From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755419AbbHYIO2 (ORCPT ); Tue, 25 Aug 2015 04:14:28 -0400 Received: from www.linutronix.de ([62.245.132.108]:49902 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750863AbbHYIOZ (ORCPT ); Tue, 25 Aug 2015 04:14:25 -0400 Date: Tue, 25 Aug 2015 10:13:55 +0200 (CEST) From: Thomas Gleixner To: Linus Torvalds cc: LKML , Andrew Morton , Ingo Molnar , "H. Peter Anvin" Subject: [GIT pull] x86 fix for 4.2 Message-ID: User-Agent: Alpine 2.11 (DEB 23 2013-08-11) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Linus, please pull the latest x86-urgent-for-linus git tree from: git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86-urgent-for-linus A single fix for a APIC regression introduced in 4.0 which went undetected until now. I screwed up the x2apic cleanup in a subtle way. The screwup is only visible on systems which have x2apic preenabled in the BIOS and need to disable it during boot. Thanks, tglx ------------------> Thomas Gleixner (1): x86/apic: Fix fallout from x2apic cleanup arch/x86/kernel/apic/apic.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c index dcb52850a28f..cde732c1b495 100644 --- a/arch/x86/kernel/apic/apic.c +++ b/arch/x86/kernel/apic/apic.c @@ -1424,7 +1424,7 @@ static inline void __x2apic_disable(void) { u64 msr; - if (cpu_has_apic) + if (!cpu_has_apic) return; rdmsrl(MSR_IA32_APICBASE, msr); @@ -1483,10 +1483,13 @@ void x2apic_setup(void) static __init void x2apic_disable(void) { - u32 x2apic_id; + u32 x2apic_id, state = x2apic_state; - if (x2apic_state != X2APIC_ON) - goto out; + x2apic_mode = 0; + x2apic_state = X2APIC_DISABLED; + + if (state != X2APIC_ON) + return; x2apic_id = read_apic_id(); if (x2apic_id >= 255) @@ -1494,9 +1497,6 @@ static __init void x2apic_disable(void) __x2apic_disable(); register_lapic_address(mp_lapic_addr); -out: - x2apic_state = X2APIC_DISABLED; - x2apic_mode = 0; } static __init void x2apic_enable(void)