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Date:   Mon, 21 Jun 2021 22:19:46 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Stefano Stabellini <sstabellini@kernel.org>
Cc:     Christoph Hellwig <hch@lst.de>,
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Subject: Re: [PATCH v13 01/12] swiotlb: Refactor swiotlb init functions
Message-ID: <20210621201946.GA13822@lst.de>
References: <20210617062635.1660944-1-tientzu@chromium.org> <20210617062635.1660944-2-tientzu@chromium.org> <alpine.DEB.2.21.2106171434480.24906@sstabellini-ThinkPad-T480s> <CALiNf29SJ0jXirWVDhJw4BUNvkjUeGPyGNJK9m8c30OPX41=5Q@mail.gmail.com> <741a34cc-547c-984d-8af4-2f309880acfa@amd.com> <20210618143212.GA19284@lst.de> <alpine.DEB.2.21.2106211052270.24906@sstabellini-ThinkPad-T480s>
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On Mon, Jun 21, 2021 at 10:59:20AM -0700, Stefano Stabellini wrote:
> Just as a clarification: I was referring to the zeroing of "mem" in
> swiotlb_late_init_with_tbl and swiotlb_init_with_tbl. While it looks
> like Tom and Christoph are talking about the zeroing of "tlb".

Indeed. 

> 
> The zeroing of "mem" is required as some fields of struct io_tlb_mem
> need to be initialized to zero. While the zeroing of "tlb" is not
> required except from the point of view of not leaking sensitive data as
> Christoph mentioned.
> 
> Either way, Claire's v14 patch 01/12 looks fine to me.

Agreed.