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Date:   Tue, 14 Sep 2021 18:51:01 -0700 (PDT)
From:   Stefano Stabellini <sstabellini@kernel.org>
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Subject: Re: [PATCH] swiotlb: set IO TLB segment size via cmdline
In-Reply-To: <20210914153046.GB815@lst.de>
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References: <20210914151016.3174924-1-Roman_Skakun@epam.com> <7c04db79-7de1-93ff-0908-9bad60a287b9@suse.com> <20210914153046.GB815@lst.de>
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On Tue, 14 Sep 2021, Christoph Hellwig wrote:
> On Tue, Sep 14, 2021 at 05:29:07PM +0200, Jan Beulich wrote:
> > I'm not convinced the swiotlb use describe there falls under "intended
> > use" - mapping a 1280x720 framebuffer in a single chunk? (As an aside,
> > the bottom of this page is also confusing, as following "Then we can
> > confirm the modified swiotlb size in the boot log:" there is a log
> > fragment showing the same original size of 64Mb.
> 
> It doesn't.  We also do not add hacks to the kernel for whacky out
> of tree modules.

Also, Option 1 listed in the webpage seems to be a lot better. Any
reason you can't do that? Because that option both solves the problem
and increases performance.