3aa4ed8040
If the pagetables are shared, we shouldn't copy or take references. Since src could have unshared and dst shares with another vma, huge_pte_none() is thus used to determine whether dst_pte is shared. But this check isn't reliable. A shared pte could have pte none in pagetable in fact. The page count of ptep page should be checked here in order to reliably determine whether pte is shared. [lukas.bulwahn@gmail.com: remove unused local variable dst_entry in copy_hugetlb_page_range()] Link: https://lkml.kernel.org/r/20220822082525.26071-1-lukas.bulwahn@gmail.com Link: https://lkml.kernel.org/r/20220816130553.31406-7-linmiaohe@huawei.com Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.