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Date:   Mon, 7 Aug 2023 17:29:38 -0700
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Subject: Re: [PATCH v2 04/32] mm/pgtable: allow pte_offset_map[_lock]() to
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To:     Matthew Wilcox <willy@infradead.org>,
        Yongqin Liu <yongqin.liu@linaro.org>
CC:     Hugh Dickins <hughd@google.com>,
        Andrew Morton <akpm@linux-foundation.org>,
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From:   John Hubbard <jhubbard@nvidia.com>
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On 8/5/23 10:07, Matthew Wilcox wrote:
...
>> Sorry, I am not able to give any explanation here,
>> I am not familiar with the pvrsrvkm source, I just use it to have one
>> working AOSP build.
>>
>> here is the source file where pte_offset_map_lock is called,
>>      https://android-git.linaro.org/kernel/omap-modules.git/tree/pvr/services4/srvkm/env/linux/osfunc.c?h=android-mainline#n3508
>> in case you could know something with a quick look.
> 
> Isn't this just get_user_pages()?


Or even just follow_page(), which looks like a nearly perfect drop-in
replacement, especially since that android link also says, "The page in
question must be present (i.e. no fault handling required)".


thanks,
-- 
John Hubbard
NVIDIA