From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757845Ab2JKAGL (ORCPT ); Wed, 10 Oct 2012 20:06:11 -0400 Received: from mga09.intel.com ([134.134.136.24]:55812 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757677Ab2JKAGJ (ORCPT ); Wed, 10 Oct 2012 20:06:09 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.80,567,1344236400"; d="scan'208";a="204113841" Subject: RE: [PATCH] fix x2apic defect that Linux kernel doesn't mask 8259A interrupt during the time window between changing VT-d table base address and initializing these VT-d entries(smpboot.c and apic.c ) From: Suresh Siddha Reply-To: Suresh Siddha To: "Zhang, Lin-Bao (Linux Kernel R&D)" Cc: "linux-kernel@vger.kernel.org" , "alan@lxorguk.ukuu.org.uk" , "mingo@redhat.com" , "Croxon, Nigel" , "tglx@linutronix.de" , "hpa@zytor.com" , "x86@kernel.org" , "a.p.zijlstra@chello.nl" , "Sakkinen, Jarkko" , "joerg.roedel@amd.com" , "agordeev@redhat.com" , "yinghai@kernel.org" , "stable@kernel.org" Date: Wed, 10 Oct 2012 17:07:19 -0700 In-Reply-To: <92645B27BF79D04FBD2B0F8494FFD0F90FE41E@G2W2429.americas.hpqcorp.net> References: <92645B27BF79D04FBD2B0F8494FFD0F90FC806@G2W2429.americas.hpqcorp.net> <1349740633.11093.43.camel@sbsiddha-desk.sc.intel.com> <92645B27BF79D04FBD2B0F8494FFD0F90FE41E@G2W2429.americas.hpqcorp.net> Organization: Intel Corp Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.0.3 (3.0.3-1.fc15) Content-Transfer-Encoding: 7bit Message-ID: <1349914040.3042.12.camel@sbsiddha-desk.sc.intel.com> Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2012-10-10 at 00:26 +0000, Zhang, Lin-Bao (Linux Kernel R&D) wrote: > So , we can think ,as your patch , during the window , IO-apic is > useless or we can think IO-APIC doesn't exist ? > Could you mind please sharing your design details ? thanks very much! Between the window of interrupt-remapping enabled and the masked IO-APIC RTE's are configured properly, linux kernel doesn't wait/depend on any external interrupts. > > Can you please apply the appended patch to 2.6.32 kernel and see if the issue > > you mentioned gets fixed? If so, we can ask the -stable and OSV's teams to > > pick up this fix. > Yes , it can resolve current issue. Thanks for testing it out. I will add the appropriate changelog and send the patch out (to 2.6.32 stable and OSV kernels) with your "Tested-by:" if you are ok. thanks, suresh