Module Name: src
Committed By: christos
Date: Fri Sep 7 13:24:14 UTC 2018
Modified Files:
src/sys/net: if.c
Log Message:
Flip the order of free'ing things to avoid crash (from ozaki-r). Tested
with a month's uptime. Used to crash once a week.
To generate a diff of this commit:
cvs rdiff -u -r1.435 -r1.436 src/sys/net/if.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/net/if.c
diff -u src/sys/net/if.c:1.435 src/sys/net/if.c:1.436
--- src/sys/net/if.c:1.435 Thu Sep 6 02:42:00 2018
+++ src/sys/net/if.c Fri Sep 7 09:24:14 2018
@@ -1,4 +1,4 @@
-/* $NetBSD: if.c,v 1.435 2018/09/06 06:42:00 maxv Exp $ */
+/* $NetBSD: if.c,v 1.436 2018/09/07 13:24:14 christos Exp $ */
/*-
* Copyright (c) 1999, 2000, 2001, 2008 The NetBSD Foundation, Inc.
@@ -90,7 +90,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if.c,v 1.435 2018/09/06 06:42:00 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if.c,v 1.436 2018/09/07 13:24:14 christos Exp $");
#if defined(_KERNEL_OPT)
#include "opt_inet.h"
@@ -1322,6 +1322,18 @@ if_detach(struct ifnet *ifp)
if_deactivate(ifp);
IFNET_UNLOCK(ifp);
+ /*
+ * Unlink from the list and wait for all readers to leave
+ * from pserialize read sections. Note that we can't do
+ * psref_target_destroy here. See below.
+ */
+ IFNET_GLOBAL_LOCK();
+ ifindex2ifnet[ifp->if_index] = NULL;
+ TAILQ_REMOVE(&ifnet_list, ifp, if_list);
+ IFNET_WRITER_REMOVE(ifp);
+ pserialize_perform(ifnet_psz);
+ IFNET_GLOBAL_UNLOCK();
+
if (ifp->if_slowtimo != NULL && ifp->if_slowtimo_ch != NULL) {
ifp->if_slowtimo = NULL;
callout_halt(ifp->if_slowtimo_ch, NULL);
@@ -1453,14 +1465,10 @@ restart:
}
}
- /* Wait for all readers to drain before freeing. */
- IFNET_GLOBAL_LOCK();
- ifindex2ifnet[ifp->if_index] = NULL;
- TAILQ_REMOVE(&ifnet_list, ifp, if_list);
- IFNET_WRITER_REMOVE(ifp);
- pserialize_perform(ifnet_psz);
- IFNET_GLOBAL_UNLOCK();
-
+ /*
+ * Must be done after the above pr_purgeif because if_psref may be
+ * still used in pr_purgeif.
+ */
psref_target_destroy(&ifp->if_psref, ifnet_psref_class);
PSLIST_ENTRY_DESTROY(ifp, if_pslist_entry);
