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Date: Wed, 9 Apr 2025 12:53:32 +0200
From: Christoph Hellwig <hch@lst.de>
To: Roman Kisel <romank@linux.microsoft.com>
Cc: aleksander.lobakin@intel.com, andriy.shevchenko@linux.intel.com,
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Subject: Re: [PATCH hyperv-next 6/6] drivers: SCSI: Do not bounce-bufffer
 for the confidential VMBus
Message-ID: <20250409105332.GB5721@lst.de>
References: <20250409000835.285105-1-romank@linux.microsoft.com> <20250409000835.285105-7-romank@linux.microsoft.com>
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In-Reply-To: <20250409000835.285105-7-romank@linux.microsoft.com>
User-Agent: Mutt/1.5.17 (2007-11-01)

On Tue, Apr 08, 2025 at 05:08:35PM -0700, Roman Kisel wrote:
> The device bit that indicates that the device is capable of I/O
> with private pages lets avoid excessive copying in the Hyper-V
> SCSI driver.
> 
> Set that bit equal to the confidential external memory one to
> not bounce buffer

Drivers have absolutely no business telling this.  The need for bounce
buffering or not is a platform/IOMMU decision and not one specific to
a certain device or driver.