Date:   Tue, 7 Dec 2021 15:08:03 -0600
From:   Bjorn Helgaas <helgaas@kernel.org>
To:     Thomas Gleixner <tglx@linutronix.de>
Cc:     LKML <linux-kernel@vger.kernel.org>, Marc Zygnier <maz@kernel.org>,
        Alex Williamson <alex.williamson@redhat.com>,
        Kevin Tian <kevin.tian@intel.com>,
        Jason Gunthorpe <jgg@nvidia.com>,
        Megha Dey <megha.dey@intel.com>,
        Ashok Raj <ashok.raj@intel.com>, linux-pci@vger.kernel.org,
        Cedric Le Goater <clg@kaod.org>,
        xen-devel@lists.xenproject.org, Juergen Gross <jgross@suse.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Niklas Schnelle <schnelle@linux.ibm.com>,
        linux-s390@vger.kernel.org, Heiko Carstens <hca@linux.ibm.com>,
        Christian Borntraeger <borntraeger@de.ibm.com>,
        Logan Gunthorpe <logang@deltatee.com>,
        Jon Mason <jdmason@kudzu.us>,
        Dave Jiang <dave.jiang@intel.com>,
        Allen Hubbe <allenbh@gmail.com>, linux-ntb@googlegroups.com
Subject: Re: [patch V2 19/31] PCI: hv: Rework MSI handling
Message-ID: <20211207210803.GA78366@bhelgaas>
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In-Reply-To: <20211206210748.629363944@linutronix.de>
Precedence: bulk

On Mon, Dec 06, 2021 at 11:51:33PM +0100, Thomas Gleixner wrote:
> Replace the about to vanish iterators and make use of the filtering. Take
> the descriptor lock around the iterators.
> 
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Acked-by: Bjorn Helgaas <bhelgaas@google.com>

> ---
>  drivers/pci/controller/pci-hyperv.c |   15 ++++++++++-----
>  1 file changed, 10 insertions(+), 5 deletions(-)
> 
> --- a/drivers/pci/controller/pci-hyperv.c
> +++ b/drivers/pci/controller/pci-hyperv.c
> @@ -3445,18 +3445,23 @@ static int hv_pci_suspend(struct hv_devi
>  
>  static int hv_pci_restore_msi_msg(struct pci_dev *pdev, void *arg)
>  {
> -	struct msi_desc *entry;
>  	struct irq_data *irq_data;
> +	struct msi_desc *entry;
> +	int ret = 0;
>  
> -	for_each_pci_msi_entry(entry, pdev) {
> +	msi_lock_descs(&pdev->dev);
> +	msi_for_each_desc(entry, &pdev->dev, MSI_DESC_ASSOCIATED) {
>  		irq_data = irq_get_irq_data(entry->irq);
> -		if (WARN_ON_ONCE(!irq_data))
> -			return -EINVAL;
> +		if (WARN_ON_ONCE(!irq_data)) {
> +			ret = -EINVAL;
> +			break;
> +		}
>  
>  		hv_compose_msi_msg(irq_data, &entry->msg);
>  	}
> +	msi_unlock_descs(&pdev->dev);
>  
> -	return 0;
> +	return ret;
>  }
>  
>  /*
>