From 1974d7a40e0a56a01f05e03e22970bd4d042786a Mon Sep 17 00:00:00 2001
From: D Scott Phillips <scottph@FreeBSD.org>
Date: Mon, 19 Aug 2019 17:51:06 +0000
Subject: [PATCH] Don't set the string "unknown" as a device's location_str

Return an empty string when the location is unknown instead of the
string "unknown". This ensures that all location entries are of
the form key=val.

Suggested by:	imp
Approved by:	jhb (mentor)
MFC after:	1 week
Sponsored by:	Intel Corporation
Differential Revision:	https://reviews.freebsd.org/D21326
---
 sys/dev/acpica/acpi.c   | 2 +-
 sys/dev/nvdimm/nvdimm.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/sys/dev/acpica/acpi.c b/sys/dev/acpica/acpi.c
index c6b0796de478..382d139617de 100644
--- a/sys/dev/acpica/acpi.c
+++ b/sys/dev/acpica/acpi.c
@@ -866,7 +866,7 @@ acpi_child_location_str_method(device_t cbdev, device_t child, char *buf,
                 strlcat(buf, buf2, buflen);
         }
     } else {
-        snprintf(buf, buflen, "unknown");
+        snprintf(buf, buflen, "");
     }
     return (0);
 }
diff --git a/sys/dev/nvdimm/nvdimm.c b/sys/dev/nvdimm/nvdimm.c
index 5c6b6ee6dc72..e7d13cbf20f7 100644
--- a/sys/dev/nvdimm/nvdimm.c
+++ b/sys/dev/nvdimm/nvdimm.c
@@ -571,7 +571,7 @@ nvdimm_root_child_location_str(device_t dev, device_t child, char *buf,
 	if (handle != NULL)
 		res = snprintf(buf, buflen, "handle=%s", acpi_name(handle));
 	else
-		res = snprintf(buf, buflen, "unknown");
+		res = snprintf(buf, buflen, "");
 
 	if (res >= buflen)
 		return (EOVERFLOW);