Author: jhb
Date: Mon Jan 24 22:21:58 2011
New Revision: 217805
URL: http://svn.freebsd.org/changeset/base/217805
Log:
Fix a LOR by dropping the global ifnet locks while allocating a new ifnet
table in if_grow(). The order of the SYSINIT's for ifnet state were swapped
so that the various locks were initialized before being used.
Reviewed by: pluknet, bz
MFC after: 2 weeks
Modified:
head/sys/net/if.c
Modified: head/sys/net/if.c
==============================================================================
--- head/sys/net/if.c Mon Jan 24 21:04:32 2011 (r217804)
+++ head/sys/net/if.c Mon Jan 24 22:21:58 2011 (r217805)
@@ -266,6 +266,7 @@ ifindex_alloc_locked(u_short *idxp)
IFNET_WLOCK_ASSERT();
+retry:
/*
* Try to find an empty slot below V_if_index. If we fail, take the
* next slot.
@@ -278,10 +279,12 @@ ifindex_alloc_locked(u_short *idxp)
/* Catch if_index overflow. */
if (idx < 1)
return (ENOSPC);
+ if (idx >= V_if_indexlim) {
+ if_grow();
+ goto retry;
+ }
if (idx > V_if_index)
V_if_index = idx;
- if (V_if_index >= V_if_indexlim)
- if_grow();
*idxp = idx;
return (0);
}
@@ -351,10 +354,12 @@ vnet_if_init(const void *unused __unused
TAILQ_INIT(&V_ifnet);
TAILQ_INIT(&V_ifg_head);
+ IFNET_WLOCK();
if_grow(); /* create initial table */
+ IFNET_WUNLOCK();
vnet_if_clone_init();
}
-VNET_SYSINIT(vnet_if_init, SI_SUB_INIT_IF, SI_ORDER_FIRST, vnet_if_init,
+VNET_SYSINIT(vnet_if_init, SI_SUB_INIT_IF, SI_ORDER_SECOND, vnet_if_init,
NULL);
/* ARGSUSED*/
@@ -365,7 +370,7 @@ if_init(void *dummy __unused)
IFNET_LOCK_INIT();
if_clone_init();
}
-SYSINIT(interfaces, SI_SUB_INIT_IF, SI_ORDER_SECOND, if_init, NULL);
+SYSINIT(interfaces, SI_SUB_INIT_IF, SI_ORDER_FIRST, if_init, NULL);
#ifdef VIMAGE
@@ -385,16 +390,25 @@ VNET_SYSUNINIT(vnet_if_uninit, SI_SUB_IN
static void
if_grow(void)
{
+ int oldlim;
u_int n;
struct ifindex_entry *e;
- V_if_indexlim <<= 1;
- n = V_if_indexlim * sizeof(*e);
+ IFNET_WLOCK_ASSERT();
+ oldlim = V_if_indexlim;
+ IFNET_WUNLOCK();
+ n = (oldlim << 1) * sizeof(*e);
e = malloc(n, M_IFNET, M_WAITOK | M_ZERO);
+ IFNET_WLOCK();
+ if (V_if_indexlim != oldlim) {
+ free(e, M_IFNET);
+ return;
+ }
if (V_ifindex_table != NULL) {
memcpy((caddr_t)e, (caddr_t)V_ifindex_table, n/2);
free((caddr_t)V_ifindex_table, M_IFNET);
}
+ V_if_indexlim <<= 1;
V_ifindex_table = e;
}
_______________________________________________
[email protected] mailing list
http://lists.freebsd.org/mailman/listinfo/svn-src-all
To unsubscribe, send any mail to "[email protected]"
