2 files changed, 19 insertions, 21 deletions

diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c
index 2bba7df..adb346b 100644
--- a/arch/s390/kernel/process.c
+++ b/arch/s390/kernel/process.c
@@ -37,9 +37,6 @@
 
 asmlinkage void ret_from_fork(void) asm ("ret_from_fork");
 
-/* FPU save area for the init task */
-__vector128 init_task_fpu_regs[__NUM_VXRS] __init_task_data;
-
 /*
  * Return saved PC of a blocked thread. used in kernel/sched.
  * resume in entry.S does not create a new stack frame, it
@@ -85,35 +82,19 @@ void release_thread(struct task_struct *dead_task)
 
 void arch_release_task_struct(struct task_struct *tsk)
 {
-	/* Free either the floating-point or the vector register save area */
-	kfree(tsk->thread.fpu.regs);
 }
 
 int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
 {
-	size_t fpu_regs_size;
-
-	*dst = *src;
-
-	/*
-	 * If the vector extension is available, it is enabled for all tasks,
-	 * and, thus, the FPU register save area must be allocated accordingly.
-	 */
-	fpu_regs_size = MACHINE_HAS_VX ? sizeof(__vector128) * __NUM_VXRS
-				       : sizeof(freg_t) * __NUM_FPRS;
-	dst->thread.fpu.regs = kzalloc(fpu_regs_size, GFP_KERNEL|__GFP_REPEAT);
-	if (!dst->thread.fpu.regs)
-		return -ENOMEM;
-
 	/*
 	 * Save the floating-point or vector register state of the current
 	 * task and set the CIF_FPU flag to lazy restore the FPU register
 	 * state when returning to user space.
 	 */
 	save_fpu_regs();
-	dst->thread.fpu.fpc = current->thread.fpu.fpc;
-	memcpy(dst->thread.fpu.regs, current->thread.fpu.regs, fpu_regs_size);
 
+	memcpy(dst, src, arch_task_struct_size);
+	dst->thread.fpu.regs = dst->thread.fpu.fprs;
 	return 0;
 }
 
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index d3f9688..f319391 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -809,6 +809,22 @@ static void __init setup_randomness(void)
 }
 
 /*
+ * Find the correct size for the task_struct. This depends on
+ * the size of the struct fpu at the end of the thread_struct
+ * which is embedded in the task_struct.
+ */
+static void __init setup_task_size(void)
+{
+	int task_size = sizeof(struct task_struct);
+
+	if (!MACHINE_HAS_VX) {
+		task_size -= sizeof(__vector128) * __NUM_VXRS;
+		task_size += sizeof(freg_t) * __NUM_FPRS;
+	}
+	arch_task_struct_size = task_size;
+}
+
+/*
  * Setup function called from init/main.c just after the banner
  * was printed.
  */
@@ -846,6 +862,7 @@ void __init setup_arch(char **cmdline_p)
 
 	os_info_init();
 	setup_ipl();
+	setup_task_size();
 
 	/* Do some memory reservations *before* memory is added to memblock */
 	reserve_memory_end();