In preparation for removing BLK aperture support the NVDIMM unit tests discovered that the default alignment can be set higher than the capacity of the region. Fall back to PAGE_SIZE in that case. Given this has not been seen in the wild, elide notifying -stable. Fixes: 2522afb86a8c ("libnvdimm/region: Introduce an 'align' attribute") Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx> --- drivers/nvdimm/region_devs.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c index 9ccf3d608799..70ad891a76ba 100644 --- a/drivers/nvdimm/region_devs.c +++ b/drivers/nvdimm/region_devs.c @@ -1025,6 +1025,9 @@ static unsigned long default_align(struct nd_region *nd_region) } } + if (nd_region->ndr_size < MEMREMAP_COMPAT_ALIGN_MAX) + align = PAGE_SIZE; + mappings = max_t(u16, 1, nd_region->ndr_mappings); div_u64_rem(align, mappings, &remainder); if (remainder)