| Message ID | 20190129165428.3931-3-jglisse@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | HMM updates for 5.1 | expand |
On 1/29/19 8:54 AM, jglisse@redhat.com wrote: > From: Jérôme Glisse <jglisse@redhat.com> > > Users of HMM might be using the snapshot information to do > preparatory step like dma mapping pages to a device before > checking for invalidation through hmm_vma_range_done() so > do not erase that information and assume users will do the > right thing. > > Signed-off-by: Jérôme Glisse <jglisse@redhat.com> > Cc: Andrew Morton <akpm@linux-foundation.org> > Cc: Ralph Campbell <rcampbell@nvidia.com> > Cc: John Hubbard <jhubbard@nvidia.com> > --- > mm/hmm.c | 6 ------ > 1 file changed, 6 deletions(-) > > diff --git a/mm/hmm.c b/mm/hmm.c > index b9f384ea15e9..74d69812d6be 100644 > --- a/mm/hmm.c > +++ b/mm/hmm.c > @@ -170,16 +170,10 @@ static int hmm_invalidate_range(struct hmm *hmm, bool device, > > spin_lock(&hmm->lock); > list_for_each_entry(range, &hmm->ranges, list) { > - unsigned long addr, idx, npages; > - > if (update->end < range->start || update->start >= range->end) > continue; > > range->valid = false; > - addr = max(update->start, range->start); > - idx = (addr - range->start) >> PAGE_SHIFT; > - npages = (min(range->end, update->end) - addr) >> PAGE_SHIFT; > - memset(&range->pfns[idx], 0, sizeof(*range->pfns) * npages); > } > spin_unlock(&hmm->lock); > > Seems harmless to me. I really cannot see how this could cause a problem, so you can add: Reviewed-by: John Hubbard <jhubbard@nvidia.com> thanks,
diff --git a/mm/hmm.c b/mm/hmm.c index b9f384ea15e9..74d69812d6be 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -170,16 +170,10 @@ static int hmm_invalidate_range(struct hmm *hmm, bool device, spin_lock(&hmm->lock); list_for_each_entry(range, &hmm->ranges, list) { - unsigned long addr, idx, npages; - if (update->end < range->start || update->start >= range->end) continue; range->valid = false; - addr = max(update->start, range->start); - idx = (addr - range->start) >> PAGE_SHIFT; - npages = (min(range->end, update->end) - addr) >> PAGE_SHIFT; - memset(&range->pfns[idx], 0, sizeof(*range->pfns) * npages); } spin_unlock(&hmm->lock);