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Subject: Re: [PATCH v4 02/16] ACPI/IORT: Remove direct access of
 dev->iommu_fwspec
To:     Joerg Roedel <joro@8bytes.org>, <iommu@lists.linux-foundation.org>
CC:     <linux-kernel@vger.kernel.org>, <linux-arm-msm@vger.kernel.org>,
        <linux-mediatek@lists.infradead.org>,
        Sudeep Holla <sudeep.holla@arm.com>,
        Rob Clark <robdclark@gmail.com>, Sean Paul <sean@poorly.run>,
        Will Deacon <will@kernel.org>,
        Robin Murphy <robin.murphy@arm.com>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        Thierry Reding <thierry.reding@gmail.com>,
        Jean-Philippe Brucker <jean-philippe@linaro.org>,
        Andy Gross <agross@kernel.org>,
        Bjorn Andersson <bjorn.andersson@linaro.org>,
        "Greg Kroah-Hartman" <gregkh@linuxfoundation.org>,
        Joerg Roedel <jroedel@suse.de>
References: <20200326150841.10083-1-joro@8bytes.org>
 <20200326150841.10083-3-joro@8bytes.org>
From:   Hanjun Guo <guohanjun@huawei.com>
Message-ID: <82dea1be-4a2e-e914-c607-8aeb924eb36f@huawei.com>
Date:   Fri, 27 Mar 2020 11:30:53 +0800
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On 2020/3/26 23:08, Joerg Roedel wrote:
> From: Joerg Roedel <jroedel@suse.de>
> 
> Use the accessor functions instead of directly dereferencing
> dev->iommu_fwspec.
> 
> Tested-by: Hanjun Guo <guohanjun@huawei.com>
> Reviewed-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
> Signed-off-by: Joerg Roedel <jroedel@suse.de>
> ---
>  drivers/acpi/arm64/iort.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
> index ed3d2d1a7ae9..7d04424189df 100644
> --- a/drivers/acpi/arm64/iort.c
> +++ b/drivers/acpi/arm64/iort.c
> @@ -1015,6 +1015,7 @@ const struct iommu_ops *iort_iommu_configure(struct device *dev)
>  		return ops;
>  
>  	if (dev_is_pci(dev)) {
> +		struct iommu_fwspec *fwspec;
>  		struct pci_bus *bus = to_pci_dev(dev)->bus;
>  		struct iort_pci_alias_info info = { .dev = dev };
>  
> @@ -1027,8 +1028,9 @@ const struct iommu_ops *iort_iommu_configure(struct device *dev)
>  		err = pci_for_each_dma_alias(to_pci_dev(dev),
>  					     iort_pci_iommu_init, &info);

...

>  
> -		if (!err && iort_pci_rc_supports_ats(node))
> -			dev->iommu_fwspec->flags |= IOMMU_FWSPEC_PCI_RC_ATS;
> +		fwspec = dev_iommu_fwspec_get(dev);
> +		if (fwspec && iort_pci_rc_supports_ats(node))

Should we check !err as well?

Thanks
Hanjun

> +			fwspec->flags |= IOMMU_FWSPEC_PCI_RC_ATS;
>  	} else {
>  		int i = 0;
>  
>