[PATCH 5.4 175/411] nvdimm: Allow overwrite in the presence of disabled dimms

[Greg Kroah-Hartman]

From: Dan Williams <dan.j.williams@xxxxxxxxx>

[ Upstream commit bb7bf697fed58eae9d3445944e457ab0de4da54f ]

It is not clear why the original implementation of overwrite support
required the dimm driver to be active before overwrite could proceed. In
fact that can lead to cases where the kernel retains an invalid cached
copy of the labels from before the overwrite. Unfortunately the kernel
has not only allowed that case, but enforced it.

Going forward, allow for overwrite to happen while the label area is
offline, and follow-on with updates to 'ndctl sanitize-dimm --overwrite'
to trigger the label area invalidation by default.

Cc: Vishal Verma <vishal.l.verma@xxxxxxxxx>
Cc: Dave Jiang <dave.jiang@xxxxxxxxx>
Cc: Ira Weiny <ira.weiny@xxxxxxxxx>
Cc: Jeff Moyer <jmoyer@xxxxxxxxxx>
Reported-by: Krzysztof Kensicki <krzysztof.kensicki@xxxxxxxxx>
Fixes: 7d988097c546 ("acpi/nfit, libnvdimm/security: Add security DSM overwrite support")
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/nvdimm/security.c | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/drivers/nvdimm/security.c b/drivers/nvdimm/security.c
index 35d265014e1e..0e23d8c27792 100644
--- a/drivers/nvdimm/security.c
+++ b/drivers/nvdimm/security.c
@@ -379,11 +379,6 @@ static int security_overwrite(struct nvdimm *nvdimm, unsigned int keyid)
 			|| !nvdimm->sec.flags)
 		return -EOPNOTSUPP;
 
-	if (dev->driver == NULL) {
-		dev_dbg(dev, "Unable to overwrite while DIMM active.\n");
-		return -EINVAL;
-	}
-
 	rc = check_security_state(nvdimm);
 	if (rc)
 		return rc;
-- 
2.35.1