From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754737Ab2EUPyo (ORCPT ); Mon, 21 May 2012 11:54:44 -0400 Received: from smtp02.citrix.com ([66.165.176.63]:60650 "EHLO SMTP02.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750817Ab2EUPyn (ORCPT ); Mon, 21 May 2012 11:54:43 -0400 X-IronPort-AV: E=Sophos;i="4.75,631,1330923600"; d="scan'208";a="195812786" From: Stefano Stabellini To: xen-devel@lists.xensource.com CC: stefano.stabellini@eu.citrix.com, konrad.wilk@oracle.com, linux-kernel@vger.kernel.org Subject: [PATCH] xen: do not map the same GSI twice Date: Mon, 21 May 2012 16:54:10 +0100 Message-ID: <1337615650-27911-1-git-send-email-stefano.stabellini@eu.citrix.com> X-Mailer: git-send-email 1.7.0.4 MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org PV on HVM guests map GSIs into event channels; at restore time the event channels are resumed by restore_pirqs. Device drivers might try to register the same GSI again through ACPI at restore time, but the GSI has already been mapped and bound by restore_pirqs. This patch detects these situations and avoid mapping the same GSI multiple times. Signed-off-by: Stefano Stabellini --- arch/x86/pci/xen.c | 4 ++++ drivers/xen/events.c | 5 +++-- include/xen/events.h | 3 +++ 3 files changed, 10 insertions(+), 2 deletions(-) diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c index 7415aa9..56ab749 100644 --- a/arch/x86/pci/xen.c +++ b/arch/x86/pci/xen.c @@ -64,6 +64,10 @@ static int xen_register_pirq(u32 gsi, int gsi_override, int triggering, int shareable = 0; char *name; + irq = xen_irq_from_gsi(gsi); + if (irq > 0) + return irq; + if (set_pirq) pirq = gsi; diff --git a/drivers/xen/events.c b/drivers/xen/events.c index 0a8a17c..6908e4c 100644 --- a/drivers/xen/events.c +++ b/drivers/xen/events.c @@ -611,7 +611,7 @@ static void disable_pirq(struct irq_data *data) disable_dynirq(data); } -static int find_irq_by_gsi(unsigned gsi) +int xen_irq_from_gsi(unsigned gsi) { struct irq_info *info; @@ -625,6 +625,7 @@ static int find_irq_by_gsi(unsigned gsi) return -1; } +EXPORT_SYMBOL_GPL(xen_irq_from_gsi); /* * Do not make any assumptions regarding the relationship between the @@ -644,7 +645,7 @@ int xen_bind_pirq_gsi_to_irq(unsigned gsi, mutex_lock(&irq_mapping_update_lock); - irq = find_irq_by_gsi(gsi); + irq = xen_irq_from_gsi(gsi); if (irq != -1) { printk(KERN_INFO "xen_map_pirq_gsi: returning irq %d for gsi %u\n", irq, gsi); diff --git a/include/xen/events.h b/include/xen/events.h index 0f77370..b332bd7 100644 --- a/include/xen/events.h +++ b/include/xen/events.h @@ -103,6 +103,9 @@ int xen_irq_from_pirq(unsigned pirq); /* Return the pirq allocated to the irq. */ int xen_pirq_from_irq(unsigned irq); +/* Return the irq allocated to the gsi */ +int xen_irq_from_gsi (unsigned gsi); + /* Determine whether to ignore this IRQ if it is passed to a guest. */ int xen_test_irq_shared(int irq); -- 1.7.2.5