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From:   Dionna Amalie Glaze <dionnaglaze@google.com>
Date:   Thu, 27 Apr 2023 18:29:07 -0700
Message-ID: <CAAH4kHbRmeK3SuEeryWnaU_daFcqPF==gU0H=fneJ2q9OmdG0g@mail.gmail.com>
Subject: Re: [PATCH v2 2/3] virt: tdx-guest: Add Quote generation support
To:     Sathyanarayanan Kuppuswamy 
        <sathyanarayanan.kuppuswamy@linux.intel.com>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>, x86@kernel.org,
        Shuah Khan <shuah@kernel.org>,
        Jonathan Corbet <corbet@lwn.net>,
        "H . Peter Anvin" <hpa@zytor.com>,
        "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
        Tony Luck <tony.luck@intel.com>,
        Wander Lairson Costa <wander@redhat.com>,
        Erdem Aktas <erdemaktas@google.com>,
        Chong Cai <chongc@google.com>, Qinkun Bao <qinkun@apache.org>,
        Guorui Yu <GuoRui.Yu@linux.alibaba.com>,
        Du Fan <fan.du@intel.com>, linux-kernel@vger.kernel.org,
        linux-kselftest@vger.kernel.org, linux-doc@vger.kernel.org
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>
> How about the following?
>
> Although this method reserves a fixed chunk of memory for GetQuote
> requests, such one-time allocation is preferable to the alternative
> choice of repeatedly allocating/freeing the shared buffer in the
> TDX_CMD_GET_QUOTE IOCTL handler, which will damage the direct map (because
> the sharing/unsharing process modifies the direct map). This allocation
> model is similar to that used by the AMD SEV guest driver.
>
>

Yes, this is clear, thank you.


-- 
-Dionna Glaze, PhD (she/her)