diff options
| author | Gerald Schaefer <gerald.schaefer@de.ibm.com> | 2013-02-12 13:46:20 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-02-12 14:34:00 -0800 |
| commit | 9977f0f164d46613288e0b5778eae500dfe06f31 (patch) | |
| tree | d854a1cc5c422107028ed9dfab4360a9b5d40395 /mm/mlock.c | |
| parent | 3399cfb5df9594495b876d1843a7165f77366b2b (diff) | |
| download | lwn-9977f0f164d46613288e0b5778eae500dfe06f31.tar.gz lwn-9977f0f164d46613288e0b5778eae500dfe06f31.zip | |
mm: don't overwrite mm->def_flags in do_mlockall()
With commit 8e72033f2a48 ("thp: make MADV_HUGEPAGE check for
mm->def_flags") the VM_NOHUGEPAGE flag may be set on s390 in
mm->def_flags for certain processes, to prevent future thp mappings.
This would be overwritten by do_mlockall(), which sets it back to 0 with
an optional VM_LOCKED flag set.
To fix this, instead of overwriting mm->def_flags in do_mlockall(), only
the VM_LOCKED flag should be set or cleared.
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Reported-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/mlock.c')
| -rw-r--r-- | mm/mlock.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/mm/mlock.c b/mm/mlock.c index f0b9ce572fc7..c9bd528b01d2 100644 --- a/mm/mlock.c +++ b/mm/mlock.c @@ -517,11 +517,11 @@ SYSCALL_DEFINE2(munlock, unsigned long, start, size_t, len) static int do_mlockall(int flags) { struct vm_area_struct * vma, * prev = NULL; - unsigned int def_flags = 0; if (flags & MCL_FUTURE) - def_flags = VM_LOCKED; - current->mm->def_flags = def_flags; + current->mm->def_flags |= VM_LOCKED; + else + current->mm->def_flags &= ~VM_LOCKED; if (flags == MCL_FUTURE) goto out; |