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Subject: Re: [PATCH 05/23] x86, kaiser: unmap kernel from userspace page
 tables (core patch)
To: Hanjun Guo <guohanjun@huawei.com>, Jiri Kosina <jikos@kernel.org>
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On 01/05/2018 10:28 PM, Hanjun Guo wrote:
>> +
>>  	p4d = p4d_alloc(&tboot_mm, pgd, vaddr);
> Seems pgd will be re-set after p4d_alloc(), so should
> we put the code behind (or after pud_alloc())?

<sigh> Yes, it has to go below where the PGD actually gets set which is
after pud_alloc().  You can put it anywhere later in the function.