From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754861AbZCXVS1 (ORCPT ); Tue, 24 Mar 2009 17:18:27 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754360AbZCXVQR (ORCPT ); Tue, 24 Mar 2009 17:16:17 -0400 Received: from hera.kernel.org ([140.211.167.34]:60235 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754196AbZCXVQP (ORCPT ); Tue, 24 Mar 2009 17:16:15 -0400 Date: Tue, 24 Mar 2009 21:15:31 GMT From: Yinghai Lu To: linux-tip-commits@vger.kernel.org Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@redhat.com, yinghai@kernel.org, rusty@rustcorp.com.au, ebiederm@xmission.com, tglx@linutronix.de, mingo@elte.hu Reply-To: mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, yinghai@kernel.org, rusty@rustcorp.com.au, ebiederm@xmission.com, tglx@linutronix.de, mingo@elte.hu In-Reply-To: <49C94134.4000408@kernel.org> References: <49C94134.4000408@kernel.org> Subject: [tip:x86/apic] x86: fix set_extra_move_desc calling Message-ID: Git-Commit-ID: fa74c9073370e57fa28e02aff13f4d7b1806505c X-Mailer: tip-git-log-daemon MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.0 (hera.kernel.org [127.0.0.1]); Tue, 24 Mar 2009 21:15:34 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: fa74c9073370e57fa28e02aff13f4d7b1806505c Gitweb: http://git.kernel.org/tip/fa74c9073370e57fa28e02aff13f4d7b1806505c Author: Yinghai Lu AuthorDate: Tue, 24 Mar 2009 13:23:16 -0700 Committer: Ingo Molnar CommitDate: Tue, 24 Mar 2009 22:12:10 +0100 x86: fix set_extra_move_desc calling Impact: fix bug with irq-descriptor moving when logical flat Rusty observed: > The effect of setting desc->affinity (ie. from userspace via sysfs) has varied > over time. In 2.6.27, the 32-bit code anded the value with cpu_online_map, > and both 32 and 64-bit did that anding whenever a cpu was unplugged. > > 2.6.29 consolidated this into one routine (and fixed hotplug) but introduced > another variation: anding the affinity with cfg->domain. Is this right, or > should we just set it to what the user said? Or as now, indicate that we're > restricting it. Eric pointed out that desc->affinity should be what the user requested, if it is at all possible to honor the user space request. This bug got introduced by commit 22f65d31b "x86: Update io_apic.c to use new cpumask API". Fix it by moving the masking to before the descriptor moving ... Reported-by: Rusty Russell Reported-by: Eric W. Biederman LKML-Reference: <49C94134.4000408@kernel.org> Signed-off-by: Ingo Molnar --- arch/x86/kernel/apic/io_apic.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c index 86827d8..1ed6c06 100644 --- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -592,8 +592,9 @@ set_desc_affinity(struct irq_desc *desc, const struct cpumask *mask) if (assign_irq_vector(irq, cfg, mask)) return BAD_APICID; - cpumask_and(desc->affinity, cfg->domain, mask); + /* check that before desc->addinity get updated */ set_extra_move_desc(desc, mask); + cpumask_and(desc->affinity, cfg->domain, mask); return apic->cpu_mask_to_apicid_and(desc->affinity, cpu_online_mask); }