[src/trunk]: src/sys/dev If config_cfattach_detach() returns an error, handle...

[pgoyette <pgoyette%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/f28c972a7957
branches:  trunk
changeset: 828519:f28c972a7957
user:      pgoyette <pgoyette%NetBSD.org@localhost>
date:      Sun Dec 17 22:09:47 2017 +0000

description:
If config_cfattach_detach() returns an error, handle it instead of
ignoring.  Otherwise the mutex will get destroyed and we'll unload
the module, and any active users will eventually cause a panic.

Noted by code inspection.

XXX pullup to netbsd-8

diffstat:

 sys/dev/fss.c |  13 ++++++++++---
 1 files changed, 10 insertions(+), 3 deletions(-)

diffs (34 lines):

diff -r a52034a27f8d -r f28c972a7957 sys/dev/fss.c
--- a/sys/dev/fss.c     Sun Dec 17 21:57:11 2017 +0000
+++ b/sys/dev/fss.c     Sun Dec 17 22:09:47 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: fss.c,v 1.99 2017/10/28 03:47:24 riastradh Exp $       */
+/*     $NetBSD: fss.c,v 1.100 2017/12/17 22:09:47 pgoyette Exp $       */
 
 /*-
  * Copyright (c) 2003 The NetBSD Foundation, Inc.
@@ -36,7 +36,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: fss.c,v 1.99 2017/10/28 03:47:24 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: fss.c,v 1.100 2017/12/17 22:09:47 pgoyette Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -1321,7 +1321,14 @@
                            &fss_cdevsw, &fss_cmajor);
                        break;
                }
-               config_cfdriver_detach(&fss_cd);
+               error = config_cfdriver_detach(&fss_cd);
+               if (error) {
+                       devsw_attach(fss_cd.cd_name,
+                           &fss_bdevsw, &fss_bmajor, &fss_cdevsw, &fss_cmajor);
+                       devsw_attach(fss_cd.cd_name, &fss_bdevsw, &fss_bmajor,
+                           &fss_cdevsw, &fss_cmajor);
+                       break;
+               }
                mutex_destroy(&fss_device_lock);
                break;