From 36fd4f0249f8cb445835acb7c6937a0ffa2b5f14 Mon Sep 17 00:00:00 2001 From: Andy Lutomirski Date: Mon, 31 Oct 2016 15:18:42 -0700 Subject: [PATCH] x86/fpu: Get rid of two redundant clts() calls CR0.TS is cleared by a direct CR0 write in fpu__init_cpu_generic(). We don't need to call clts() two more times right after that. Signed-off-by: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: Denys Vlasenko Cc: Fenghua Yu Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Paolo Bonzini Cc: Peter Zijlstra Cc: Quentin Casasnovas Cc: Rik van Riel Cc: Rusty Russell Cc: Thomas Gleixner Cc: kvm list Link: http://lkml.kernel.org/r/476d2d5066eda24838853426ea74c94140b50c85.1477951965.git.luto@kernel.org Signed-off-by: Ingo Molnar --- arch/x86/kernel/fpu/init.c | 18 ------------------ 1 file changed, 18 deletions(-) diff --git a/arch/x86/kernel/fpu/init.c b/arch/x86/kernel/fpu/init.c index 1a09d133c801..60dece392b3a 100644 --- a/arch/x86/kernel/fpu/init.c +++ b/arch/x86/kernel/fpu/init.c @@ -9,15 +9,6 @@ #include #include -/* - * Initialize the TS bit in CR0 according to the style of context-switches - * we are using: - */ -static void fpu__init_cpu_ctx_switch(void) -{ - clts(); -} - /* * Initialize the registers found in all CPUs, CR0 and CR4: */ @@ -55,7 +46,6 @@ void fpu__init_cpu(void) { fpu__init_cpu_generic(); fpu__init_cpu_xstate(); - fpu__init_cpu_ctx_switch(); } /* @@ -290,14 +280,6 @@ void __init fpu__init_system(struct cpuinfo_x86 *c) */ fpu__init_cpu(); - /* - * But don't leave CR0::TS set yet, as some of the FPU setup - * methods depend on being able to execute FPU instructions - * that will fault on a set TS, such as the FXSAVE in - * fpu__init_system_mxcsr(). - */ - clts(); - fpu__init_system_generic(); fpu__init_system_xstate_size_legacy(); fpu__init_system_xstate(); -- 2.39.5