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Subject: Re: [RFC][PATCH 03/10] x86/mm: introduce "default" kernel PTE mask
To:     Tom Lendacky <thomas.lendacky@amd.com>,
        Nadav Amit <namit@vmware.com>
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Cc:     LKML <linux-kernel@vger.kernel.org>,
        Andrea Arcangeli <aarcange@redhat.com>,
        Andy Lutomirski <luto@kernel.org>,
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From:   Dave Hansen <dave.hansen@linux.intel.com>
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Date:   Fri, 23 Feb 2018 15:46:56 -0800
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On 02/22/2018 03:11 PM, Tom Lendacky wrote:
>> I don't think we can help out-of-tree modules getting this wrong.
>> They're OK if they use PAGE_KERNEL*, btw.
> You will probably need to change __default_kernel_pte_mask to be an
> EXPORT_SYMBOL instead of an EXPORT_SYMBOL_GPL for (some) out-of-tree
> modules.

As much as I detest missing an opportunity to kick non-GPL drivers in
the shins, I guess it is pretty cruel to break them for doing things
like vmap(PAGE_KERNEL).

I'll make it plain EXPORT_SYMBOL().