From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@redhat.com>
Subject: Re: [PATCH 2/2] pci-assign: Fix MSI-X registration
Date: Mon, 10 Oct 2011 15:55:51 +0200
Message-ID: <4E92F967.3070601@redhat.com>
References: <20110922030909.4121.66872.stgit@s20.home> <20110922031242.4121.35090.stgit@s20.home> <4E7AFA02.5010409@siemens.com>
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Cc: Alex Williamson <alex.williamson@redhat.com>,
	"kvm@vger.kernel.org" <kvm@vger.kernel.org>,
	"yongjie.ren@intel.com" <yongjie.ren@intel.com>
To: Jan Kiszka <jan.kiszka@siemens.com>
Return-path: <kvm-owner@vger.kernel.org>
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On 09/22/2011 12:04 PM, Jan Kiszka wrote:
> >           goto out;
> >
> >  +    if (!kvm_check_extension(kvm_state, KVM_CAP_ASSIGN_DEV_IRQ)&&
> >  +        (dev->cap.available&  ASSIGNED_DEVICE_CAP_MSIX ||
> >  +         dev->cap.available&  ASSIGNED_DEVICE_CAP_MSI ||
> >  +         assigned_dev_pci_read_byte(pci_dev, PCI_INTERRUPT_PIN) != 0)) {
> >  +        goto out;
> >  +    }
> >  +
>
> That's not equivalent as it needlessly prevents IRQ support in the
> absence of KVM_CAP_ASSIGN_DEV_IRQ.
>
> Let's just fix the core issue and replace the test for
> KVM_CAP_DEVICE_MSIX with a test call of KVM_ASSIGN_SET_MSIX_NR, passing
> in a NULL struct. If it returns -EFAULT, the IOCTL is known and MSIX is
> supported.
>

Or just add KVM_CAP_DEVICE_MSIX to the kernel and backport it where needed?

-- 
error compiling committee.c: too many arguments to function