On most architectures, def_flags is either 0 or VM_LOCKED depending on whether mlockall(MCL_FUTURE) was called. However, this is not an absolute rule as kvm support on s390 may set the VM_NOHUGEPAGE flag in def_flags. We don't want mlockall to clear that. Signed-off-by: Michel Lespinasse <walken@xxxxxxxxxx> --- mm/mlock.c | 5 +++-- 1 files changed, 3 insertions(+), 2 deletions(-) diff --git a/mm/mlock.c b/mm/mlock.c index f0b9ce572fc7..a2ee45c030fa 100644 --- a/mm/mlock.c +++ b/mm/mlock.c @@ -517,10 +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; + unsigned int def_flags; + def_flags = current->mm->def_flags & ~VM_LOCKED; if (flags & MCL_FUTURE) - def_flags = VM_LOCKED; + def_flags |= VM_LOCKED; current->mm->def_flags = def_flags; if (flags == MCL_FUTURE) goto out; -- 1.7.7.3 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>