From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759593Ab3K0BWR (ORCPT ); Tue, 26 Nov 2013 20:22:17 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:39506 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758752Ab3K0A7R (ORCPT ); Tue, 26 Nov 2013 19:59:17 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Fenghua Yu , Ingo Molnar Subject: [PATCH 3.12 074/116] x86/apic: Disable I/O APIC before shutdown of the local APIC Date: Tue, 26 Nov 2013 16:57:27 -0800 Message-Id: <20131127005742.043620644@linuxfoundation.org> X-Mailer: git-send-email 1.8.5.rc3 In-Reply-To: <20131127005736.915454872@linuxfoundation.org> References: <20131127005736.915454872@linuxfoundation.org> User-Agent: quilt/0.60-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Fenghua Yu commit 522e66464467543c0d88d023336eec4df03ad40b upstream. In reboot and crash path, when we shut down the local APIC, the I/O APIC is still active. This may cause issues because external interrupts can still come in and disturb the local APIC during shutdown process. To quiet external interrupts, disable I/O APIC before shutdown local APIC. Signed-off-by: Fenghua Yu Link: http://lkml.kernel.org/r/1382578212-4677-1-git-send-email-fenghua.yu@intel.com [ I suppose the 'issue' is a hang during shutdown. It's a fine change nevertheless. ] Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/crash.c | 2 +- arch/x86/kernel/reboot.c | 8 ++++---- 2 files changed, 5 insertions(+), 5 deletions(-) --- a/arch/x86/kernel/crash.c +++ b/arch/x86/kernel/crash.c @@ -127,12 +127,12 @@ void native_machine_crash_shutdown(struc cpu_emergency_vmxoff(); cpu_emergency_svm_disable(); - lapic_shutdown(); #ifdef CONFIG_X86_IO_APIC /* Prevent crash_kexec() from deadlocking on ioapic_lock. */ ioapic_zap_locks(); disable_IO_APIC(); #endif + lapic_shutdown(); #ifdef CONFIG_HPET_TIMER hpet_disable(); #endif --- a/arch/x86/kernel/reboot.c +++ b/arch/x86/kernel/reboot.c @@ -550,6 +550,10 @@ static void native_machine_emergency_res void native_machine_shutdown(void) { /* Stop the cpus and apics */ +#ifdef CONFIG_X86_IO_APIC + disable_IO_APIC(); +#endif + #ifdef CONFIG_SMP /* * Stop all of the others. Also disable the local irq to @@ -562,10 +566,6 @@ void native_machine_shutdown(void) lapic_shutdown(); -#ifdef CONFIG_X86_IO_APIC - disable_IO_APIC(); -#endif - #ifdef CONFIG_HPET_TIMER hpet_disable(); #endif