x86/fpu: Rename sanitize_i387_state() to fpstate_sanitize_xstate()

So the sanitize_i387_state() function has the following purpose:
on CPUs that support optimized xstate saving instructions, an
FPU fpstate might end up having partially uninitialized data.

This function initializes that data.

Note that the function name is a misnomer and confusing on two levels,
not only is it not i387 specific at all, but it is the exact opposite:
it only matters on xstate CPUs.

So rename sanitize_i387_state() and __sanitize_i387_state() to
fpstate_sanitize_xstate() and __fpstate_sanitize_xstate(),
to clearly express the purpose and usage of the function.

We'll further clean up this function in the next patch.

Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
index c087f2d0f2d1..fc2ff1239fea 100644
--- a/arch/x86/kernel/fpu/xstate.c
+++ b/arch/x86/kernel/fpu/xstate.c
@@ -92,7 +92,7 @@ EXPORT_SYMBOL_GPL(cpu_has_xfeatures);
  * if the corresponding header bit is zero. This is to ensure that user-space doesn't
  * see some stale state in the memory layout during signal handling, debugging etc.
  */
-void __sanitize_i387_state(struct task_struct *tsk)
+void __fpstate_sanitize_xstate(struct task_struct *tsk)
 {
 	struct i387_fxsave_struct *fx = &tsk->thread.fpu.state.fxsave;
 	int feature_bit;
@@ -318,7 +318,7 @@ int save_xstate_sig(void __user *buf, void __user *buf_fx, int size)
 		if (ia32_fxstate)
 			fpu_fxsave(&tsk->thread.fpu);
 	} else {
-		sanitize_i387_state(tsk);
+		fpstate_sanitize_xstate(tsk);
 		if (__copy_to_user(buf_fx, xsave, xstate_size))
 			return -1;
 	}