From: Dan Williams dan.j.williams@intel.com
[ Upstream commit d9d290d7e659e9db3e4518040cc18b97f5535f4a ]
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") Reviewed-by: Christoph Hellwig hch@lst.de Link: https://lore.kernel.org/r/164688416128.2879318.17890707310125575258.stgit@dw... Signed-off-by: Dan Williams dan.j.williams@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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)