Re: [PATCH hmm 4/8] mm/hmm: add missing pfns set to hmm_vma_walk_pmd()

On 3/11/20 11:35 AM, Jason Gunthorpe wrote:

From: Jason Gunthorpe jgg@mellanox.com

All success exit paths from the walker functions must set the pfns array.

A migration entry with no required fault is a HMM_PFN_NONE return, just like the pte case.

Fixes: d08faca018c4 ("mm/hmm: properly handle migration pmd") Signed-off-by: Jason Gunthorpe jgg@mellanox.com

Reviewed-by: Ralph Campbell rcampbell@nvidia.com

---

mm/hmm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/hmm.c b/mm/hmm.c index 32dcbfd3908315..5f5ccf13dd1e85 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -394,7 +394,7 @@ static int hmm_vma_walk_pmd(pmd_t *pmdp, pmd_migration_entry_wait(walk->mm, pmdp); return -EBUSY; }

• return 0;
  

• return hmm_pfns_fill(start, end, range, HMM_PFN_NONE);
  

  } else if (!pmd_present(pmd)) return hmm_pfns_fill(start, end, range, HMM_PFN_ERROR);