x86/fpu: Configure init_fpstate attributes orderly

The init_fpstate setup code is spread out and out of order. The init image
is recorded before its scoped features and the buffer size are determined.

Determine the scope of init_fpstate components and its size before
recording the init state. Also move the relevant code together.

Signed-off-by: Chang S. Bae <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Acked-by: [email protected]
Link: https://lore.kernel.org/r/[email protected]

Author: ChangSeokBae

arch/x86/kernel/fpu/init.c

@@ -210,13 +210,6 @@ static void __init fpu__init_system_xstate_size_legacy(void)
 	fpstate_reset(&current->thread.fpu);
 }
 
-static void __init fpu__init_init_fpstate(void)
-{
-	/* Bring init_fpstate size and features up to date */
-	init_fpstate.size		= fpu_kernel_cfg.max_size;
-	init_fpstate.xfeatures		= fpu_kernel_cfg.max_features;
-}
-
 /*
  * Called on the boot CPU once per system bootup, to set up the initial
  * FPU state that is later cloned into all processes:
@@ -236,5 +229,4 @@ void __init fpu__init_system(struct cpuinfo_x86 *c)
 	fpu__init_system_xstate_size_legacy();
 	fpu__init_system_xstate(fpu_kernel_cfg.max_size);
 	fpu__init_task_struct_size();
-	fpu__init_init_fpstate();
 }

arch/x86/kernel/fpu/xstate.c

@@ -360,7 +360,7 @@ static void __init setup_init_fpu_buf(void)
 
 	print_xstate_features();
 
-	xstate_init_xcomp_bv(&init_fpstate.regs.xsave, fpu_kernel_cfg.max_features);
+	xstate_init_xcomp_bv(&init_fpstate.regs.xsave, init_fpstate.xfeatures);
 
 	/*
 	 * Init all the features state with header.xfeatures being 0x0
@@ -875,6 +875,10 @@ void __init fpu__init_system_xstate(unsigned int legacy_size)
 	update_regset_xstate_info(fpu_user_cfg.max_size,
 				  fpu_user_cfg.max_features);
 
+	/* Bring init_fpstate size and features up to date */
+	init_fpstate.size		= fpu_kernel_cfg.max_size;
+	init_fpstate.xfeatures		= fpu_kernel_cfg.max_features;
+
 	setup_init_fpu_buf();
 
 	/*