[PATCH 0/1] mm/hugetlb.c: teach follow_hugetlb_page() to handle FOLL_NOWAIT

From: Andrea Arcangeli
Date: Tue Jan 08 2019 - 21:02:25 EST


Hello,

this fixes a regression that resurfaced in hugetlbfs code after we
fixed it for the core VM a few months ago. This is only reproducible
doing postcopy live migration of KVM (the only user of FOLL_NOWAIT) if
backed by hugetlbfs memory. It's unrelated to userfaultfd, but
userfaultfd reproduces it easily because it's an heavy user of
VM_FAULT_RETRY retvals.

Thanks,
Andrea

Andrea Arcangeli (1):
mm/hugetlb.c: teach follow_hugetlb_page() to handle FOLL_NOWAIT

mm/hugetlb.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)