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author | Miaohe Lin <linmiaohe@huawei.com> | 2022-08-16 16:05:53 +0300 |
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committer | Andrew Morton <akpm@linux-foundation.org> | 2022-09-12 06:25:55 +0300 |
commit | 3aa4ed8040e1535d95c03cef8b52cf11bf0d8546 (patch) | |
tree | e63c37c557b8f1a5781c7970043d46b43c1590fd /arch/ia64 | |
parent | 01088a603660dfa240ba3331f0a49a3e9797cad1 (diff) | |
download | linux-3aa4ed8040e1535d95c03cef8b52cf11bf0d8546.tar.xz |
mm/hugetlb: make detecting shared pte more reliable
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>
Diffstat (limited to 'arch/ia64')
0 files changed, 0 insertions, 0 deletions