[src/trunk]: src/sys/kern autoconf(9): Take kernel lock on various entries in...

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

details:   https://anonhg.NetBSD.org/src/rev/3b8d9f5c8a19
branches:  trunk
changeset: 379609:3b8d9f5c8a19
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Sat Jun 12 12:11:49 2021 +0000

description:
autoconf(9): Take kernel lock on various entries into autoconf.

Most of autoconf still tacitly assumes the kernel lock is held.

diffstat:

 sys/kern/subr_autoconf.c |  39 ++++++++++++++++++++++++++++-----------
 1 files changed, 28 insertions(+), 11 deletions(-)

diffs (101 lines):

diff -r c7a6735f3ca8 -r 3b8d9f5c8a19 sys/kern/subr_autoconf.c
--- a/sys/kern/subr_autoconf.c  Sat Jun 12 12:11:38 2021 +0000
+++ b/sys/kern/subr_autoconf.c  Sat Jun 12 12:11:49 2021 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: subr_autoconf.c,v 1.280 2021/04/28 03:21:57 thorpej Exp $ */
+/* $NetBSD: subr_autoconf.c,v 1.281 2021/06/12 12:11:49 riastradh Exp $ */
 
 /*
  * Copyright (c) 1996, 2000 Christopher G. Demetriou
@@ -79,7 +79,7 @@
 #define        __SUBR_AUTOCONF_PRIVATE /* see <sys/device.h> */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: subr_autoconf.c,v 1.280 2021/04/28 03:21:57 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: subr_autoconf.c,v 1.281 2021/06/12 12:11:49 riastradh Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_ddb.h"
@@ -1285,11 +1285,15 @@ device_t
 config_rootfound(const char *rootname, void *aux)
 {
        cfdata_t cf;
-
+       device_t dev = NULL;
+
+       KERNEL_LOCK(1, NULL);
        if ((cf = config_rootsearch(NULL, rootname, aux)) != NULL)
-               return config_attach(ROOT, cf, aux, NULL, CFARG_EOL);
-       aprint_error("root device %s not configured\n", rootname);
-       return NULL;
+               dev = config_attach(ROOT, cf, aux, NULL, CFARG_EOL);
+       else
+               aprint_error("root device %s not configured\n", rootname);
+       KERNEL_UNLOCK_ONE(NULL);
+       return dev;
 }
 
 /* just like sprintf(buf, "%d") except that it works from the end */
@@ -2046,8 +2050,10 @@ config_detach_all(int how)
        bool progress = false;
        int flags;
 
+       KERNEL_LOCK(1, NULL);
+
        if ((how & (RB_NOSYNC|RB_DUMP)) != 0)
-               return false;
+               goto out;
 
        if ((how & RB_POWERDOWN) == RB_POWERDOWN)
                flags = DETACH_SHUTDOWN | DETACH_POWEROFF;
@@ -2063,6 +2069,8 @@ config_detach_all(int how)
                } else
                        aprint_debug("failed.");
        }
+
+out:   KERNEL_UNLOCK_ONE(NULL);
        return progress;
 }
 
@@ -2286,6 +2294,9 @@ int
 config_finalize_register(device_t dev, int (*fn)(device_t))
 {
        struct finalize_hook *f;
+       int error = 0;
+
+       KERNEL_LOCK(1, NULL);
 
        /*
         * If finalization has already been done, invoke the
@@ -2294,13 +2305,15 @@ config_finalize_register(device_t dev, i
        if (config_finalize_done) {
                while ((*fn)(dev) != 0)
                        /* loop */ ;
-               return 0;
+               goto out;
        }
 
        /* Ensure this isn't already on the list. */
        TAILQ_FOREACH(f, &config_finalize_list, f_list) {
-               if (f->f_func == fn && f->f_dev == dev)
-                       return EEXIST;
+               if (f->f_func == fn && f->f_dev == dev) {
+                       error = EEXIST;
+                       goto out;
+               }
        }
 
        f = kmem_alloc(sizeof(*f), KM_SLEEP);
@@ -2308,7 +2321,11 @@ config_finalize_register(device_t dev, i
        f->f_dev = dev;
        TAILQ_INSERT_TAIL(&config_finalize_list, f, f_list);
 
-       return 0;
+       /* Success!  */
+       error = 0;
+
+out:   KERNEL_UNLOCK_ONE(NULL);
+       return error;
 }
 
 void