From f25ad76d92176f41a543a812972e9937ce4f7d08 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Tue, 1 Aug 2023 16:36:25 +0200 Subject: [PATCH] x86/fpu: Move FPU initialization into arch_cpu_finalize_init() commit b81fac906a8f9e682e513ddd95697ec7a20878d4 upstream Initializing the FPU during the early boot process is a pointless exercise. Early boot is convoluted and fragile enough. Nothing requires that the FPU is set up early. It has to be initialized before fork_init() because the task_struct size depends on the FPU register buffer size. Move the initialization to arch_cpu_finalize_init() which is the perfect place to do so. No functional change. This allows to remove quite some of the custom early command line parsing, but that's subject to the next installment. Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20230613224545.902376621@linutronix.de Signed-off-by: Daniel Sneddon Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/cpu/common.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 6f7310e..2bab14d 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1575,8 +1575,6 @@ static void __init early_identify_cpu(struct cpuinfo_x86 *c) sld_setup(c); - fpu__init_system(); - #ifdef CONFIG_X86_32 /* * Regardless of whether PCID is enumerated, the SDM says @@ -2292,8 +2290,6 @@ void cpu_init(void) doublefault_init_cpu_tss(); - fpu__init_cpu(); - if (is_uv_system()) uv_cpu_init(); @@ -2309,6 +2305,7 @@ void cpu_init_secondary(void) */ cpu_init_exception_handling(); cpu_init(); + fpu__init_cpu(); } #endif @@ -2403,6 +2400,13 @@ void __init arch_cpu_finalize_init(void) '0' + (boot_cpu_data.x86 > 6 ? 6 : boot_cpu_data.x86); } + /* + * Must be before alternatives because it might set or clear + * feature bits. + */ + fpu__init_system(); + fpu__init_cpu(); + alternative_instructions(); if (IS_ENABLED(CONFIG_X86_64)) { -- 2.7.4