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Date:   Thu, 3 Nov 2022 23:25:19 +0800
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Subject: Re: [PATCH 10/12] Drivers: hv: Don't remap addresses that are above
 shared_gpa_boundary
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To:     Michael Kelley <mikelley@microsoft.com>, hpa@zytor.com,
        kys@microsoft.com, haiyangz@microsoft.com, sthemmin@microsoft.com,
        wei.liu@kernel.org, decui@microsoft.com, luto@kernel.org,
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        mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com,
        Tianyu.Lan@microsoft.com, kirill.shutemov@linux.intel.com,
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References: <1666288635-72591-1-git-send-email-mikelley@microsoft.com>
 <1666288635-72591-11-git-send-email-mikelley@microsoft.com>
From:   Tianyu Lan <ltykernel@gmail.com>
In-Reply-To: <1666288635-72591-11-git-send-email-mikelley@microsoft.com>
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On 10/21/2022 1:57 AM, Michael Kelley wrote:
> With the vTOM bit now treated as a protection flag and not part of
> the physical address, avoid remapping physical addresses with vTOM set
> since technically such addresses aren't valid.  Use ioremap_cache()
> instead of memremap() to ensure that the mapping provides decrypted
> access, which will correctly set the vTOM bit as a protection flag.
> 
> While this change is not required for correctness with the current
> implementation of memremap(), for general code hygiene it's better to
> not depend on the mapping functions doing something reasonable with
> a physical address that is out-of-range.
> 
> While here, fix typos in two error messages.
> 
> Signed-off-by: Michael Kelley<mikelley@microsoft.com>
> ---

Reviewed-by: Tianyu Lan <Tianyu.Lan@microsoft.com>