Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752913AbbF2M1d (ORCPT ); Mon, 29 Jun 2015 08:27:33 -0400 Received: from mail-wi0-f178.google.com ([209.85.212.178]:38632 "EHLO mail-wi0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751269AbbF2M11 (ORCPT ); Mon, 29 Jun 2015 08:27:27 -0400 Message-ID: <1435580843.2866.5.camel@gmail.com> Subject: Re: [all better] Re: regression: massive trouble with fpu rework From: Mike Galbraith To: Borislav Petkov Cc: Ingo Molnar , Ingo Molnar , LKML , "H. Peter Anvin" , Thomas Gleixner , Andy Lutomirski , Denys Vlasenko , Oleg Nesterov , Dave Hansen Date: Mon, 29 Jun 2015 14:27:23 +0200 In-Reply-To: <20150629083302.GA13113@pd.tnic> References: <1435386316.3664.23.camel@gmail.com> <1435393129.3490.7.camel@gmail.com> <20150627082514.GA10894@gmail.com> <1435395328.6545.10.camel@gmail.com> <20150629064008.GA16251@gmail.com> <1435566329.2900.1.camel@gmail.com> <20150629083302.GA13113@pd.tnic> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.12.11 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1049 Lines: 29 On Mon, 2015-06-29 at 10:33 +0200, Borislav Petkov wrote: > I bet it is that > > /* Unmask CPUID levels if masked: */ > if (c->x86 > 6 || (c->x86 == 6 && c->x86_model >= 0xd)) { > if (msr_clear_bit(MSR_IA32_MISC_ENABLE, > MSR_IA32_MISC_ENABLE_LIMIT_CPUID_BIT) > 0) { > c->cpuid_level = cpuid_eax(0); > get_cpu_cap(c); > } > } > > in early_init_intel(). If you feel like playing, you might comment it > out to see what happens. With it commented out, and fpu__init_system() either back at previously booting position [5] or at original [0], doesn't matter, box is dead, but differently. It stalls after setting clocksource to tsc, and just sits there. -Mike -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/