From be7436d519970365775d3d2d7b73e75c233e1994 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Tue, 28 Apr 2015 12:53:45 +0200 Subject: x86/fpu: Clarify ancient comments in fpu__restore() So this function still had ancient language about 'saving current math information' - but we haven't been doing lazy FPU saves for quite some time, we are doing lazy FPU restores. Also remove IRQ13 related comment, which we don't support anymore either. Cc: Andy Lutomirski Cc: Borislav Petkov 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/core.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'arch') diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index 1d6e97c59a72..91b9935021c4 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -319,14 +319,14 @@ static void fpu__activate_stopped(struct fpu *child_fpu) } /* - * 'fpu__restore()' saves the current math information in the - * old math state array, and gets the new ones from the current task + * 'fpu__restore()' is called to copy FPU registers from + * the FPU fpstate to the live hw registers and to activate + * access to the hardware registers, so that FPU instructions + * can be used afterwards. * - * Careful.. There are problems with IBM-designed IRQ13 behaviour. - * Don't touch unless you *really* know how it works. - * - * Must be called with kernel preemption disabled (eg with local - * local interrupts as in the case of do_device_not_available). + * Must be called with kernel preemption disabled (for example + * with local interrupts disabled, as it is in the case of + * do_device_not_available()). */ void fpu__restore(void) { -- cgit v1.2.3