diff --git a/repos/ports/src/virtualbox/accloff/sup.cc b/repos/ports/src/virtualbox/accloff/sup.cc
index 58820fb42..003d112ef 100644
--- a/repos/ports/src/virtualbox/accloff/sup.cc
+++ b/repos/ports/src/virtualbox/accloff/sup.cc
@@ -82,7 +82,6 @@ int SUPR3CallVMMR0Ex(PVMR0 pVMR0, VMCPUID idCpu, unsigned
 
 
 bool create_emt_vcpu(pthread_t * thread, size_t stack_size,
-                     const pthread_attr_t *attr,
                      void *(*start_routine)(void *), void *arg,
                      Genode::Cpu_session * cpu_session,
                      Genode::Affinity::Location location,
diff --git a/repos/ports/src/virtualbox/spec/muen/sup.cc b/repos/ports/src/virtualbox/spec/muen/sup.cc
index 39b43f3c3..731b53837 100644
--- a/repos/ports/src/virtualbox/spec/muen/sup.cc
+++ b/repos/ports/src/virtualbox/spec/muen/sup.cc
@@ -697,7 +697,6 @@ int SUPR3CallVMMR0Ex(PVMR0 pVMR0, VMCPUID idCpu, unsigned
 
 
 bool create_emt_vcpu(pthread_t * thread, size_t stack_size,
-                     const pthread_attr_t *attr,
                      void *(*start_routine)(void *), void *arg,
                      Genode::Cpu_session * cpu_session,
                      Genode::Affinity::Location location,
diff --git a/repos/ports/src/virtualbox/spec/nova/sup.cc b/repos/ports/src/virtualbox/spec/nova/sup.cc
index d16792abc..c759f8471 100644
--- a/repos/ports/src/virtualbox/spec/nova/sup.cc
+++ b/repos/ports/src/virtualbox/spec/nova/sup.cc
@@ -286,7 +286,6 @@ void *operator new (__SIZE_TYPE__ size, int log2_align)
 
 
 bool create_emt_vcpu(pthread_t * pthread, size_t stack,
-                     const pthread_attr_t *attr,
                      void *(*start_routine)(void *), void *arg,
                      Genode::Cpu_session * cpu_session,
                      Genode::Affinity::Location location,
@@ -305,13 +304,13 @@ bool create_emt_vcpu(pthread_t * pthread, size_t stack,
 
 	if (vmx)
 		vcpu_handler = new (0x10) Vcpu_handler_vmx(genode_env(),
-		                                           stack, attr, start_routine,
+		                                           stack, start_routine,
 		                                           arg, cpu_session, location,
 		                                           cpu_id, name, pd_vcpus);
 
 	if (svm)
 		vcpu_handler = new (0x10) Vcpu_handler_svm(genode_env(),
-		                                           stack, attr, start_routine,
+		                                           stack, start_routine,
 		                                           arg, cpu_session, location,
 		                                           cpu_id, name, pd_vcpus);
 
diff --git a/repos/ports/src/virtualbox/spec/nova/vcpu.h b/repos/ports/src/virtualbox/spec/nova/vcpu.h
index c1e1c8892..746a11efd 100644
--- a/repos/ports/src/virtualbox/spec/nova/vcpu.h
+++ b/repos/ports/src/virtualbox/spec/nova/vcpu.h
@@ -767,7 +767,7 @@ class Vcpu_handler : public Vmm::Vcpu_dispatcher<Genode::Thread>,
 		};
 
 
-		Vcpu_handler(Genode::Env &env, size_t stack_size, const pthread_attr_t *attr,
+		Vcpu_handler(Genode::Env &env, size_t stack_size,
 		             void *(*start_routine) (void *), void *arg,
 		             Genode::Cpu_session * cpu_session,
 		             Genode::Affinity::Location location,
@@ -776,7 +776,7 @@ class Vcpu_handler : public Vmm::Vcpu_dispatcher<Genode::Thread>,
 		:
 			Vmm::Vcpu_dispatcher<Genode::Thread>(env, stack_size, cpu_session,
 			                                     location, name),
-			_pthread(*this, attr ? *attr : 0),
+			_pthread(*this),
 			_start_routine(start_routine),
 			_start_routine_arg(arg),
 			_vcpu(cpu_session, location, pd_vcpu),
diff --git a/repos/ports/src/virtualbox/spec/nova/vcpu_svm.h b/repos/ports/src/virtualbox/spec/nova/vcpu_svm.h
index 0909c368a..03c4929ca 100644
--- a/repos/ports/src/virtualbox/spec/nova/vcpu_svm.h
+++ b/repos/ports/src/virtualbox/spec/nova/vcpu_svm.h
@@ -94,14 +94,14 @@ class Vcpu_handler_svm : public Vcpu_handler
 
 	public:
 
-		Vcpu_handler_svm(Genode::Env &env, size_t stack_size, const pthread_attr_t *attr,
+		Vcpu_handler_svm(Genode::Env &env, size_t stack_size,
 		                 void *(*start_routine) (void *), void *arg,
 		                 Genode::Cpu_session * cpu_session,
 		                 Genode::Affinity::Location location,
 		                 unsigned int cpu_id, const char * name,
 		                 Genode::Pd_session_capability pd_vcpu)
 		:
-			Vcpu_handler(env, stack_size, attr, start_routine, arg, cpu_session,
+			Vcpu_handler(env, stack_size, start_routine, arg, cpu_session,
 			             location, cpu_id, name, pd_vcpu)
 		{
 			using namespace Nova;
diff --git a/repos/ports/src/virtualbox/spec/nova/vcpu_vmx.h b/repos/ports/src/virtualbox/spec/nova/vcpu_vmx.h
index ec84a92a0..fb0f0da8f 100644
--- a/repos/ports/src/virtualbox/spec/nova/vcpu_vmx.h
+++ b/repos/ports/src/virtualbox/spec/nova/vcpu_vmx.h
@@ -158,14 +158,14 @@ class Vcpu_handler_vmx : public Vcpu_handler
 
 	public:
 
-		Vcpu_handler_vmx(Genode::Env &env, size_t stack_size, const pthread_attr_t *attr,
+		Vcpu_handler_vmx(Genode::Env &env, size_t stack_size,
 		                 void *(*start_routine) (void *), void *arg,
 		                 Genode::Cpu_session * cpu_session,
 		                 Genode::Affinity::Location location,
 		                 unsigned int cpu_id, const char * name,
 		                 Genode::Pd_session_capability pd_vcpu)
 		:
-			 Vcpu_handler(env, stack_size, attr, start_routine, arg, cpu_session, 
+			 Vcpu_handler(env, stack_size, start_routine, arg, cpu_session, 
 			              location, cpu_id, name, pd_vcpu)
 		{
 			using namespace Nova;
diff --git a/repos/ports/src/virtualbox/sup.h b/repos/ports/src/virtualbox/sup.h
index 1a16bb16c..6133c81a7 100644
--- a/repos/ports/src/virtualbox/sup.h
+++ b/repos/ports/src/virtualbox/sup.h
@@ -33,7 +33,6 @@ HRESULT genode_check_memory_config(ComObjPtr<Machine> machine);
  * hardware acceleration support.
  */
 bool create_emt_vcpu(pthread_t * pthread, size_t stack,
-                     const pthread_attr_t *attr,
                      void *(*start_routine)(void *), void *arg,
                      Genode::Cpu_session * cpu_session,
                      Genode::Affinity::Location location,
diff --git a/repos/ports/src/virtualbox/thread.cc b/repos/ports/src/virtualbox/thread.cc
index d810c9f46..f78dbf15d 100644
--- a/repos/ports/src/virtualbox/thread.cc
+++ b/repos/ports/src/virtualbox/thread.cc
@@ -89,7 +89,7 @@ static int create_thread(pthread_t *thread, const pthread_attr_t *attr,
 		Genode::Affinity::Space space = cpu_session->affinity_space();
 		Genode::Affinity::Location location(space.location_of_index(cpu_id));
 
-		if (create_emt_vcpu(thread, stack_size, attr, start_routine, arg,
+		if (create_emt_vcpu(thread, stack_size, start_routine, arg,
 		                    cpu_session, location, cpu_id, rtthread->szName))
 			return 0;
 		/*
@@ -99,10 +99,9 @@ static int create_thread(pthread_t *thread, const pthread_attr_t *attr,
 	}
 
 	pthread_t thread_obj = new (vmm_heap())
-	                           pthread(attr ? *attr : 0, start_routine,
-	                           arg, stack_size, rtthread->szName,
-	                           cpu_connection(rtthread->enmType),
-	                           Genode::Affinity::Location());
+		pthread(start_routine, arg, stack_size, rtthread->szName,
+		        cpu_connection(rtthread->enmType),
+		        Genode::Affinity::Location());
 
 	if (!thread_obj)
 		return EAGAIN;
diff --git a/repos/ports/src/virtualbox5/accloff/sup.cc b/repos/ports/src/virtualbox5/accloff/sup.cc
index 1c3b49a44..45aa8dc30 100644
--- a/repos/ports/src/virtualbox5/accloff/sup.cc
+++ b/repos/ports/src/virtualbox5/accloff/sup.cc
@@ -84,7 +84,6 @@ int SUPR3CallVMMR0Ex(PVMR0 pVMR0, VMCPUID idCpu, unsigned
 
 
 bool create_emt_vcpu(pthread_t * thread, size_t stack_size,
-                     const pthread_attr_t *attr,
                      void *(*start_routine)(void *), void *arg,
                      Genode::Cpu_session * cpu_session,
                      Genode::Affinity::Location location,
diff --git a/repos/ports/src/virtualbox5/spec/nova/sup.cc b/repos/ports/src/virtualbox5/spec/nova/sup.cc
index 89c85584b..93e5c92a6 100644
--- a/repos/ports/src/virtualbox5/spec/nova/sup.cc
+++ b/repos/ports/src/virtualbox5/spec/nova/sup.cc
@@ -772,7 +772,6 @@ void *operator new (__SIZE_TYPE__ size, int log2_align)
 
 
 bool create_emt_vcpu(pthread_t * pthread, ::size_t stack,
-                     const pthread_attr_t *attr,
                      void *(*start_routine)(void *), void *arg,
                      Genode::Cpu_session * cpu_session,
                      Genode::Affinity::Location location,
@@ -791,13 +790,13 @@ bool create_emt_vcpu(pthread_t * pthread, ::size_t stack,
 
 	if (vmx)
 		vcpu_handler = new (0x10) Vcpu_handler_vmx(genode_env(),
-		                                           stack, attr, start_routine,
+		                                           stack, start_routine,
 		                                           arg, cpu_session, location,
 		                                           cpu_id, name, pd_vcpus);
 
 	if (svm)
 		vcpu_handler = new (0x10) Vcpu_handler_svm(genode_env(),
-		                                           stack, attr, start_routine,
+		                                           stack, start_routine,
 		                                           arg, cpu_session, location,
 		                                           cpu_id, name, pd_vcpus);
 
diff --git a/repos/ports/src/virtualbox5/spec/nova/vcpu.h b/repos/ports/src/virtualbox5/spec/nova/vcpu.h
index 8e70c18af..c0a385ce0 100644
--- a/repos/ports/src/virtualbox5/spec/nova/vcpu.h
+++ b/repos/ports/src/virtualbox5/spec/nova/vcpu.h
@@ -788,7 +788,7 @@ class Vcpu_handler : public Vmm::Vcpu_dispatcher<Genode::Thread>,
 		};
 
 
-		Vcpu_handler(Genode::Env &env, size_t stack_size, const pthread_attr_t *attr,
+		Vcpu_handler(Genode::Env &env, size_t stack_size,
 		             pthread::start_routine_t start_routine, void *arg,
 		             Genode::Cpu_session * cpu_session,
 		             Genode::Affinity::Location location,
@@ -797,7 +797,7 @@ class Vcpu_handler : public Vmm::Vcpu_dispatcher<Genode::Thread>,
 		:
 			Vmm::Vcpu_dispatcher<Genode::Thread>(env, stack_size, cpu_session,
 			                                     location, name),
-			_pthread(*this, attr ? *attr : 0),
+			_pthread(*this),
 			_start_routine(start_routine),
 			_start_routine_arg(arg),
 			_vcpu(cpu_session, location, pd_vcpu),
diff --git a/repos/ports/src/virtualbox5/spec/nova/vcpu_svm.h b/repos/ports/src/virtualbox5/spec/nova/vcpu_svm.h
index ae2e5d387..35da7ae28 100644
--- a/repos/ports/src/virtualbox5/spec/nova/vcpu_svm.h
+++ b/repos/ports/src/virtualbox5/spec/nova/vcpu_svm.h
@@ -84,14 +84,14 @@ class Vcpu_handler_svm : public Vcpu_handler
 
 	public:
 
-		Vcpu_handler_svm(Genode::Env &env, size_t stack_size, const pthread_attr_t *attr,
+		Vcpu_handler_svm(Genode::Env &env, size_t stack_size,
 		                 void *(*start_routine) (void *), void *arg,
 		                 Genode::Cpu_session * cpu_session,
 		                 Genode::Affinity::Location location,
 		                 unsigned int cpu_id, const char * name,
 		                 Genode::Pd_session_capability pd_vcpu)
 		:
-			Vcpu_handler(env, stack_size, attr, start_routine, arg, cpu_session,
+			Vcpu_handler(env, stack_size, start_routine, arg, cpu_session,
 			             location, cpu_id, name, pd_vcpu)
 		{
 			using namespace Nova;
diff --git a/repos/ports/src/virtualbox5/spec/nova/vcpu_vmx.h b/repos/ports/src/virtualbox5/spec/nova/vcpu_vmx.h
index c50db549d..9e25b244c 100644
--- a/repos/ports/src/virtualbox5/spec/nova/vcpu_vmx.h
+++ b/repos/ports/src/virtualbox5/spec/nova/vcpu_vmx.h
@@ -169,14 +169,14 @@ class Vcpu_handler_vmx : public Vcpu_handler
 
 	public:
 
-		Vcpu_handler_vmx(Genode::Env &env, size_t stack_size, const pthread_attr_t *attr,
+		Vcpu_handler_vmx(Genode::Env &env, size_t stack_size,
 		                 void *(*start_routine) (void *), void *arg,
 		                 Genode::Cpu_session * cpu_session,
 		                 Genode::Affinity::Location location,
 		                 unsigned int cpu_id, const char * name,
 		                 Genode::Pd_session_capability pd_vcpu)
 		:
-			 Vcpu_handler(env, stack_size, attr, start_routine, arg, cpu_session, 
+			 Vcpu_handler(env, stack_size, start_routine, arg, cpu_session,
 			              location, cpu_id, name, pd_vcpu)
 		{
 			using namespace Nova;