From: Dan Williams Date: Thu, 10 Mar 2022 03:49:21 +0000 (-0800) Subject: nvdimm/region: Fix default alignment for small regions X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=be8ab90a3a77d0a7471655a719cce0ba1fcb0450;p=linux.git nvdimm/region: Fix default alignment for small regions [ 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 Link: https://lore.kernel.org/r/164688416128.2879318.17890707310125575258.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams Signed-off-by: Sasha Levin --- diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c index 9ccf3d6087993..70ad891a76bae 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)