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Date:   Wed, 28 Apr 2021 12:18:19 -0400
From:   Sasha Levin <sashal@kernel.org>
To:     Jianxiong Gao <jxgao@google.com>
Cc:     Greg KH <greg@kroah.com>, stable@vger.kernel.org,
        marcorr@google.com
Subject: Re: [PATCH v5.10 0/8] preserve DMA offsets when using swiotlb
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On Mon, Apr 26, 2021 at 11:00:56AM -0700, Jianxiong Gao wrote:
>On Sat, Apr 24, 2021 at 7:43 AM Greg KH <greg@kroah.com> wrote:
>> Ok, and what prevents you from adding this new feature do your "custom"
>> kernel, or to use 5.12 instead?
>>
>> This is a new feature that Linux has never supported, and these patches
>> are not "trivial" at all.  I also do not see the maintainer of the
>> subsystem agreeing that these are needed to be backported, which is not
>> a good sign.
>>
>So this is not about a new feature. This is about an existing bug that
>we stumbled onto while using SEV virtualization. However SEV is not
>needed to trigger the bug. We have reproduced the bug with just
>NVMe + SWIOTLB=force option in Rhel 8 environment. Please note
>that NVMe and SWIOTLB=force are both existing feature and without
>the patch they don't work together. This is why we are proposing to merge
>the patches into the LTS kernels.

Could you re-spin this series with the comments around patch formatting
addressed, and explicitly cc hch on this to get his ack?

-- 
Thanks,
Sasha