Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752443AbcLFJYd (ORCPT ); Tue, 6 Dec 2016 04:24:33 -0500 Received: from mail.skyhub.de ([78.46.96.112]:58493 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751064AbcLFJYa (ORCPT ); Tue, 6 Dec 2016 04:24:30 -0500 Date: Tue, 6 Dec 2016 10:24:24 +0100 From: Borislav Petkov To: Andy Lutomirski Cc: x86@kernel.org, One Thousand Gnomes , "linux-kernel@vger.kernel.org" , Brian Gerst , Matthew Whitehead Subject: Re: [RFC PATCH 4/6] x86/fpu: Fix "x86/fpu: Legacy x87 FPU detected" message Message-ID: <20161206092424.crarepjm2ntkfpd4@pd.tnic> References: <21c7c86831db499b725f70d6603327f4ebcf09cf.1480985979.git.luto@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <21c7c86831db499b725f70d6603327f4ebcf09cf.1480985979.git.luto@kernel.org> User-Agent: NeoMutt/20161014 (1.7.1) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1439 Lines: 47 On Mon, Dec 05, 2016 at 05:01:13PM -0800, Andy Lutomirski wrote: > That message isn't at all clear -- what does "Legacy x87" even > mean? > > Clarify it. If there's no FPU, say "x86/fpu: No FPU detected". If > there's an FPU that doesn't have XSAVE, say "x86/fpu: Pre-XSAVE x87 > FPU detected". > > Signed-off-by: Andy Lutomirski > --- > arch/x86/kernel/fpu/xstate.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c > index 1d7770447b3e..2d592b1c75e4 100644 > --- a/arch/x86/kernel/fpu/xstate.c > +++ b/arch/x86/kernel/fpu/xstate.c > @@ -705,8 +705,13 @@ void __init fpu__init_system_xstate(void) > WARN_ON_FPU(!on_boot_cpu); > on_boot_cpu = 0; > > + if (!boot_cpu_has(X86_FEATURE_FPU)) { > + pr_info("x86/fpu: No FPU detected.\n"); > + return; > + } > + > if (!boot_cpu_has(X86_FEATURE_XSAVE)) { > - pr_info("x86/fpu: Legacy x87 FPU detected.\n"); > + pr_info("x86/fpu: Pre-XSAVE x87 FPU detected.\n"); Well, there's also FXSAVE and FSAVE. The legacy thing kinda made sense to me here. Maybe say something like this: pr_info("x86/fpu: FPU detected: FSAVE|FXSAVE|XSAVE support\n", ... and use X86_FEATURE_XSAVE and X86_FEATURE_FXSR to print the respective *SAVE string...? FSAVE we issue by default. Hmm. -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.