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Date:   Tue, 6 Sep 2022 12:59:31 +0100
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Subject: Re: [PATCH 0/3] iova: Some misc changes
To:     Robin Murphy <robin.murphy@arm.com>, <joro@8bytes.org>,
        <will@kernel.org>
CC:     <iommu@lists.linux.dev>, <linux-kernel@vger.kernel.org>
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From:   John Garry <john.garry@huawei.com>
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On 05/09/2022 16:51, Robin Murphy wrote:
>>
>> Any thoughts on this? Since I got no review of patch #3 I assume that 
>> it is not keenly welcome either.
> 
> Yeah, I applied patch #3 to have a look at the result, but couldn't 
> really convince myself either way - there are certainly a few functions 
> in weirdly incongruous places at the moment, but afterwards we end up 
> with certain other things in rather contrived order for the sake of 
> avoiding declarations, so overall it just didn't feel objectively better 
> to me. Plus the fact that rewriting nearly 2/3 of the file stands to 
> make backporting tweaks or fixes unnecessarily painful is hard to 
> overlook. 

Yeah, that was my main concern. But if it is going to be done, then now 
is as good a time as ever...

> Hence I guess I'm leaning towards "worth trying to see how it 
> looked, but let's not".
> 

ok, fine. But I do still feel that iova.c does need tidying to some 
extent along these lines.

> As for the stubs, it seems that they're currently unused due to linkage 
> issues with IOMMU_IOVA=m - if we want better compile-test coverage, I 
> wonder if we couldn't replace the IS_ENABLED() with IS_REACHABLE() and 
> restore some of the previously-conditional selects?

Sorry, but I am not familiar - what were some examples of 
previously-conditional selects?

Thanks,
John