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Subject: Re: [PATCH v8 3/7] swiotlb: Zero out bounce buffer for untrusted
 device
To:     Christoph Hellwig <hch@lst.de>
References: <20190830071718.16613-1-baolu.lu@linux.intel.com>
 <20190830071718.16613-4-baolu.lu@linux.intel.com>
 <20190830073130.GA10471@lst.de>
From:   Lu Baolu <baolu.lu@linux.intel.com>
Message-ID: <a5edd268-5ba7-a8b6-d883-f4761e52fdff@linux.intel.com>
Date:   Mon, 2 Sep 2019 09:58:27 +0800
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Hi Christoph,

On 8/30/19 3:31 PM, Christoph Hellwig wrote:
> On Fri, Aug 30, 2019 at 03:17:14PM +0800, Lu Baolu wrote:
>> +#include <linux/pci.h>
> 
>> +	if (dev_is_untrusted(hwdev) && zero_size)
>> +		memset(zero_addr, 0, zero_size);
> 
> As said before swiotlb must not grow pci dependencies like this.

I understand your concern. I will try to remove this dependency in the
next version.

> Please move the untrusted flag to struct device.

The untrusted flag is introduced in another series. I agree that we
could consider to move it to struct device, but I think making it
in a separated patch looks better.

Best regards,
Lu Baolu