From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andy Gospodarek Subject: Re: [Bugme-new] [Bug 9543] New: RTNL: assertion failed at net/ipv6/addrconf.c (2164)/RTNL: assertion failed at net/ipv4/devinet.c (1055) Date: Fri, 14 Dec 2007 13:26:38 -0500 Message-ID: <20071214182638.GC25879@gospo.usersys.redhat.com> References: <28503.1197481615@death> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Jay Vosburgh , Herbert Xu , Andrew Morton , bugme-daemon@bugzilla.kernel.org, shemminger@linux-foundation.org, davem@davemloft.net, netdev@vger.kernel.org, andy@greyhouse.net To: Krzysztof Oledzki Return-path: Received: from mx1.redhat.com ([66.187.233.31]:33489 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751283AbXLNS11 (ORCPT ); Fri, 14 Dec 2007 13:27:27 -0500 Content-Disposition: inline In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On Fri, Dec 14, 2007 at 05:14:57PM +0100, Krzysztof Oledzki wrote: > > > On Wed, 12 Dec 2007, Jay Vosburgh wrote: > > >Herbert Xu wrote: > > > >>>diff -puN drivers/net/bonding/bond_sysfs.c~bonding-locking-fix > >>>drivers/net/bonding/bond_sysfs.c > >>>--- a/drivers/net/bonding/bond_sysfs.c~bonding-locking-fix > >>>+++ a/drivers/net/bonding/bond_sysfs.c > >>>@@ -1111,8 +1111,6 @@ static ssize_t bonding_store_primary(str > >>>out: > >>> write_unlock_bh(&bond->lock); > >>> > >>>- rtnl_unlock(); > >>>- > >> > >>Looking at the changeset that added this perhaps the intention > >>is to hold the lock? If so we should add an rtnl_lock to the start > >>of the function. > > > > Yes, this function needs to hold locks, and more than just > >what's there now. I believe the following should be correct; I haven't > >tested it, though (I'm supposedly on vacation right now). > > > > The following change should be correct for the > >bonding_store_primary case discussed in this thread, and also corrects > >the bonding_store_active case which performs similar functions. > > > > The bond_change_active_slave and bond_select_active_slave > >functions both require rtnl, bond->lock for read and curr_slave_lock for > >write_bh, and no other locks. This is so that the lower level > >mode-specific functions can release locks down to just rtnl in order to > >call, e.g., dev_set_mac_address with the locks it expects (rtnl only). > > > >Signed-off-by: Jay Vosburgh > > > >diff --git a/drivers/net/bonding/bond_sysfs.c > >b/drivers/net/bonding/bond_sysfs.c > >index 11b76b3..28a2d80 100644 > >--- a/drivers/net/bonding/bond_sysfs.c > >+++ b/drivers/net/bonding/bond_sysfs.c > >@@ -1075,7 +1075,10 @@ static ssize_t bonding_store_primary(struct device > >*d, > > struct slave *slave; > > struct bonding *bond = to_bond(d); > > > >- write_lock_bh(&bond->lock); > >+ rtnl_lock(); > >+ read_lock(&bond->lock); > >+ write_lock_bh(&bond->curr_slave_lock); > >+ > > if (!USES_PRIMARY(bond->params.mode)) { > > printk(KERN_INFO DRV_NAME > > ": %s: Unable to set primary slave; %s is in mode > > %d\n", > >@@ -1109,8 +1112,8 @@ static ssize_t bonding_store_primary(struct device > >*d, > > } > > } > >out: > >- write_unlock_bh(&bond->lock); > >- > >+ write_unlock_bh(&bond->curr_slave_lock); > >+ read_unlock(&bond->lock); > > rtnl_unlock(); > > > > return count; > >@@ -1190,7 +1193,8 @@ static ssize_t bonding_store_active_slave(struct > >device *d, > > struct bonding *bond = to_bond(d); > > > > rtnl_lock(); > >- write_lock_bh(&bond->lock); > >+ read_lock(&bond->lock); > >+ write_lock_bh(&bond->curr_slave_lock); > > > > if (!USES_PRIMARY(bond->params.mode)) { > > printk(KERN_INFO DRV_NAME > >@@ -1247,7 +1251,8 @@ static ssize_t bonding_store_active_slave(struct > >device *d, > > } > > } > >out: > >- write_unlock_bh(&bond->lock); > >+ write_unlock_bh(&bond->curr_slave_lock); > >+ read_unlock(&bond->lock); > > rtnl_unlock(); > > > > return count; > > Vanilla 2.6.24-rc5 plus this patch: > > ========================================================= > [ INFO: possible irq lock inversion dependency detected ] > 2.6.24-rc5 #1 > --------------------------------------------------------- > events/0/9 just changed the state of lock: > (&mc->mca_lock){-+..}, at: [] mld_ifc_timer_expire+0x130/0x1fb > but this lock took another, soft-read-irq-unsafe lock in the past: > (&bond->lock){-.--} > > and interrupts could create inverse lock ordering between them. > > Grrr, I should have seen that -- sorry. Try your luck with this instead: diff --git a/drivers/net/bonding/bond_sysfs.c b/drivers/net/bonding/bond_sysfs.c index 11b76b3..0694254 100644 --- a/drivers/net/bonding/bond_sysfs.c +++ b/drivers/net/bonding/bond_sysfs.c @@ -1075,7 +1075,10 @@ static ssize_t bonding_store_primary(struct device *d, struct slave *slave; struct bonding *bond = to_bond(d); - write_lock_bh(&bond->lock); + rtnl_lock(); + read_lock_bh(&bond->lock); + write_lock_bh(&bond->curr_slave_lock); + if (!USES_PRIMARY(bond->params.mode)) { printk(KERN_INFO DRV_NAME ": %s: Unable to set primary slave; %s is in mode %d\n", @@ -1109,8 +1112,8 @@ static ssize_t bonding_store_primary(struct device *d, } } out: - write_unlock_bh(&bond->lock); - + write_unlock_bh(&bond->curr_slave_lock); + read_unlock_bh(&bond->lock); rtnl_unlock(); return count; @@ -1190,7 +1193,8 @@ static ssize_t bonding_store_active_slave(struct device *d, struct bonding *bond = to_bond(d); rtnl_lock(); - write_lock_bh(&bond->lock); + read_lock_bh(&bond->lock); + write_lock_bh(&bond->curr_slave_lock); if (!USES_PRIMARY(bond->params.mode)) { printk(KERN_INFO DRV_NAME @@ -1247,7 +1251,8 @@ static ssize_t bonding_store_active_slave(struct device *d, } } out: - write_unlock_bh(&bond->lock); + write_unlock_bh(&bond->curr_slave_lock); + read_unlock_bh(&bond->lock); rtnl_unlock(); return count;