On Wed, Jan 15, 2014 at 11:40:34AM +0200, Mike Rapoport wrote: > Commit 6bdb913f0a70a4dfb7f066fb15e2d6f960701d00 (mm: wrap calls to > set_pte_at_notify with invalidate_range_start and invalidate_range_end) > breaks semantics of set_pte_at_notify. When calls to set_pte_at_notify > are wrapped with mmu_notifier_invalidate_range_start and > mmu_notifier_invalidate_range_end, KVM zaps pte during > mmu_notifier_invalidate_range_start callback and set_pte_at_notify has > no spte to update and therefore it's called for nothing. > > As Andrea suggested (1), the problem is resolved by calling > mmu_notifier_invalidate_page after PT lock has been released and only > for mmu_notifiers that do not implement change_ptr callback. > > (1) http://thread.gmane.org/gmane.linux.kernel.mm/111710/focus=111711 > > Reported-by: Izik Eidus <izik.eidus@xxxxxxxxxxxxxxxxxx> > Signed-off-by: Mike Rapoport <mike.rapoport@xxxxxxxxxxxxxxxxxx> > Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx> > Cc: Haggai Eran <haggaie@xxxxxxxxxxxx> > Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> > --- > include/linux/mmu_notifier.h | 31 ++++++++++++++++++++++++++----- > kernel/events/uprobes.c | 12 ++++++------ > mm/ksm.c | 15 +++++---------- > mm/memory.c | 14 +++++--------- > mm/mmu_notifier.c | 24 ++++++++++++++++++++++-- > 5 files changed, 64 insertions(+), 32 deletions(-) Reviewed-by: Andrea Arcangeli <aarcange@xxxxxxxxxx> Thanks! Andrea -- 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>