linux-kernel - [tip:x86/asm] x86/fpu: Remove check

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Date:	Wed, 13 Apr 2016 04:42:34 -0700
From:	tip-bot for Borislav Petkov <tipbot@...or.com>
To:	linux-tip-commits@...r.kernel.org
Cc:	bp@...e.de, brgerst@...il.com, dvlasenk@...hat.com,
	linux-kernel@...r.kernel.org, tglx@...utronix.de, mingo@...nel.org,
	hpa@...or.com, bp@...en8.de, luto@...capital.net,
	peterz@...radead.org, torvalds@...ux-foundation.org
Subject: [tip:x86/asm] x86/fpu: Remove check_fpu() indirection

Commit-ID:  de82fbc3823b7b15ee03466ebfb1c5ec7cc1a941
Gitweb:     http://git.kernel.org/tip/de82fbc3823b7b15ee03466ebfb1c5ec7cc1a941
Author:     Borislav Petkov <bp@...e.de>
AuthorDate: Tue, 5 Apr 2016 08:29:54 +0200
Committer:  Ingo Molnar <mingo@...nel.org>
CommitDate: Wed, 13 Apr 2016 11:37:43 +0200

x86/fpu: Remove check_fpu() indirection

Rename it to fpu__init_check_bugs() and do the CPU feature check at
entry, thus getting rid of the old fpu__init_check_bugs() wrapper.

Signed-off-by: Borislav Petkov <bp@...e.de>
Cc: Andy Lutomirski <luto@...capital.net>
Cc: Borislav Petkov <bp@...en8.de>
Cc: Brian Gerst <brgerst@...il.com>
Cc: Denys Vlasenko <dvlasenk@...hat.com>
Cc: H. Peter Anvin <hpa@...or.com>
Cc: Linus Torvalds <torvalds@...ux-foundation.org>
Cc: Peter Zijlstra <peterz@...radead.org>
Cc: Thomas Gleixner <tglx@...utronix.de>
Link: http://lkml.kernel.org/r/1459837795-2588-6-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@...nel.org>
---
 arch/x86/kernel/fpu/bugs.c | 16 +++++-----------
 1 file changed, 5 insertions(+), 11 deletions(-)

diff --git a/arch/x86/kernel/fpu/bugs.c b/arch/x86/kernel/fpu/bugs.c
index 224b5ec..aad34aa 100644
--- a/arch/x86/kernel/fpu/bugs.c
+++ b/arch/x86/kernel/fpu/bugs.c
@@ -21,11 +21,15 @@ static double __initdata y = 3145727.0;
  * We should really only care about bugs here
  * anyway. Not features.
  */
-static void __init check_fpu(void)
+void __init fpu__init_check_bugs(void)
 {
 	u32 cr0_saved;
 	s32 fdiv_bug;
 
+	/* kernel_fpu_begin/end() relies on patched alternative instructions. */
+	if (!boot_cpu_has(X86_FEATURE_FPU))
+		return;
+
 	/* We might have CR0::TS set already, clear it: */
 	cr0_saved = read_cr0();
 	write_cr0(cr0_saved & ~X86_CR0_TS);
@@ -59,13 +63,3 @@ static void __init check_fpu(void)
 		pr_warn("Hmm, FPU with FDIV bug\n");
 	}
 }
-
-void __init fpu__init_check_bugs(void)
-{
-	/*
-	 * kernel_fpu_begin/end() in check_fpu() relies on the patched
-	 * alternative instructions.
-	 */
-	if (boot_cpu_has(X86_FEATURE_FPU))
-		check_fpu();
-}