From c0841e34fd9bbcef58c537151de8c83d2c910099 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Fri, 24 Apr 2015 03:18:28 +0200 Subject: [PATCH] x86/fpu: Remove xsave_init() __init obfuscation So this code surprised me - and being surprised when reading FPU code does not help maintainability of an already overly complex subsystem. Remove the obfuscation and just don't use __init annotation for now. Anyone who wants to free these ~600 bytes of xstate_enable_boot_cpu() should implement it cleanly. Reviewed-by: Borislav Petkov Cc: Andy Lutomirski Cc: Dave Hansen Cc: Fenghua Yu Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Thomas Gleixner Signed-off-by: Ingo Molnar --- arch/x86/kernel/fpu/xsave.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/arch/x86/kernel/fpu/xsave.c b/arch/x86/kernel/fpu/xsave.c index 4ff726e4e29b..6c1cbb2487fe 100644 --- a/arch/x86/kernel/fpu/xsave.c +++ b/arch/x86/kernel/fpu/xsave.c @@ -606,8 +606,11 @@ static void __init init_xstate_size(void) /* * Enable and initialize the xsave feature. + * + * ( Not marked __init because of false positive section warnings + * generated by xsave_init(). ) */ -static void __init xstate_enable_boot_cpu(void) +static void /* __init */ xstate_enable_boot_cpu(void) { unsigned int eax, ebx, ecx, edx; @@ -663,21 +666,20 @@ static void __init xstate_enable_boot_cpu(void) /* * For the very first instance, this calls xstate_enable_boot_cpu(); * for all subsequent instances, this calls xstate_enable(). - * - * This is somewhat obfuscated due to the lack of powerful enough - * overrides for the section checks. */ void xsave_init(void) { - static __refdata void (*next_func)(void) = xstate_enable_boot_cpu; - void (*this_func)(void); + static char on_boot_cpu = 1; if (!cpu_has_xsave) return; - this_func = next_func; - next_func = xstate_enable; - this_func(); + if (on_boot_cpu) { + on_boot_cpu = 0; + xstate_enable_boot_cpu(); + } else { + xstate_enable(); + } } /* -- 2.20.1