]> git.proxmox.com Git - mirror_ubuntu-kernels.git/commit
mm: mempolicy: make mbind() return -EIO when MPOL_MF_STRICT is specified
authorYang Shi <yang.shi@linux.alibaba.com>
Fri, 29 Mar 2019 03:43:55 +0000 (20:43 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 29 Mar 2019 17:01:37 +0000 (10:01 -0700)
commita7f40cfe3b7ada57af9b62fd28430eeb4a7cfcb7
tree6a4f0cd417d878f5a6e7b04d4db1a5305590bcf3
parenta953e7721fa9999fd628885ed451e16641a23d1e
mm: mempolicy: make mbind() return -EIO when MPOL_MF_STRICT is specified

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/mbind02.c

[akpm@linux-foundation.org: tweak code comment]
Link: http://lkml.kernel.org/r/1553020556-38583-1-git-send-email-yang.shi@linux.alibaba.com
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>
mm/mempolicy.c