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Date:   Thu, 11 Jun 2020 10:49:53 -0400
From:   "Alex Xu (Hello71)" <alex_y_xu@yahoo.ca>
Subject: Re: [patch for-5.8] dma-pool: decouple DMA_REMAP from
 DMA_COHERENT_POOL
To:     Christoph Hellwig <hch@lst.de>,
        David Rientjes <rientjes@google.com>
Cc:     alsa-devel@alsa-project.org, bp@alien8.de, hch@infradead.org,
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        Pavel Machek <pavel@ucw.cz>, perex@perex.cz,
        tglx@linutronix.de, tiwai@suse.com, x86@kernel.org
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Excerpts from David Rientjes's message of June 11, 2020 3:25 am:
> DMA_REMAP is an unnecessary requirement for AMD SEV, which requires=20
> DMA_COHERENT_POOL, so avoid selecting it when it is otherwise unnecessary=
. =20
>=20
> The only other requirement for DMA coherent pools is DMA_DIRECT_REMAP, so=
=20
> ensure that properly selects the config option when needed.
>=20
> Fixes: 82fef0ad811f ("x86/mm: unencrypted non-blocking DMA allocations us=
e=20
> coherent pools")
> Suggested-by: Christoph Hellwig <hch@lst.de>
> Signed-off-by: David Rientjes <rientjes@google.com>
> ---
>  kernel/dma/Kconfig | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
>=20

Works for me with SME on or off with af7b480103, and with SME off in=20
abfbb29297. There is some regression with amdgpu and SME between those=20
two points, I need to check that out too. I haven't tested either before=20
or after with SEV (which I'm not even sure my system supports).=20
Regardless, this is a definite improvement.

Tested-by: Alex Xu (Hello71) <alex_y_xu@yahoo.ca>

Thanks,
Alex.