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Date: Tue, 15 Mar 2016 11:26:50 +0100 (CET)
From: Julia Lawall <julia.lawall@lip6.fr>
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To: alex.williamson@redhat.com, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org
cc: Alexander Gordeev <agordeev@redhat.com>,
        Bjorn Helgaas <bhelgaas@google.com>,
        Alex Williamson <alex.williamson@redhat.com>
Subject: question about pci_enable_msix_range
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Hello,

I was looking at the following code in the file
drivers/vfio/pci/vfio_pci_intrs.c:

                ret = pci_enable_msix_range(pdev, vdev->msix, 1, nvec);
                if (ret < nvec) {
                        if (ret > 0)
                                pci_disable_msix(pdev);
                        kfree(vdev->msix);
                        kfree(vdev->ctx);
                        return ret;
                }

I was wondering what is the point of using a range of 1 .. nvec if there
is going to be a failure if the number of allocated irqs is less than
nvec?

thanks,
julia