From ca94915779c76402b40445d35bcbe0dfd60cec6d Mon Sep 17 00:00:00 2001
From: Alasdair Kergon <agk@redhat.com>
Date: Fri, 1 Nov 2002 16:16:42 +0000
Subject: [PATCH] Improve missing-kernel-driver error message.

---
 libdm/ioctl/libdevmapper.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/libdm/ioctl/libdevmapper.c b/libdm/ioctl/libdevmapper.c
index b33e53306..028e034c6 100644
--- a/libdm/ioctl/libdevmapper.c
+++ b/libdm/ioctl/libdevmapper.c
@@ -351,7 +351,8 @@ int dm_task_run(struct dm_task *dmt)
 	snprintf(control, sizeof(control), "%s/control", dm_dir());
 
 	if ((fd = open(control, O_RDWR)) < 0) {
-		log_error("Couldn't open device-mapper control device");
+		log_error("%s: open failed: %s", control, strerror(errno));
+		log_error("Is device-mapper driver missing from kernel?");
 		goto bad;
 	}