From b62cc6fdd793eaac50e4191c8637ffff9e9574d6 Mon Sep 17 00:00:00 2001
From: Dan Williams <dan.j.williams@intel.com>
Date: Mon, 18 Jun 2018 10:07:35 -0700
Subject: [PATCH] libnvdimm, pmem: Fix memcpy_mcsafe() return code handling in
 nsio_rw_bytes()
Git-commit: b62cc6fdd793eaac50e4191c8637ffff9e9574d6
Patch-mainline: v4.18-rc5
References: bsc#1098782

Commit 60622d68227d "x86/asm/memcpy_mcsafe: Return bytes remaining"
converted callers of memcpy_mcsafe() to expect a positive 'bytes
remaining' value rather than a negative error code. The nsio_rw_bytes()
conversion failed to return success. The failure is benign in that
nsio_rw_bytes() will end up writing back what it just read.

Fixes: 60622d68227d ("x86/asm/memcpy_mcsafe: Return bytes remaining")
Cc: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Jan Kara <jack@suse.cz>

---
 drivers/nvdimm/claim.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/nvdimm/claim.c b/drivers/nvdimm/claim.c
index 2e96b34bc936..fb667bf469c7 100644
--- a/drivers/nvdimm/claim.c
+++ b/drivers/nvdimm/claim.c
@@ -278,6 +278,7 @@ static int nsio_rw_bytes(struct nd_namespace_common *ndns,
 			return -EIO;
 		if (memcpy_mcsafe(buf, nsio->addr + offset, size) != 0)
 			return -EIO;
+		return 0;
 	}
 
 	if (unlikely(is_bad_pmem(&nsio->bb, sector, sz_align))) {
-- 
2.16.4