Re: [PATCH v5 2/6] userfaultfd: use kmap_local_page() in copy_huge_page_from_user()

Mike Kravetz
2023-04-06T21:33:11Z

On 03/31/23 17:39, Peng Zhang wrote:
> From: ZhangPeng <zhangpeng362@huawei.com>
>
> kmap() and kmap_atomic() are being deprecated in favor of
> kmap_local_page() which is appropriate for any thread local context.[1]
>
> Let's replace the kmap() and kmap_atomic() with kmap_local_page() in
> copy_huge_page_from_user(). When allow_pagefault is false, disable page
> faults to prevent potential deadlock.[2]
>
> [1] https://lore.kernel.org/all/20220813220034.806698-1-ira.weiny@intel.com/
> [2] https://lkml.kernel.org/r/20221025220136.2366143-1-ira.weiny@intel.com
>
> Signed-off-by: ZhangPeng <zhangpeng362@huawei.com>
> ---
> mm/memory.c | 14 ++++++--------
> 1 file changed, 6 insertions(+), 8 deletions(-)

Thanks,

Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
--
Mike Kravetz