On Fri, Oct 12, 2018 at 01:35:19PM -0400, Jerome Glisse wrote: > On Fri, Oct 12, 2018 at 01:24:22PM -0400, Andrea Arcangeli wrote: > > Hello, > > > > On Fri, Oct 12, 2018 at 12:20:54PM -0400, Zi Yan wrote: > > > On 12 Oct 2018, at 12:09, jglisse@xxxxxxxxxx wrote: > > > > > > > From: Jérôme Glisse <jglisse@xxxxxxxxxx> > > > > > > > > Inside set_pmd_migration_entry() we are holding page table locks and > > > > thus we can not sleep so we can not call invalidate_range_start/end() > > > > > > > > So remove call to mmu_notifier_invalidate_range_start/end() and add > > > > call to mmu_notifier_invalidate_range(). Note that we are already > > > > Why the call to mmu_notifier_invalidate_range if we're under > > range_start and followed by range_end? (it's not _range_only_end, if > > it was _range_only_end the above would be needed) > > I wanted to be extra safe and accept to over invalidate. You are right > that it is not strictly necessary. I am fine with removing it. If it's superfluous, I'd generally prefer strict code unless there's a very explicit comment about it that says it's actually superfluous. Otherwise after a while we don't know why it was added there. > We can remove it. Should i post a v2 without it ? That's fine with me yes. Thanks, Andrea
