On Tue, Apr 02, 2019 at 07:16:20AM +0800, Yang Shi wrote:

commit a7f40cfe3b7ada57af9b62fd28430eeb4a7cfcb7 upstream

When MPOL_MF_STRICT was specified and an existing page was already on a node that does not follow the policy, mbind() should return -EIO. But commit 6f4576e3687b ("mempolicy: apply page table walker on queue_pages_range()") broke the rule.

And commit c8633798497c ("mm: mempolicy: mbind and migrate_pages support thp migration") didn't return the correct value for THP mbind() too.

If MPOL_MF_STRICT is set, ignore vma_migratable() to make sure it reaches queue_pages_to_pte_range() or queue_pages_pmd() to check if an existing page was already on a node that does not follow the policy. And, non-migratable vma may be used, return -EIO too if MPOL_MF_MOVE or MPOL_MF_MOVE_ALL was specified.

Tested with https://github.com/metan-ucw/ltp/blob/master/testcases/kernel/syscalls/mbind...

[akpm@linux-foundation.org: tweak code comment] Link: http://lkml.kernel.org/r/1553020556-38583-1-git-send-email-yang.shi@linux.al... Fixes: 6f4576e3687b ("mempolicy: apply page table walker on queue_pages_range()") Signed-off-by: Yang Shi yang.shi@linux.alibaba.com Signed-off-by: Oscar Salvador osalvador@suse.de Reported-by: Cyril Hrubis chrubis@suse.cz Suggested-by: Kirill A. Shutemov kirill@shutemov.name Acked-by: Rafael Aquini aquini@redhat.com Reviewed-by: Oscar Salvador osalvador@suse.de Acked-by: David Rientjes rientjes@google.com Cc: Vlastimil Babka vbabka@suse.cz Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org

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mm/mempolicy.c | 40 +++++++++++++++++++++++++++++++++------- 1 file changed, 33 insertions(+), 7 deletions(-)

All 3 of these now queued up, thanks.

greg k-h