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Date:   Mon, 2 Oct 2023 08:11:43 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Chris Leech <cleech@redhat.com>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Christoph Hellwig <hch@lst.de>,
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Subject: Re: [PATCH 2/3] cnic,bnx2,bnx2x: page align uio mmap allocations
Message-ID: <20231002061143.GB911@lst.de>
References: <20230929170023.1020032-1-cleech@redhat.com> <20230929170023.1020032-3-cleech@redhat.com>
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On Fri, Sep 29, 2023 at 10:00:22AM -0700, Chris Leech wrote:
> Allocations in these drivers that will be mmaped through a uio device
> should be made in multiples of PAGE_SIZE to avoid exposing additional
> kernel memory unintentionally.

dma coherent allocations are always rounded up to a page, although
the documentation for that is somewhat obscure and I wouldn't fault
anyone for not relying on it.