Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935102AbcKWXVF (ORCPT ); Wed, 23 Nov 2016 18:21:05 -0500 Received: from mail.kernel.org ([198.145.29.136]:35092 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752998AbcKWXVC (ORCPT ); Wed, 23 Nov 2016 18:21:02 -0500 Date: Wed, 23 Nov 2016 17:20:27 -0600 From: Bjorn Helgaas To: Long Li Cc: "K. Y. Srinivasan" , Haiyang Zhang , Bjorn Helgaas , devel@linuxdriverproject.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, Long Li Subject: Re: [PATCH] pci-hyperv: use kmalloc to allocate hypercall params buffer Message-ID: <20161123232027.GM16033@bhelgaas-glaptop.roam.corp.google.com> References: <1478642678-31659-1-git-send-email-longli@exchange.microsoft.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1478642678-31659-1-git-send-email-longli@exchange.microsoft.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3864 Lines: 104 On Tue, Nov 08, 2016 at 02:04:38PM -0800, Long Li wrote: > From: Long Li > > hv_do_hypercall assumes that we pass a segment from a physically > continuous buffer. Buffer allocated on the stack may not work if > CONFIG_VMAP_STACK=y is set. > > Change to use kmalloc to allocate this buffer. > > The v2 patch adds locking to access the pre-allocated buffer. > > Signed-off-by: Long Li > Reported-by: Haiyang Zhang Waiting for a maintainer ack for this. $ ./scripts/get_maintainer.pl -f drivers/pci/host/pci-hyperv.c "K. Y. Srinivasan" (maintainer:Hyper-V CORE AND DRIVERS) Haiyang Zhang (maintainer:Hyper-V CORE AND DRIVERS) ... > --- > drivers/pci/host/pci-hyperv.c | 29 +++++++++++++++++++---------- > 1 file changed, 19 insertions(+), 10 deletions(-) > > diff --git a/drivers/pci/host/pci-hyperv.c b/drivers/pci/host/pci-hyperv.c > index 763ff87..ca553df 100644 > --- a/drivers/pci/host/pci-hyperv.c > +++ b/drivers/pci/host/pci-hyperv.c > @@ -378,6 +378,8 @@ struct hv_pcibus_device { > struct msi_domain_info msi_info; > struct msi_controller msi_chip; > struct irq_domain *irq_domain; > + struct retarget_msi_interrupt retarget_msi_interrupt_params; > + spinlock_t retarget_msi_interrupt_lock;; > }; > > /* > @@ -774,34 +776,40 @@ void hv_irq_unmask(struct irq_data *data) > { > struct msi_desc *msi_desc = irq_data_get_msi_desc(data); > struct irq_cfg *cfg = irqd_cfg(data); > - struct retarget_msi_interrupt params; > + struct retarget_msi_interrupt *params; > struct hv_pcibus_device *hbus; > struct cpumask *dest; > struct pci_bus *pbus; > struct pci_dev *pdev; > int cpu; > + unsigned long flags; > > dest = irq_data_get_affinity_mask(data); > pdev = msi_desc_to_pci_dev(msi_desc); > pbus = pdev->bus; > hbus = container_of(pbus->sysdata, struct hv_pcibus_device, sysdata); > > - memset(¶ms, 0, sizeof(params)); > - params.partition_id = HV_PARTITION_ID_SELF; > - params.source = 1; /* MSI(-X) */ > - params.address = msi_desc->msg.address_lo; > - params.data = msi_desc->msg.data; > - params.device_id = (hbus->hdev->dev_instance.b[5] << 24) | > + spin_lock_irqsave(&hbus->retarget_msi_interrupt_lock, flags); > + > + params = &hbus->retarget_msi_interrupt_params; > + memset(params, 0, sizeof(*params)); > + params->partition_id = HV_PARTITION_ID_SELF; > + params->source = 1; /* MSI(-X) */ > + params->address = msi_desc->msg.address_lo; > + params->data = msi_desc->msg.data; > + params->device_id = (hbus->hdev->dev_instance.b[5] << 24) | > (hbus->hdev->dev_instance.b[4] << 16) | > (hbus->hdev->dev_instance.b[7] << 8) | > (hbus->hdev->dev_instance.b[6] & 0xf8) | > PCI_FUNC(pdev->devfn); > - params.vector = cfg->vector; > + params->vector = cfg->vector; > > for_each_cpu_and(cpu, dest, cpu_online_mask) > - params.vp_mask |= (1ULL << vmbus_cpu_number_to_vp_number(cpu)); > + params->vp_mask |= (1ULL << vmbus_cpu_number_to_vp_number(cpu)); > + > + hv_do_hypercall(HVCALL_RETARGET_INTERRUPT, params, NULL); > > - hv_do_hypercall(HVCALL_RETARGET_INTERRUPT, ¶ms, NULL); > + spin_unlock_irqrestore(&hbus->retarget_msi_interrupt_lock, flags); > > pci_msi_unmask_irq(data); > } > @@ -2186,6 +2194,7 @@ static int hv_pci_probe(struct hv_device *hdev, > INIT_LIST_HEAD(&hbus->resources_for_children); > spin_lock_init(&hbus->config_lock); > spin_lock_init(&hbus->device_list_lock); > + spin_lock_init(&hbus->retarget_msi_interrupt_lock); > sema_init(&hbus->enum_sem, 1); > init_completion(&hbus->remove_event); > > -- > 2.7.4 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-pci" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html