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Subject: Re: [PATCH v3 1/2] iommu - Enable debugfs exposure of the IOMMU
To:     "Mehta, Sohil" <sohil.mehta@intel.com>,
        "gary.hook@amd.com" <gary.hook@amd.com>,
        "iommu@lists.linux-foundation.org" <iommu@lists.linux-foundation.org>
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From:   "Hook, Gary" <ghook@amd.com>
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Date:   Tue, 17 Apr 2018 13:36:33 -0400
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On 4/13/2018 7:55 PM, Mehta, Sohil wrote:
> On Fri, 2018-04-06 at 08:17 -0500, Gary R Hook wrote:
>>   
>>   
>> +struct dentry *iommu_debugfs_setup(void)
>> +{
>> +	if (!debugfs_initialized())
> 
> This check is probably not needed.

Ah, so it isn't. Thank you.

> 
>> +		return NULL;
>> +
>> +	if (!iommu_debugfs_dir)
>> +		iommu_debugfs_dir = debugfs_create_dir("iommu",
>> NULL);
>> +
>> +	if (iommu_debugfs_dir)
>> +		pr_warn("WARNING: IOMMU DEBUGFS SUPPORT HAS BEEN
>> ENABLED IN THIS KERNEL\n");
>> +
> 
> As this gets called for each IOMMU, do you want to use pr_warn_once?

That works, yes.

> 
>> +	return iommu_debugfs_dir;
>> +}
>> +EXPORT_SYMBOL_GPL(iommu_debugfs_setup);
> 
> -Sohil
>