acpi, nfit, libnvdimm: fix interleave set cookie calculation (64-bit comparison)

While reviewing the -stable patch for commit 86ef58a4e3 "nfit,
libnvdimm: fix interleave set cookie calculation" Ben noted:

    "This is returning an int, thus it's effectively doing a 32-bit
     comparison and not the 64-bit comparison you say is needed."

Update the compare operation to be immune to this integer demotion problem.

Cc: <stable@vger.kernel.org>
Cc: Nicholas Moulin <nicholas.w.moulin@linux.intel.com>
Fixes: 86ef58a4e3 ("nfit, libnvdimm: fix interleave set cookie calculation")
Reported-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This commit is contained in:
Dan Williams 2017-03-27 21:53:38 -07:00
parent c02ed2e75e
commit b03b99a329

View File

@ -1617,7 +1617,11 @@ static int cmp_map(const void *m0, const void *m1)
const struct nfit_set_info_map *map0 = m0;
const struct nfit_set_info_map *map1 = m1;
return map0->region_offset - map1->region_offset;
if (map0->region_offset < map1->region_offset)
return -1;
else if (map0->region_offset > map1->region_offset)
return 1;
return 0;
}
/* Retrieve the nth entry referencing this spa */