linux-kernel - [PATCH 120/208] x86/fpu: Move !FPU check ingo fpu__init_system_early

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Date:	Tue,  5 May 2015 19:50:12 +0200
From:	Ingo Molnar <mingo@...nel.org>
To:	linux-kernel@...r.kernel.org
Cc:	Andy Lutomirski <luto@...capital.net>,
	Borislav Petkov <bp@...en8.de>,
	Dave Hansen <dave.hansen@...ux.intel.com>,
	Fenghua Yu <fenghua.yu@...el.com>,
	"H. Peter Anvin" <hpa@...or.com>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Oleg Nesterov <oleg@...hat.com>,
	Thomas Gleixner <tglx@...utronix.de>
Subject: [PATCH 120/208] x86/fpu: Move !FPU check ingo fpu__init_system_early_generic()

There's a !FPU related sanity check in fpu__init_cpu_generic(),
which is executed on every CPU onlining - even though we should do
this only once, and during system init.

Move this check to fpu__init_system_early_generic().

Reviewed-by: Borislav Petkov <bp@...en8.de>
Cc: Andy Lutomirski <luto@...capital.net>
Cc: Dave Hansen <dave.hansen@...ux.intel.com>
Cc: Fenghua Yu <fenghua.yu@...el.com>
Cc: H. Peter Anvin <hpa@...or.com>
Cc: Linus Torvalds <torvalds@...ux-foundation.org>
Cc: Oleg Nesterov <oleg@...hat.com>
Cc: Thomas Gleixner <tglx@...utronix.de>
Signed-off-by: Ingo Molnar <mingo@...nel.org>
---
 arch/x86/kernel/fpu/init.c | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kernel/fpu/init.c b/arch/x86/kernel/fpu/init.c
index 3637c509956d..69cdadd49ddf 100644
--- a/arch/x86/kernel/fpu/init.c
+++ b/arch/x86/kernel/fpu/init.c
@@ -85,6 +85,15 @@ static void fpu__init_system_early_generic(struct cpuinfo_x86 *c)
 		set_cpu_cap(c, X86_FEATURE_FPU);
 	else
 		clear_cpu_cap(c, X86_FEATURE_FPU);
+
+#ifndef CONFIG_MATH_EMULATION
+	if (!cpu_has_fpu) {
+		pr_emerg("No FPU found and no math emulation present\n");
+		pr_emerg("Giving up\n");
+		for (;;)
+			asm volatile("hlt");
+	}
+#endif
 }
 
 /*
@@ -180,14 +189,6 @@ static void fpu__init_cpu_generic(void)
 	unsigned long cr0;
 	unsigned long cr4_mask = 0;
 
-#ifndef CONFIG_MATH_EMULATION
-	if (!cpu_has_fpu) {
-		pr_emerg("No FPU found and no math emulation present\n");
-		pr_emerg("Giving up\n");
-		for (;;)
-			asm volatile("hlt");
-	}
-#endif
 	if (cpu_has_fxsr)
 		cr4_mask |= X86_CR4_OSFXSR;
 	if (cpu_has_xmm)
-- 
2.1.0

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