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Message-ID: <30c3da01-5284-6915-cc91-188577ed148d@oracle.com>
Date:   Tue, 15 Mar 2022 20:52:11 -0400
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Subject: Re: [PATCH 1/2] xen/grant-table: remove gnttab_*transfer*() functions
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To:     Juergen Gross <jgross@suse.com>, xen-devel@lists.xenproject.org,
        linux-kernel@vger.kernel.org
Cc:     Stefano Stabellini <sstabellini@kernel.org>
References: <20220311103429.12845-1-jgross@suse.com>
 <20220311103429.12845-2-jgross@suse.com>
 <63365484-7035-f2bd-5317-2e95d65993f7@oracle.com>
 <1633fb91-3771-e37c-14ce-43f1b0cda6a0@suse.com>
From:   Boris Ostrovsky <boris.ostrovsky@oracle.com>
In-Reply-To: <1633fb91-3771-e37c-14ce-43f1b0cda6a0@suse.com>
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On 3/15/22 2:10 AM, Juergen Gross wrote:
> On 15.03.22 00:37, Boris Ostrovsky wrote:
>>
>> On 3/11/22 5:34 AM, Juergen Gross wrote:
>>> All grant table operations related to the "transfer" functionality
>>> are unused currently. There have been users in the old days of the
>>> "Xen-o-Linux" kernel, but those didn't make it upstream.
>>>
>>> So remove the "transfer" related functions.
>>
>>
>> Do we need to assert somewhere that transfer flags are not set?
> 
> This would be an orthogonal change, right? My patch is just removing
> never called functions.
> 

I was thinking of having this done as part of code removal (maybe as a separate patch).


> In any case I believe checking those flags is the job of the hypervisor.
> If an operation is illegal due to a transfer flag being set, it needs to
> be rejected at hypervisor level.

True.

Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>