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Date:   Mon, 23 Oct 2023 10:59:35 -0300
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Nicolin Chen <nicolinc@nvidia.com>
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Subject: Re: [PATCH v4 08/17] iommufd: Always setup MSI and anforce cc on
 kernel-managed domains
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On Sun, Oct 22, 2023 at 05:18:03PM -0700, Nicolin Chen wrote:

> > > And where should we add this comment? Kdoc of
> > > the alloc uAPI?
> > 
> > Maybe right in front of the only enforce_cc op callback?
> 
> OK. How about this? Might be a bit verbose though:
> 	/*
> 	 * enforce_cache_coherenc must be determined during the HWPT allocation.
> 	 * Note that a HWPT (non-CC) created for a device (non-CC) can be later
> 	 * reused by another device (either non-CC or CC). However, A HWPT (CC)
> 	 * created for a device (CC) cannot be reused by another device (non-CC)
> 	 * but only devices (CC). Instead user space in this case would need to
> 	 * allocate a separate HWPT (non-CC).
> 	 */

Ok, fix the spello in enforce_cache_coherenc

Jason