From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Grall Subject: [PATCH v4 12/18] xen/arm: IRQ: Do not allow IRQ to be shared between domains and XEN Date: Tue, 22 Apr 2014 13:58:44 +0100 Message-ID: <1398171530-27391-13-git-send-email-julien.grall@linaro.org> References: <1398171530-27391-1-git-send-email-julien.grall@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1WcaIb-0001i9-BN for xen-devel@lists.xenproject.org; Tue, 22 Apr 2014 12:59:45 +0000 Received: by mail-ee0-f41.google.com with SMTP id t10so4662116eei.14 for ; Tue, 22 Apr 2014 05:59:13 -0700 (PDT) In-Reply-To: <1398171530-27391-1-git-send-email-julien.grall@linaro.org> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: xen-devel@lists.xenproject.org Cc: stefano.stabellini@citrix.com, Julien Grall , tim@xen.org, ian.campbell@citrix.com List-Id: xen-devel@lists.xenproject.org The current dt_route_irq_to_guest implementation sets IRQ_GUEST even if the IRQ is correctly setup. An IRQ can be shared between devices, if the devices are not assigned to the same domain or Xen, then this could result in routing the IRQ to the domain instead of Xen ... Also avoid to relying on wrong the behaviour when Xen is routing an IRQ to DOM0. Therefore check the return code from route_dt_irq_to_guest in map_device. Signed-off-by: Julien Grall Acked-by: Ian Campbell --- Changes in v4: - Don't forget to free action if sanity check has failed Changes in v3: - Fix typoes and update commit message Changes in v2: - Use EBUSY instead of EADDRINUSE for error code - Don't hardcode the domain in error message - Fix typo in error message - Use irq_get_domain --- xen/arch/arm/domain_build.c | 9 +++++++-- xen/arch/arm/irq.c | 41 +++++++++++++++++++++++++++++++++++++---- 2 files changed, 44 insertions(+), 6 deletions(-) diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c index 5b636c8..9dcff1c 100644 --- a/xen/arch/arm/domain_build.c +++ b/xen/arch/arm/domain_build.c @@ -725,8 +725,13 @@ static int map_device(struct domain *d, const struct dt_device_node *dev) } DPRINT("irq %u = %u type = 0x%x\n", i, irq.irq, irq.type); - /* Don't check return because the IRQ can be use by multiple device */ - route_dt_irq_to_guest(d, &irq, dt_node_name(dev)); + res = route_dt_irq_to_guest(d, &irq, dt_node_name(dev)); + if ( res ) + { + printk(XENLOG_ERR "Unable to route IRQ %u to domain %u\n", + irq.irq, d->domain_id); + return res; + } } /* Map the address ranges */ diff --git a/xen/arch/arm/irq.c b/xen/arch/arm/irq.c index 9f1ca40..44696e7 100644 --- a/xen/arch/arm/irq.c +++ b/xen/arch/arm/irq.c @@ -256,6 +256,16 @@ int setup_dt_irq(const struct dt_irq *irq, struct irqaction *new) spin_lock_irqsave(&desc->lock, flags); + if ( desc->status & IRQ_GUEST ) + { + struct domain *d = irq_get_domain(desc); + + spin_unlock_irqrestore(&desc->lock, flags); + printk(XENLOG_ERR "ERROR: IRQ %u is already in use by the domain %u\n", + irq->irq, d->domain_id); + return -EBUSY; + } + disabled = (desc->action == NULL); rc = __setup_irq(desc, new); @@ -292,7 +302,7 @@ int route_dt_irq_to_guest(struct domain *d, const struct dt_irq *irq, struct irqaction *action; struct irq_desc *desc = irq_to_desc(irq->irq); unsigned long flags; - int retval; + int retval = 0; bool_t level; action = xmalloc(struct irqaction); @@ -305,19 +315,42 @@ int route_dt_irq_to_guest(struct domain *d, const struct dt_irq *irq, spin_lock_irqsave(&desc->lock, flags); - retval = __setup_irq(desc, action); - if ( retval ) + /* If the IRQ is already used by someone + * - If it's the same domain -> Xen doesn't need to update the IRQ desc + * - Otherwise -> For now, don't allow the IRQ to be shared between + * Xen and domains. + */ + if ( desc->action != NULL ) { - xfree(action); + struct domain *ad = irq_get_domain(desc); + + if ( (desc->status & IRQ_GUEST) && d == ad ) + goto out; + + if ( desc->status & IRQ_GUEST ) + printk(XENLOG_ERR "ERROR: IRQ %u is already used by domain %u\n", + irq->irq, ad->domain_id); + else + printk(XENLOG_ERR "ERROR: IRQ %u is already used by Xen\n", + irq->irq); + retval = -EBUSY; goto out; } + retval = __setup_irq(desc, action); + if ( retval ) + goto out; + level = dt_irq_is_level_triggered(irq); gic_route_irq_to_guest(d, desc, level, cpumask_of(smp_processor_id()), GIC_PRI_IRQ); + spin_unlock_irqrestore(&desc->lock, flags); + return 0; out: spin_unlock_irqrestore(&desc->lock, flags); + xfree(action); + return retval; } -- 1.7.10.4