On 10/29/25 00:01, Claudio Imbrenda wrote: > For hugetlbs, gmap puds have the present bit set. For normal puds > (which point to ptes), the bit is not set. This is in contrast to the > normal userspace puds, which always have the bit set for present pmds. > > This causes issues when ___pte_offset_map() is modified to only check > for the present bit. > > The solution to the problem is simply to always set the present bit for > present gmap pmds. > > Signed-off-by: Claudio Imbrenda <[email protected]> > Link: > https://lore.kernel.org/lkml/[email protected]/ > Tested-by: Christian Borntraeger <[email protected]> > Acked-by: Christian Borntraeger <[email protected]> > --- > arch/s390/mm/gmap.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c > index 8ff6bba107e8..22c448b32340 100644 > --- a/arch/s390/mm/gmap.c > +++ b/arch/s390/mm/gmap.c > @@ -599,8 +599,9 @@ int __gmap_link(struct gmap *gmap, unsigned long gaddr, > unsigned long vmaddr) > | _SEGMENT_ENTRY_GMAP_UC > | _SEGMENT_ENTRY; > } else > - *table = pmd_val(*pmd) & > - _SEGMENT_ENTRY_HARDWARE_BITS; > + *table = (pmd_val(*pmd) & > + _SEGMENT_ENTRY_HARDWARE_BITS) > + | _SEGMENT_ENTRY; > } > } else if (*table & _SEGMENT_ENTRY_PROTECT && > !(pmd_val(*pmd) & _SEGMENT_ENTRY_PROTECT)) {
Acked-by: Balbir Singh <[email protected]>
