6 100644
--- a/src/system/libroot/os/arch/x86_64/thread.cpp
+++ b/src/system/libroot/os/arch/x86_64/thread.cpp
@@ -11,8 +11,12 @@
 thread_id
 find_thread(const char* name)
 {
-	// TODO x86_64: x86 is doing some TLS thing here. Should that be done here
-	// too?
+	if (!name) {
+		thread_id thread;
+		__asm__ __volatile__ ("movq %%fs:8, %%rax" : "=a" (thread));
+		return thread;
+	}
+
 	return _kern_find_thread(name);
 }
 
diff --git a/src/system/libroot/os/arch/x86_64/tls.cpp b/src/system/libroot/os/arch/x86_64/tls.cpp
index c45b7f7e59..733dc7b2e3 100644
--- a/src/system/libroot/os/arch/x86_64/tls.cpp
+++ b/src/system/libroot/os/arch/x86_64/tls.cpp
@@ -4,10 +4,6 @@
  */
 
 
-// TODO x86_64.
-// Also want to add inline versions to support/TLS.h.
-
-
 #ifndef _NO_INLINE_ASM
 #	define _NO_INLINE_ASM 1
 #endif
@@ -19,7 +15,6 @@
 
 
 static int32 gNextSlot = TLS_FIRST_FREE_SLOT;
-static void* gSlots[TLS_MAX_KEYS];
 
 
 int32
@@ -34,21 +29,37 @@ tls_allocate(void)
 
 
 void*
-tls_get(int32 index)
+tls_get(int32 _index)
 {
-	return gSlots[index];
+	int64 index = _index;
+	void* ret;
+
+	__asm__ __volatile__ (
+		"movq	%%fs:(, %%rdi, 8), %%rax"
+		: "=a" (ret) : "D" (index));
+	return ret;
 }
 
 
 void**
-tls_address(int32 index)
+tls_address(int32 _index)
 {
-	return &gSlots[index];
+	int64 index = _index;
+	void** ret;
+
+	__asm__ __volatile__ (
+		"movq	%%fs:0, %%rax\n\t"
+		"leaq	(%%rax, %%rdi, 8), %%rax\n\t"
+		: "=a" (ret) : "D" (index));
+	return ret;
 }
 
 
 void
-tls_set(int32 index, void* value)
+tls_set(int32 _index, void* value)
 {
-	gSlots[index] = value;
+	int64 index = _index;
+	__asm__ __volatile__ (
+		"movq	%%rsi, %%fs:(, %%rdi, 8)"
+		: : "D" (index), "S" (value));
 }