Testing the dax-device autodetect support revealed a probe failure with the following result: dax0.1: bad offset: 0x8200000 dax disabled The original pfn-device implementation inferred the alignment from ilog2(offset), now that the alignment is explicit the is_power_of_2() needs replacing with a real sanity check against the recorded alignment. Otherwise the alignment check is useless in the implicit case and only the minimum size of the offset matters. This self-consistency check is further validated by the probe path that will re-check that the offset is large enough to contain all the metadata required to enable the device. Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx> --- drivers/nvdimm/pfn_devs.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/nvdimm/pfn_devs.c b/drivers/nvdimm/pfn_devs.c index 816cd9828ca5..33c97076ddf0 100644 --- a/drivers/nvdimm/pfn_devs.c +++ b/drivers/nvdimm/pfn_devs.c @@ -416,6 +416,7 @@ int nd_pfn_validate(struct nd_pfn *nd_pfn, const char *sig) return -ENODEV; } + nd_pfn->align = le32_to_cpu(pfn_sb->align); if (nd_pfn->align > nvdimm_namespace_capacity(ndns)) { dev_err(&nd_pfn->dev, "alignment: %lx exceeds capacity %llx\n", nd_pfn->align, nvdimm_namespace_capacity(ndns)); @@ -436,8 +437,8 @@ int nd_pfn_validate(struct nd_pfn *nd_pfn, const char *sig) return -EBUSY; } - nd_pfn->align = le32_to_cpu(pfn_sb->align); - if (!is_power_of_2(offset) || offset < PAGE_SIZE) { + if ((nd_pfn->align && !IS_ALIGNED(offset, nd_pfn->align)) + || !IS_ALIGNED(offset, PAGE_SIZE)) { dev_err(&nd_pfn->dev, "bad offset: %#llx dax disabled\n", offset); return -ENXIO; -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html