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 <chang.seok.bae@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: neelnatu@google.com
Link: https://lore.kernel.org/r/20220824191223.1248-2-chang.seok.bae@intel.com

diff --git a/arch/x86/kernel/fpu/init.c b/arch/x86/kernel/fpu/init.c
index 621f4b6..8946f89 100644 (file)
--- a/arch/x86/kernel/fpu/init.c
+++ b/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();
 }

diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
index c834015..f0ce106 100644 (file)
--- a/arch/x86/kernel/fpu/xstate.c
+++ b/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();
 
        /*