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Date:   Mon, 12 Jul 2021 14:56:45 +0100
From:   Will Deacon <will@kernel.org>
To:     Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc:     Christoph Hellwig <hch@lst.de>,
        Robin Murphy <robin.murphy@arm.com>,
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Subject: Re: [PATCH v15 06/12] swiotlb: Use is_swiotlb_force_bounce for
 swiotlb data bouncing
Message-ID: <20210712135645.GA28881@willie-the-truck>
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On Tue, Jul 06, 2021 at 12:59:57PM -0400, Konrad Rzeszutek Wilk wrote:
> On Tue, Jul 06, 2021 at 05:57:21PM +0100, Will Deacon wrote:
> > On Tue, Jul 06, 2021 at 10:46:07AM -0400, Konrad Rzeszutek Wilk wrote:
> > > On Tue, Jul 06, 2021 at 04:05:13PM +0200, Christoph Hellwig wrote:
> > > > On Tue, Jul 06, 2021 at 03:01:04PM +0100, Robin Murphy wrote:
> > > > > FWIW I was pondering the question of whether to do something along those 
> > > > > lines or just scrap the default assignment entirely, so since I hadn't got 
> > > > > round to saying that I've gone ahead and hacked up the alternative 
> > > > > (similarly untested) for comparison :)
> > > > >
> > > > > TBH I'm still not sure which one I prefer...
> > > > 
> > > > Claire did implement something like your suggestion originally, but
> > > > I don't really like it as it doesn't scale for adding multiple global
> > > > pools, e.g. for the 64-bit addressable one for the various encrypted
> > > > secure guest schemes.
> > > 
> > > Couple of things:
> > >  - I am not pushing to Linus the Claire's patchset until we have a
> > >    resolution on this. I hope you all agree that is a sensible way
> > >    forward as much as I hate doing that.
> > 
> > Sure, it's a pity but we could clearly use a bit more time to get these
> > just right and we've run out of time for 5.14.
> > 
> > I think the main question I have is how would you like to see patches for
> > 5.15? i.e. as patches on top of devel/for-linus-5.14 or something else?
> 
> Yes that would be perfect. If there are any dependencies on the rc1, I
> can rebase it on top of that.

Yes, please, rebasing would be very helpful. The broader rework of
'io_tlb_default_mem' is going to conflict quite badly otherwise.

Cheers,

Will