| Message ID | 1362997308-5834-1-git-send-email-vfalico@redhat.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
On Mon, Mar 11, 2013 at 11:21:48AM +0100, Veaceslav Falico wrote: > __netpoll_cleanup() is called in netconsole_netdev_event() while holding a > spinlock. Release/acquire the spinlock before/after it and restart the > loop. Also, disable the netconsole completely, because we won't have chance > after the restart of the loop, and might end up in a situation where > nt->enabled == 1 and nt->np.dev == NULL. > > Signed-off-by: Veaceslav Falico <vfalico@redhat.com> > --- > drivers/net/netconsole.c | 15 +++++++++------ > 1 files changed, 9 insertions(+), 6 deletions(-) > > diff --git a/drivers/net/netconsole.c b/drivers/net/netconsole.c > index 37add21..59ac143 100644 > --- a/drivers/net/netconsole.c > +++ b/drivers/net/netconsole.c > @@ -666,6 +666,7 @@ static int netconsole_netdev_event(struct notifier_block *this, > goto done; > > spin_lock_irqsave(&target_list_lock, flags); > +restart: > list_for_each_entry(nt, &target_list, list) { > netconsole_target_get(nt); > if (nt->np.dev == dev) { > @@ -678,15 +679,17 @@ static int netconsole_netdev_event(struct notifier_block *this, > case NETDEV_UNREGISTER: > /* > * rtnl_lock already held > + * we might sleep in __netpoll_cleanup() > */ > - if (nt->np.dev) { > - __netpoll_cleanup(&nt->np); > - dev_put(nt->np.dev); > - nt->np.dev = NULL; > - } > + spin_unlock_irqrestore(&target_list_lock, flags); > + __netpoll_cleanup(&nt->np); > + spin_lock_irqsave(&target_list_lock, flags); > + dev_put(nt->np.dev); > + nt->np.dev = NULL; > nt->enabled = 0; > stopped = true; > - break; > + netconsole_target_put(nt); > + goto restart; > } > } > netconsole_target_put(nt); > -- > 1.7.1 > > Acked-by: Neil Horman <nhorman@tuxdriver.com> -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: Neil Horman <nhorman@tuxdriver.com> Date: Mon, 11 Mar 2013 07:38:56 -0400 > On Mon, Mar 11, 2013 at 11:21:48AM +0100, Veaceslav Falico wrote: >> __netpoll_cleanup() is called in netconsole_netdev_event() while holding a >> spinlock. Release/acquire the spinlock before/after it and restart the >> loop. Also, disable the netconsole completely, because we won't have chance >> after the restart of the loop, and might end up in a situation where >> nt->enabled == 1 and nt->np.dev == NULL. >> >> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> ... > Acked-by: Neil Horman <nhorman@tuxdriver.com> Applied. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/net/netconsole.c b/drivers/net/netconsole.c index 37add21..59ac143 100644 --- a/drivers/net/netconsole.c +++ b/drivers/net/netconsole.c @@ -666,6 +666,7 @@ static int netconsole_netdev_event(struct notifier_block *this, goto done; spin_lock_irqsave(&target_list_lock, flags); +restart: list_for_each_entry(nt, &target_list, list) { netconsole_target_get(nt); if (nt->np.dev == dev) { @@ -678,15 +679,17 @@ static int netconsole_netdev_event(struct notifier_block *this, case NETDEV_UNREGISTER: /* * rtnl_lock already held + * we might sleep in __netpoll_cleanup() */ - if (nt->np.dev) { - __netpoll_cleanup(&nt->np); - dev_put(nt->np.dev); - nt->np.dev = NULL; - } + spin_unlock_irqrestore(&target_list_lock, flags); + __netpoll_cleanup(&nt->np); + spin_lock_irqsave(&target_list_lock, flags); + dev_put(nt->np.dev); + nt->np.dev = NULL; nt->enabled = 0; stopped = true; - break; + netconsole_target_put(nt); + goto restart; } } netconsole_target_put(nt);
__netpoll_cleanup() is called in netconsole_netdev_event() while holding a spinlock. Release/acquire the spinlock before/after it and restart the loop. Also, disable the netconsole completely, because we won't have chance after the restart of the loop, and might end up in a situation where nt->enabled == 1 and nt->np.dev == NULL. Signed-off-by: Veaceslav Falico <vfalico@redhat.com> --- drivers/net/netconsole.c | 15 +++++++++------ 1 files changed, 9 insertions(+), 6 deletions(-)