| Message ID | 20200824083128.12684-1-alistair@popple.id.au (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/2] mm/migrate: Fixup setting UFFD_WP flag | expand |
On Mon, Aug 24, 2020 at 06:31:27PM +1000, Alistair Popple wrote: > Commit f45ec5ff16a75 ("userfaultfd: wp: support swap and page > migration") introduced support for tracking the uffd wp bit during page > migration. However the non-swap PTE variant was used to set the flag for > zone device private pages which are a type of swap page. > > This leads to corruption of the swap offset if the original PTE has the > uffd_wp flag set. > > Fixes: f45ec5ff16a75 ("userfaultfd: wp: support swap and page migration") > Signed-off-by: Alistair Popple <alistair@popple.id.au> > Cc: stable@vger.kernel.org > --- > mm/migrate.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/migrate.c b/mm/migrate.c > index 34a842a8eb6a..ddb64253fe3e 100644 > --- a/mm/migrate.c > +++ b/mm/migrate.c > @@ -251,7 +251,7 @@ static bool remove_migration_pte(struct page *page, struct vm_area_struct *vma, > entry = make_device_private_entry(new, pte_write(pte)); > pte = swp_entry_to_pte(entry); > if (pte_swp_uffd_wp(*pvmw.pte)) > - pte = pte_mkuffd_wp(pte); > + pte = pte_swp_mkuffd_wp(pte); > } > } Looks correct... thanks! Reviewed-by: Peter Xu <peterx@redhat.com>
diff --git a/mm/migrate.c b/mm/migrate.c index 34a842a8eb6a..ddb64253fe3e 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -251,7 +251,7 @@ static bool remove_migration_pte(struct page *page, struct vm_area_struct *vma, entry = make_device_private_entry(new, pte_write(pte)); pte = swp_entry_to_pte(entry); if (pte_swp_uffd_wp(*pvmw.pte)) - pte = pte_mkuffd_wp(pte); + pte = pte_swp_mkuffd_wp(pte); } }
Commit f45ec5ff16a75 ("userfaultfd: wp: support swap and page migration") introduced support for tracking the uffd wp bit during page migration. However the non-swap PTE variant was used to set the flag for zone device private pages which are a type of swap page. This leads to corruption of the swap offset if the original PTE has the uffd_wp flag set. Fixes: f45ec5ff16a75 ("userfaultfd: wp: support swap and page migration") Signed-off-by: Alistair Popple <alistair@popple.id.au> Cc: stable@vger.kernel.org --- mm/migrate.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)